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menu__list-item--collapsed"><div class=menu__list-item-collapsible><a class="categoryLink_byQd menu__link menu__link--sublist menu__link--sublist-caret" role=button aria-expanded=false href=/zh-CN/docs/row-format/><span title=行格式 class=categoryLinkLabel_W154>行格式</span></a></div><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class=menu__list-item-collapsible><a class="categoryLink_byQd menu__link menu__link--sublist menu__link--sublist-caret" role=button aria-expanded=false href=/zh-CN/docs/json/><span title="Fory JSON" class=categoryLinkLabel_W154>Fory JSON</span></a></div><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class=menu__list-item-collapsible><a class="categoryLink_byQd menu__link menu__link--sublist menu__link--sublist-caret" role=button aria-expanded=false href=/zh-CN/docs/compiler/><span title="Fory IDL 与编译器" class=categoryLinkLabel_W154>Fory IDL 与编译器</span></a></div><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class=menu__list-item-collapsible><a class="categoryLink_byQd menu__link menu__link--sublist menu__link--sublist-caret" role=button aria-expanded=false href=/zh-CN/docs/grpc/><span title="Fory gRPC" class=categoryLinkLabel_W154>Fory gRPC</span></a></div><li class="theme-doc-sidebar-item-category theme-doc-sidebar-item-category-level-1 menu__list-item menu__list-item--collapsed"><div class=menu__list-item-collapsible><a class="categoryLink_byQd menu__link menu__link--sublist menu__link--sublist-caret" role=button aria-expanded=false href=/zh-CN/docs/development/><span title=开发 class=categoryLinkLabel_W154>开发</span></a></div></ul></nav></div></div></aside><main class=docMainContainer_TBSr><div class="container padding-top--md padding-bottom--lg"><div class=row><div class="col docItemCol_VOVn"><div class=docItemContainer_Djhp><article><nav class="theme-doc-breadcrumbs breadcrumbsContainer_Z_bl" aria-label=页面路径><ul class=breadcrumbs><li class=breadcrumbs__item><a aria-label=主页面 class=breadcrumbs__link href=/zh-CN/><svg viewBox="0 0 24 24" class=breadcrumbHomeIcon_YNFT><path d="M10 19v-5h4v5c0 .55.45 1 1 1h3c.55 0 1-.45 1-1v-7h1.7c.46 0 .68-.57.33-.87L12.67 3.6c-.38-.34-.96-.34-1.34 0l-8.36 7.53c-.34.3-.13.87.33.87H5v7c0 .55.45 1 1 1h3c.55 0 1-.45 1-1z" fill=currentColor /></svg></a><li class=breadcrumbs__item><span class=breadcrumbs__link>对象序列化</span><li class=breadcrumbs__item><a class=breadcrumbs__link href=/zh-CN/docs/object-serialization/cpp/><span>C++</span></a><li class="breadcrumbs__item breadcrumbs__item--active"><span class=breadcrumbs__link>Schema 演进</span></ul></nav><span class="theme-doc-version-badge badge badge--secondary">版本：1.6.0</span><div class="tocCollapsible_ETCw theme-doc-toc-mobile tocMobile_ITEo"><button type=button class="clean-btn tocCollapsibleButton_TO0P">本页总览</button></div><div class="theme-doc-markdown markdown"><header><h1>Schema 演进</h1></header><p>Apache Fory™ 在<strong>兼容模式</strong>中支持 Schema 演进，允许序列化和反序列化对等端使用不同的类型定义。</p> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=兼容模式>兼容模式<a href=#兼容模式 class=hash-link aria-label=兼容模式的直接链接 title=兼容模式的直接链接 translate=no></a></h2> |
| <p>兼容模式默认启用：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token macro property directive-hash" style=color:#36acaa>#</span><span class="token macro property directive keyword" style=color:#00009f>include</span><span class="token macro property" style=color:#36acaa> </span><span class="token macro property string" style=color:#e3116c>"fory/serialization/fory.h"</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>using</span><span class="token plain"> </span><span class="token keyword" style=color:#00009f>namespace</span><span class="token plain"> fory</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">serialization</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Version 1: Original schema</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">PersonV1</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string name</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>int32_t</span><span class="token plain"> age</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">PersonV1</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> name</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> age</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Version 2: Added email field</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">PersonV2</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string name</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>int32_t</span><span class="token plain"> age</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string email</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// NEW FIELD</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">PersonV2</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> name</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> age</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> email</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>int</span><span class="token plain"> </span><span class="token function" style=color:#d73a49>main</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Create separate Fory instances for each schema version</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> fory_v1 </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> </span><span class="token class-name">Fory</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token function" style=color:#d73a49>builder</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>xlang</span><span class="token punctuation" style=color:#393A34>(</span><span class="token boolean" style=color:#36acaa>true</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>build</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> fory_v2 </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> </span><span class="token class-name">Fory</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token function" style=color:#d73a49>builder</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>xlang</span><span class="token punctuation" style=color:#393A34>(</span><span class="token boolean" style=color:#36acaa>true</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>build</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Register with the SAME type ID for schema evolution</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>constexpr</span><span class="token plain"> </span><span class="token keyword" style=color:#00009f>uint32_t</span><span class="token plain"> PERSON_TYPE_ID </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>100</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> fory_v1</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>register_struct</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">PersonV1</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">PERSON_TYPE_ID</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> fory_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>register_struct</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">PersonV2</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">PERSON_TYPE_ID</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Serialize