| <!DOCTYPE HTML> |
| <!-- NewPage --> |
| <html lang="en"> |
| <head> |
| <!-- Generated by javadoc (11.0.18) on Wed Mar 01 02:01:42 GMT 2023 --> |
| <title>ITwoPhaseStatefulComponent (Heron Java API)</title> |
| <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> |
| <meta name="dc.created" content="2023-03-01"> |
| <link rel="stylesheet" type="text/css" href="../../../../../stylesheet.css" title="Style"> |
| <link rel="stylesheet" type="text/css" href="../../../../../jquery/jquery-ui.min.css" title="Style"> |
| <link rel="stylesheet" type="text/css" href="../../../../../jquery-ui.overrides.css" title="Style"> |
| <script type="text/javascript" src="../../../../../script.js"></script> |
| <script type="text/javascript" src="../../../../../jquery/jszip/dist/jszip.min.js"></script> |
| <script type="text/javascript" src="../../../../../jquery/jszip-utils/dist/jszip-utils.min.js"></script> |
| <!--[if IE]> |
| <script type="text/javascript" src="../../../../../jquery/jszip-utils/dist/jszip-utils-ie.min.js"></script> |
| <![endif]--> |
| <script type="text/javascript" src="../../../../../jquery/jquery-3.6.0.min.js"></script> |
| <script type="text/javascript" src="../../../../../jquery/jquery-ui.min.js"></script> |
| </head> |
| <body> |
| <script type="text/javascript"><!-- |
| try { |
| if (location.href.indexOf('is-external=true') == -1) { |
| parent.document.title="ITwoPhaseStatefulComponent (Heron Java API)"; |
| } |
| } |
| catch(err) { |
| } |
| //--> |
| var data = {"i0":6,"i1":6}; |
| var tabs = {65535:["t0","All Methods"],2:["t2","Instance Methods"],4:["t3","Abstract Methods"]}; |
| var altColor = "altColor"; |
| var rowColor = "rowColor"; |
| var tableTab = "tableTab"; |
| var activeTableTab = "activeTableTab"; |
| var pathtoroot = "../../../../../"; |
| var useModuleDirectories = true; |
| loadScripts(document, 'script');</script> |
| <noscript> |
| <div>JavaScript is disabled on your browser.</div> |
| </noscript> |
| <header role="banner"> |
| <nav role="navigation"> |
| <div class="fixedNav"> |
| <!-- ========= START OF TOP NAVBAR ======= --> |
| <div class="topNav"><a id="navbar.top"> |
| <!-- --> |
| </a> |
| <div class="skipNav"><a href="#skip.navbar.top" title="Skip navigation links">Skip navigation links</a></div> |
| <a id="navbar.top.firstrow"> |
| <!-- --> |
| </a> |
| <ul class="navList" title="Navigation"> |
| <li><a href="../../../../../index.html">Overview</a></li> |
| <li><a href="package-summary.html">Package</a></li> |
| <li class="navBarCell1Rev">Class</li> |
| <li><a href="package-tree.html">Tree</a></li> |
| <li><a href="../../../../../deprecated-list.html">Deprecated</a></li> |
| <li><a href="../../../../../index-all.html">Index</a></li> |
| <li><a href="../../../../../help-doc.html">Help</a></li> |
| </ul> |
| </div> |
| <div class="subNav"> |
| <ul class="navList" id="allclasses_navbar_top"> |
| <li><a href="../../../../../allclasses.html">All Classes</a></li> |
| </ul> |
| <ul class="navListSearch"> |
| <li><label for="search">SEARCH:</label> |
| <input type="text" id="search" value="search" disabled="disabled"> |
| <input type="reset" id="reset" value="reset" disabled="disabled"> |
| </li> |
| </ul> |
| <div> |
| <script type="text/javascript"><!-- |
| allClassesLink = document.getElementById("allclasses_navbar_top"); |
| if(window==top) { |
| allClassesLink.style.display = "block"; |
| } |
| else { |
| allClassesLink.style.display = "none"; |
| } |
| //--> |
| </script> |
| <noscript> |
| <div>JavaScript is disabled on your browser.</div> |
| </noscript> |
| </div> |
| <div> |
| <ul class="subNavList"> |
| <li>Summary: </li> |
| <li>Nested | </li> |
| <li>Field | </li> |
| <li>Constr | </li> |
| <li><a href="#method.summary">Method</a></li> |
| </ul> |
| <ul class="subNavList"> |
| <li>Detail: </li> |
| <li>Field | </li> |
| <li>Constr | </li> |
| <li><a href="#method.detail">Method</a></li> |
| </ul> |
| </div> |
| <a id="skip.navbar.top"> |
| <!-- --> |
| </a></div> |
| <!-- ========= END OF TOP NAVBAR ========= --> |
| </div> |
| <div class="navPadding"> </div> |
| <script type="text/javascript"><!-- |
| $('.navPadding').css('padding-top', $('.fixedNav').css("height")); |
| //--> |
| </script> |
| </nav> |
| </header> |
| <!-- ======== START OF CLASS DATA ======== --> |
| <main role="main"> |
| <div class="header"> |
| <div class="subTitle"><span class="packageLabelInType">Package</span> <a href="package-summary.html">org.apache.heron.api.topology</a></div> |