with V1</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> PersonV1 v1</span><span class="token punctuation" style=color:#393A34>{</span><span class="token string" style=color:#e3116c>"Alice"</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>30</span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> bytes </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_v1</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>serialize</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v1</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Deserialize as V2 - email gets default value (empty string)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> v2 </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>deserialize</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">PersonV2</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">bytes</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">name </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"Alice"</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">age </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>30</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">email </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>""</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Default value for missing field</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>return</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>0</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><br/></div></code></pre></div></div> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=schema-演进功能>Schema 演进功能<a href=#schema-演进功能 class=hash-link aria-label="Schema 演进功能的直接链接" title="Schema 演进功能的直接链接" translate=no></a></h2> |
| <p>兼容模式支持以下 Schema 变更：</p> |
| <table><thead><tr><th>变更类型<th>支持情况<th>行为<tbody><tr><td>添加新字段<td>支持<td>缺失字段使用默认值<tr><td>删除字段<td>支持<td>跳过多余字段<tr><td>重排字段<td>支持<td>按名称而非位置匹配字段<tr><td>更改可空性<td>支持<td><code>T</code> ↔ <code>std::optional<T></code><tr><td>更改字段类型<td>部分支持<td>标量变更必须无损<tr><td>重命名字段<td>不支持<td>字段名称必须匹配（区分大小写）</table> |
| <p>当值可以无损转换时，兼容读取端可以处理部分标量字段类型变更。如果转换后的值具有相同逻辑值，匹配字段可以在 <code>bool</code>、<code>std::string</code>、数字标量和十进制字段之间读取。布尔字符串必须严格为 <code>"0"</code>、<code>"1"</code>、<code>"true"</code> 或 <code>"false"</code>。数字字符串必须使用有限的 ASCII 十进制表示，不允许空白、前导 <code>+</code>、Unicode 数字、分隔符或 <code>NaN</code> 和 <code>Infinity</code> 等非有限值。数字和十进制可以读取为规范字符串；只有不丢失精度或范围时，数字扩宽或缩窄才会成功。可空和可选字段包装器仍可与这些转换组合，但启用引用跟踪的标量类型变更不兼容。无效字符串和有损转换会在反序列化期间失败。</p> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=添加字段向后兼容>添加字段（向后兼容）<a href=#添加字段向后兼容 class=hash-link aria-label=添加字段（向后兼容）的直接链接 title=添加字段（向后兼容）的直接链接 translate=no></a></h2> |
| <p>使用包含新增字段的新 Schema 反序列化旧数据时：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// Old schema (V1)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">ProductV1</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string name</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>double</span><span class="token plain"> price</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">ProductV1</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> name</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> price</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// New schema (V2) with additional fields</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">ProductV2</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string name</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>double</span><span class="token plain"> price</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">vector</span><span class="token operator" style=color:#393A34><</span><span class="token plain">std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string</span><span class="token operator" style=color:#393A34>></span><span class="token plain"> tags</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// NEW</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">map</span><span class="token operator" style=color:#393A34><</span><span class="token plain">std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string</span><span class="token operator" style=color:#393A34>></span><span class="token plain"> attributes</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// NEW</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">ProductV2</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> name</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> price</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> tags</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> attributes</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Serialize V1</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">ProductV1 v1</span><span class="token punctuation" style=color:#393A34>{</span><span class="token string" style=color:#e3116c>"Laptop"</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>999.99</span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> bytes </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_v1</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>serialize</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v1</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Deserialize as V2</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> v2 </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>deserialize</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">ProductV2</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">bytes</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">name </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"Laptop"</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">price </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>999.99</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">tags</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>empty</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Default: empty vector</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">attributes</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>empty</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Default: empty map</span><br/></div></code></pre></div></div> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=删除字段向前兼容>删除字段（向前兼容）<a href=#删除字段向前兼容 class=hash-link aria-label=删除字段（向前兼容）的直接链接 title=删除字段（向前兼容）的直接链接 translate=no></a></h2> |