| <h2 title="Interface ITwoPhaseStatefulComponent" class="title">Interface ITwoPhaseStatefulComponent<K extends java.io.Serializable,​V extends java.io.Serializable></h2> |
| </div> |
| <div class="contentContainer"> |
| <div class="description"> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <dl> |
| <dt>All Superinterfaces:</dt> |
| <dd><code><a href="IComponent.html" title="interface in org.apache.heron.api.topology">IComponent</a></code>, <code><a href="IStatefulComponent.html" title="interface in org.apache.heron.api.topology">IStatefulComponent</a><K,​V></code>, <code>java.io.Serializable</code></dd> |
| </dl> |
| <dl> |
| <dt>All Known Implementing Classes:</dt> |
| <dd><code><a href="../../resource/TestTwoPhaseStatefulBolt.html" title="class in org.apache.heron.resource">TestTwoPhaseStatefulBolt</a></code>, <code><a href="../../resource/TestTwoPhaseStatefulSpout.html" title="class in org.apache.heron.resource">TestTwoPhaseStatefulSpout</a></code></dd> |
| </dl> |
| <hr> |
| <pre>public interface <span class="typeNameLabel">ITwoPhaseStatefulComponent<K extends java.io.Serializable,​V extends java.io.Serializable></span> |
| extends <a href="IStatefulComponent.html" title="interface in org.apache.heron.api.topology">IStatefulComponent</a><K,​V></pre> |
| <div class="block">Defines a stateful component that is aware of Heron topology's "two-phase commit". |
| |
| Note tasks saving a distributed checkpoint would be the "prepare" phase of the two-phase commit |
| algorithm. When a distributed checkpoint is done, we can say that all tasks agree that they |
| will not roll back to the time before that distributed checkpoint, and the "prepare" phase is |
| complete. |
| |
| When the "prepare" phase is complete, Heron will invoke the "postSave" hook to signal the |
| beginning of the "commit" phase. If there is a failure occurred during the "prepare" phase, |
| Heron will invoke the hook "preRestore" to signal that two-phase commit is aborted, and the |
| topology will be rolled back to the previous checkpoint. |
| |
| Note that the commit phase will finish after the postSave hook exits successfully. Then, the |
| prepare phase of the following checkpoint will begin. |
| |
| In addition, for two-phase stateful components specifically, Heron will not execute (for bolts) |
| or produce (for spouts) tuples between preSave and postSave. This will guarantee that the prepare |
| phase of the next checkpoint will not overlap with the commit phase of the current checkpoint |
| (eg. we block execution of tuples from the next checkpoint unless commit phase is done). |
| |
| See the end-to-end effectively-once designed doc (linked in the PR of this commit) for more |
| details.</div> |
| </li> |
| </ul> |
| </div> |
| <div class="summary"> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <!-- ========== METHOD SUMMARY =========== --> |
| <section> |
| <ul class="blockList"> |
| <li class="blockList"><a id="method.summary"> |
| <!-- --> |
| </a> |
| <h3>Method Summary</h3> |
| <table class="memberSummary"> |
| <caption><span id="t0" class="activeTableTab"><span>All Methods</span><span class="tabEnd"> </span></span><span id="t2" class="tableTab"><span><a href="javascript:show(2);">Instance Methods</a></span><span class="tabEnd"> </span></span><span id="t3" class="tableTab"><span><a href="javascript:show(4);">Abstract Methods</a></span><span class="tabEnd"> </span></span></caption> |
| <tr> |
| <th class="colFirst" scope="col">Modifier and Type</th> |
| <th class="colSecond" scope="col">Method</th> |
| <th class="colLast" scope="col">Description</th> |
| </tr> |
| <tr id="i0" class="altColor"> |
| <td class="colFirst"><code>void</code></td> |
| <th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#postSave(java.lang.String)">postSave</a></span>​(java.lang.String checkpointId)</code></th> |
| <td class="colLast"> |
| <div class="block">This is a hook for the component to perform some actions after a checkpoint is persisted |
| successfully for all components in the topology.</div> |
| </td> |
| </tr> |
| <tr id="i1" class="rowColor"> |
| <td class="colFirst"><code>void</code></td> |
| <th class="colSecond" scope="row"><code><span class="memberNameLink"><a href="#preRestore(java.lang.String)">preRestore</a></span>​(java.lang.String checkpointId)</code></th> |
| <td class="colLast"> |
| <div class="block">This is a hook for the component to perform some actions (eg.</div> |
| </td> |
| </tr> |