| <p>使用字段较少的旧 Schema 反序列化新数据时：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// Full schema</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">UserFull</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>int64_t</span><span class="token plain"> id</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string username</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string email</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string password_hash</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>int32_t</span><span class="token plain"> login_count</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">UserFull</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> id</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> username</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> email</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> password_hash</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> login_count</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Minimal schema (removed 3 fields)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">UserMinimal</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>int64_t</span><span class="token plain"> id</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string username</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">UserMinimal</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> id</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> username</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Serialize full version</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">UserFull full</span><span class="token punctuation" style=color:#393A34>{</span><span class="token number" style=color:#36acaa>12345</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"johndoe"</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"john@example.com"</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"hash123"</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>42</span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> bytes </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_full</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>serialize</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">full</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Deserialize as minimal - extra fields are skipped</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> minimal </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_minimal</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>deserialize</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">UserMinimal</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">bytes</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">minimal</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">id </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>12345</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">minimal</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">username </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"johndoe"</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// email, password_hash, login_count are skipped</span><br/></div></code></pre></div></div> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=字段重排>字段重排<a href=#字段重排 class=hash-link aria-label=字段重排的直接链接 title=字段重排的直接链接 translate=no></a></h2> |
| <p>在兼容模式中，字段按名称而非位置匹配：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// Original field order</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">ConfigOriginal</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string host</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>int32_t</span><span class="token plain"> port</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>bool</span><span class="token plain"> enable_ssl</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string protocol</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">ConfigOriginal</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> host</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> port</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> enable_ssl</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> protocol</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Reordered fields</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">ConfigReordered</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>bool</span><span class="token plain"> enable_ssl</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Moved to first</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string protocol</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Moved to second</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string host</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Moved to third</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>int32_t</span><span class="token plain"> port</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Moved to last</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">ConfigReordered</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> enable_ssl</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> protocol</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> host</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> port</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Serialize with original order</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">ConfigOriginal orig</span><span class="token punctuation" style=color:#393A34>{</span><span class="token string" style=color:#e3116c>"localhost"</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>8080</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token boolean" style=color:#36acaa>true</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"https"</span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> bytes </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_orig</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>serialize</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">orig</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Deserialize with different field order - works correctly</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> reordered </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_reord</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>deserialize</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">ConfigReordered</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">bytes</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">reordered</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">host </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"localhost"</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">reordered</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">port </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>8080</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">reordered</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">enable_ssl </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token boolean" style=color:#36acaa>true</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">reordered</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">protocol </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"https"</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><br/></div></code></pre></div></div> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=嵌套结构体演进>嵌套结构体演进<a href=#嵌套结构体演进 class=hash-link aria-label=嵌套结构体演进的直接链接 title=嵌套结构体演进的直接链接 translate=no></a></h2> |
| <p>Schema 演进会递归应用于嵌套结构体：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// V1 Address</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">AddressV1</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string street</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string city</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">AddressV1</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> street</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> city</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// V2 Address with new fields</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">AddressV2</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string street</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string city</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string country</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// NEW</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string zipcode</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// NEW</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">AddressV2</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> street</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> city</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> country</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> zipcode</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// V1 Employee with V1 Address</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">EmployeeV1</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string name</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> AddressV1 home_address</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">EmployeeV1</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> name</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> home_address</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// V2 Employee with V2 Address and new field</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">EmployeeV2</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string name</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> AddressV2 home_address</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Nested struct evolved</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string employee_id</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// NEW</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">EmployeeV2</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> name</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> home_address</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> employee_id</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Register types with same IDs</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>constexpr</span><span class="token plain"> </span><span class="token keyword" style=color:#00009f>uint32_t</span><span class="token plain"> ADDRESS_TYPE_ID </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>100</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>constexpr</span><span class="token plain"> </span><span class="token keyword" style=color:#00009f>uint32_t</span><span class="token plain"> EMPLOYEE_TYPE_ID </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>101</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">fory_v1</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>register_struct</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">AddressV1</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">ADDRESS_TYPE_ID</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">fory_v1</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>register_struct</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">EmployeeV1</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">EMPLOYEE_TYPE_ID</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">fory_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>register_struct</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">AddressV2</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">ADDRESS_TYPE_ID</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">fory_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>register_struct</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">EmployeeV2</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">EMPLOYEE_TYPE_ID</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Serialize V1</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">EmployeeV1 emp_v1</span><span class="token punctuation" style=color:#393A34>{</span><span class="token string" style=color:#e3116c>"Jane Doe"</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token string" style=color:#e3116c>"123 Main St"</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"NYC"</span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> bytes </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_v1</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>serialize</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">emp_v1</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Deserialize as V2</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> emp_v2 </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>deserialize</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">EmployeeV2</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">bytes</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">emp_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">name </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"Jane Doe"</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">emp_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">home_address</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">street </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"123 Main St"</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">emp_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">home_address</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">city </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"NYC"</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">emp_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">home_address</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">country </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>""</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Default</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">emp_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">home_address</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">zipcode </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>""</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Default</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">emp_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">employee_id </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>""</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Default</span><br/></div></code></pre></div></div> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=双向演进>双向演进<a href=#双向演进 class=hash-link aria-label=双向演进的直接链接 title=双向演进的直接链接 translate=no></a></h2> |
| <p>Schema 演进可双向工作：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// V2 -> V1 (downgrade)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">PersonV2 v2</span><span class="token punctuation" style=color:#393A34>{</span><span class="token string" style=color:#e3116c>"Charlie"</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>35</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"charlie@example.com"</span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> bytes </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>serialize</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v2</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> v1 </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> fory_v1</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>deserialize</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">PersonV1</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">bytes</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>value</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v1</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">name </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token string" style=color:#e3116c>"Charlie"</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>assert</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">v1</span><span class="token punctuation" style=color:#393A34>.</span><span class="token plain">age </span><span class="token operator" style=color:#393A34>==</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>35</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// email field is discarded during deserialization</span><br/></div></code></pre></div></div> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=默认值>默认值<a href=#默认值 class=hash-link aria-label=默认值的直接链接 title=默认值的直接链接 translate=no></a></h2> |
| <p>字段缺失时使用 C++ 默认初始化：</p> |
| <table><thead><tr><th>类型<th>默认值<tbody><tr><td><code>int8_t</code>, <code>int16_t</code>...<td><code>0</code><tr><td><code>float</code>, <code>double</code><td><code>0.0</code><tr><td><code>bool</code><td><code>false</code><tr><td><code>std::string</code><td><code>""</code><tr><td><code>std::vector<T></code><td>空 vector<tr><td><code>std::map<K,V></code><td>空 map<tr><td><code>std::set<T></code><td>空 set<tr><td><code>std::optional<T></code><td><code>std::nullopt</code><tr><td>结构体类型<td>默认构造</table> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=相同-schema-优化>相同 Schema 优化<a href=#相同-schema-优化 class=hash-link aria-label="相同 Schema 优化的直接链接" title="相同 Schema 优化的直接链接" translate=no></a></h2> |
| <p>跨语言模式和原生模式都默认使用兼容模式。只有每个读取端和写入端始终使用相同 Schema，并且希望获得更快序列化和更小体积时，才显式设置 <code>compatible(false)</code>：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// Same-schema optimization</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> fory </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> </span><span class="token class-name">Fory</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token function" style=color:#d73a49>builder</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>xlang</span><span class="token punctuation" style=color:#393A34>(</span><span class="token boolean" style=color:#36acaa>true</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>compatible</span><span class="token punctuation" style=color:#393A34>(</span><span class="token boolean" style=color:#36acaa>false</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>build</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Serialization/deserialization requires identical schemas</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Schema mismatches may cause errors or undefined behavior</span><br/></div></code></pre></div></div> |
| <p><strong>以下情况使用 <code>compatible(false)</code>：</strong></p> |
| <ul> |
| <li class="">每个读取端和写入端始终使用相同 Schema</li> |
| <li class="">希望获得更快序列化和更小体积</li> |
| <li class="">对于跨语言载荷，每种语言都使用同一套已验证 Schema，或使用由 Fory Schema IDL 生成的原生类型</li> |
| </ul> |
| <h3 class="anchor anchorTargetStickyNavbar_Vzrq" id=按结构体选择退出>按结构体选择退出<a href=#按结构体选择退出 class=hash-link aria-label=按结构体选择退出的直接链接 title=按结构体选择退出的直接链接 translate=no></a></h3> |
| <p>对于单个结构体，可以使用 <code>FORY_STRUCT_EVOLVING</code> 并将其放在 <code>FORY_STRUCT</code> 后，以退出演进元数据：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">SameSchemaMessage</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>int32_t</span><span class="token plain"> id</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">SameSchemaMessage</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> id</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token function" style=color:#d73a49>FORY_STRUCT_EVOLVING</span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">SameSchemaMessage</span><span class="token punctuation" style=color:#393A34>,</span><span class="token plain"> </span><span class="token boolean" style=color:#36acaa>false</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><br/></div></code></pre></div></div> |
| <p><strong>以下情况使用兼容模式：</strong></p> |
| <ul> |
| <li class="">Schema 可能独立演进</li> |
| <li class="">需要跨版本兼容性</li> |
| <li class="">不同服务可能使用不同的 Schema 版本</li> |
| </ul> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=类型-id-要求>类型 ID 要求<a href=#类型-id-要求 class=hash-link aria-label="类型 ID 要求的直接链接" title="类型 ID 要求的直接链接" translate=no></a></h2> |
| <p>要使 Schema 演进正常工作：</p> |
| <ol> |
| <li class=""><strong>类型 ID 相同</strong>：同一结构体的不同版本必须使用相同类型 ID</li> |
| <li class=""><strong>ID 一致</strong>：所有 Fory 实例中的类型 ID 必须一致</li> |
| <li class=""><strong>注册所有版本</strong>：每个 Fory 实例注册自己的结构体版本</li> |
| </ol> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token keyword" style=color:#00009f>constexpr</span><span class="token plain"> </span><span class="token keyword" style=color:#00009f>uint32_t</span><span class="token plain"> PERSON_TYPE_ID </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> </span><span class="token number" style=color:#36acaa>100</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Instance 1 uses PersonV1</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">fory_v1</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>register_struct</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">PersonV1</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">PERSON_TYPE_ID</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Instance 2 uses PersonV2</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain">fory_v2</span><span class="token punctuation" style=color:#393A34>.</span><span class="token generic-function function" style=color:#d73a49>register_struct</span><span class="token generic-function generic class-name operator" style=color:#393A34><</span><span class="token generic-function generic class-name">PersonV2</span><span class="token generic-function generic class-name operator" style=color:#393A34>></span><span class="token punctuation" style=color:#393A34>(</span><span class="token plain">PERSON_TYPE_ID</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain" style=display:inline-block></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Same type ID enables schema evolution</span><br/></div></code></pre></div></div> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=最佳实践>最佳实践<a href=#最佳实践 class=hash-link aria-label=最佳实践的直接链接 title=最佳实践的直接链接 translate=no></a></h2> |
| <h3 class="anchor anchorTargetStickyNavbar_Vzrq" id=1-为演进做好规划>1. 为演进做好规划<a href=#1-为演进做好规划 class=hash-link aria-label="1. 为演进做好规划的直接链接" title="1. 为演进做好规划的直接链接" translate=no></a></h3> |
| <p>设计 Schema 时考虑未来变更：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// Good: Use optional for fields that might be removed</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">Config</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string host</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>int32_t</span><span class="token plain"> port</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">optional</span><span class="token operator" style=color:#393A34><</span><span class="token plain">std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string</span><span class="token operator" style=color:#393A34>></span><span class="token plain"> deprecated_field</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Can be removed later</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><br/></div></code></pre></div></div> |
| <h3 class="anchor anchorTargetStickyNavbar_Vzrq" id=2-使用有意义的默认值>2. 使用有意义的默认值<a href=#2-使用有意义的默认值 class=hash-link aria-label="2. 使用有意义的默认值的直接链接" title="2. 使用有意义的默认值的直接链接" translate=no></a></h3> |
| <p>考虑新字段应使用什么合理的默认值：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token keyword" style=color:#00009f>struct</span><span class="token plain"> </span><span class="token class-name">Settings</span><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>{</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>int32_t</span><span class="token plain"> timeout_ms</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Default: 0 (might want a sensible default)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token keyword" style=color:#00009f>bool</span><span class="token plain"> enabled</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Default: false</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> std</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token plain">string mode</span><span class="token punctuation" style=color:#393A34>;</span><span class="token plain"> </span><span class="token comment" style=color:#999988;font-style:italic>// Default: "" (might want "default")</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token punctuation" style=color:#393A34>}</span><span class="token punctuation" style=color:#393A34>;</span><br/></div></code></pre></div></div> |
| <h3 class="anchor anchorTargetStickyNavbar_Vzrq" id=3-记录-schema-版本>3. 记录 Schema 版本<a href=#3-记录-schema-版本 class=hash-link aria-label="3. 记录 Schema 版本的直接链接" title="3. 记录 Schema 版本的直接链接" translate=no></a></h3> |
| <p>跟踪 Schema 变更以便调试：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// V1: Initial schema (2024-01-01)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// V2: Added email field (2024-02-01)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// V3: Added phone, address fields (2024-03-01)</span><br/></div></code></pre></div></div> |
| <h3 class="anchor anchorTargetStickyNavbar_Vzrq" id=4-测试演进路径>4. 测试演进路径<a href=#4-测试演进路径 class=hash-link aria-label="4. 测试演进路径的直接链接" title="4. 测试演进路径的直接链接" translate=no></a></h3> |
| <p>同时测试升级和降级场景：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// Test V1 -> V2</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Test V2 -> V1</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Test V1 -> V3</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token comment" style=color:#999988;font-style:italic>// Test V3 -> V1</span><br/></div></code></pre></div></div> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=跨语言-schema-演进>跨语言 Schema 演进<a href=#跨语言-schema-演进 class=hash-link aria-label="跨语言 Schema 演进的直接链接" title="跨语言 Schema 演进的直接链接" translate=no></a></h2> |
| <p>使用跨语言模式时，Schema 演进可跨语言工作：</p> |
| <div class="language-cpp codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-cpp codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// C++ with compatible mode, the default</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token keyword" style=color:#00009f>auto</span><span class="token plain"> fory </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> </span><span class="token class-name">Fory</span><span class="token double-colon punctuation" style=color:#393A34>::</span><span class="token function" style=color:#d73a49>builder</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>xlang</span><span class="token punctuation" style=color:#393A34>(</span><span class="token boolean" style=color:#36acaa>true</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>build</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><br/></div></code></pre></div></div> |
| <div class="language-java codeBlockContainer_Ckt0 theme-code-block" style=--prism-color:#393A34;--prism-background-color:#f6f8fa><div class=codeBlockContent_QJqH><pre tabindex=0 class="prism-code language-java codeBlock_bY9V thin-scrollbar" style=color:#393A34;background-color:#f6f8fa><code class=codeBlockLines_e6Vv><div class=token-line style=color:#393A34><span class="token comment" style=color:#999988;font-style:italic>// Java with compatible mode, the default</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"></span><span class="token class-name">Fory</span><span class="token plain"> fory </span><span class="token operator" style=color:#393A34>=</span><span class="token plain"> </span><span class="token class-name">Fory</span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>builder</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>withXlang</span><span class="token punctuation" style=color:#393A34>(</span><span class="token boolean" style=color:#36acaa>true</span><span class="token punctuation" style=color:#393A34>)</span><span class="token plain"></span><br/></div><div class=token-line style=color:#393A34><span class="token plain"> </span><span class="token punctuation" style=color:#393A34>.</span><span class="token function" style=color:#d73a49>build</span><span class="token punctuation" style=color:#393A34>(</span><span class="token punctuation" style=color:#393A34>)</span><span class="token punctuation" style=color:#393A34>;</span><br/></div></code></pre></div></div> |
| <p>即使 Schema 版本不同，两个实例仍可交换数据。</p> |
| <h2 class="anchor anchorTargetStickyNavbar_Vzrq" id=相关主题>相关主题<a href=#相关主题 class=hash-link aria-label=相关主题的直接链接 title=相关主题的直接链接 translate=no></a></h2> |
| <ul> |
| <li class=""><a class="" href=/zh-CN/docs/object-serialization/cpp/configuration>配置</a> - 启用兼容模式</li> |
| <li class=""><a class="" href=/zh-CN/docs/object-serialization/cpp/type-registration>类型注册</a> - 类型 ID 管理</li> |
| <li class=""><a class="" href=/zh-CN/docs/object-serialization/cpp/basic-serialization#cross-language-interoperability>跨语言序列化</a> - 跨语言注意事项</li> |
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