| </table> |
| <ul class="blockList"> |
| <li class="blockList"><a id="methods.inherited.from.class.org.apache.heron.api.topology.IComponent"> |
| <!-- --> |
| </a> |
| <h3>Methods inherited from interface org.apache.heron.api.topology.<a href="IComponent.html" title="interface in org.apache.heron.api.topology">IComponent</a></h3> |
| <code><a href="IComponent.html#declareOutputFields(org.apache.heron.api.topology.OutputFieldsDeclarer)">declareOutputFields</a>, <a href="IComponent.html#getComponentConfiguration()">getComponentConfiguration</a></code></li> |
| </ul> |
| <ul class="blockList"> |
| <li class="blockList"><a id="methods.inherited.from.class.org.apache.heron.api.topology.IStatefulComponent"> |
| <!-- --> |
| </a> |
| <h3>Methods inherited from interface org.apache.heron.api.topology.<a href="IStatefulComponent.html" title="interface in org.apache.heron.api.topology">IStatefulComponent</a></h3> |
| <code><a href="IStatefulComponent.html#initState(org.apache.heron.api.state.State)">initState</a>, <a href="IStatefulComponent.html#preSave(java.lang.String)">preSave</a></code></li> |
| </ul> |
| </li> |
| </ul> |
| </section> |
| </li> |
| </ul> |
| </div> |
| <div class="details"> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <!-- ============ METHOD DETAIL ========== --> |
| <section> |
| <ul class="blockList"> |
| <li class="blockList"><a id="method.detail"> |
| <!-- --> |
| </a> |
| <h3>Method Detail</h3> |
| <a id="postSave(java.lang.String)"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>postSave</h4> |
| <pre class="methodSignature">void postSave​(java.lang.String checkpointId)</pre> |
| <div class="block">This is a hook for the component to perform some actions after a checkpoint is persisted |
| successfully for all components in the topology.</div> |
| <dl> |
| <dt><span class="paramLabel">Parameters:</span></dt> |
| <dd><code>checkpointId</code> - the ID of the checkpoint</dd> |
| </dl> |
| </li> |
| </ul> |
| <a id="preRestore(java.lang.String)"> |
| <!-- --> |
| </a> |
| <ul class="blockListLast"> |
| <li class="blockList"> |
| <h4>preRestore</h4> |
| <pre class="methodSignature">void preRestore​(java.lang.String checkpointId)</pre> |
| <div class="block">This is a hook for the component to perform some actions (eg. state clean-up) before the |
| framework attempts to delete the component and restore it to a previously-saved checkpoint.</div> |
| <dl> |
| <dt><span class="paramLabel">Parameters:</span></dt> |
| <dd><code>checkpointId</code> - the ID of the checkpoint that the component is being restored to</dd> |
| </dl> |
| </li> |
| </ul> |
| </li> |
| </ul> |
| </section> |
| </li> |
| </ul> |
| </div> |
| </div> |
| </main> |
| <!-- ========= END OF CLASS DATA ========= --> |
| <footer role="contentinfo"> |
| <nav role="navigation"> |
| <!-- ======= START OF BOTTOM NAVBAR ====== --> |
| <div class="bottomNav"><a id="navbar.bottom"> |
| <!-- --> |
| </a> |
| <div class="skipNav"><a href="#skip.navbar.bottom" title="Skip navigation links">Skip navigation links</a></div> |
| <a id="navbar.bottom.firstrow"> |
| <!-- --> |
| </a> |
| <ul class="navList" title="Navigation"> |
| <li><a href="../../../../../index.html">Overview</a></li> |
| <li><a href="package-summary.html">Package</a></li> |
| <li class="navBarCell1Rev">Class</li> |
| <li><a href="package-tree.html">Tree</a></li> |
| <li><a href="../../../../../deprecated-list.html">Deprecated</a></li> |
| <li><a href="../../../../../index-all.html">Index</a></li> |
| <li><a href="../../../../../help-doc.html">Help</a></li> |
| </ul> |
| </div> |
| <div class="subNav"> |
| <ul class="navList" id="allclasses_navbar_bottom"> |
| <li><a href="../../../../../allclasses.html">All Classes</a></li> |
| </ul> |
| <div> |
| <script type="text/javascript"><!-- |
| allClassesLink = document.getElementById("allclasses_navbar_bottom"); |
| if(window==top) { |
| allClassesLink.style.display = "block"; |
| } |
| else { |
| allClassesLink.style.display = "none"; |
| } |
| //--> |
| </script> |
| <noscript> |
| <div>JavaScript is disabled on your browser.</div> |
| </noscript> |
| </div> |
| <div> |
| <ul class="subNavList"> |
| <li>Summary: </li> |
| <li>Nested | </li> |
| <li>Field | </li> |
| <li>Constr | </li> |
| <li><a href="#method.summary">Method</a></li> |
| </ul> |
| <ul class="subNavList"> |
| <li>Detail: </li> |
| <li>Field | </li> |
| <li>Constr | </li> |
| <li><a href="#method.detail">Method</a></li> |
| </ul> |
| </div> |
| <a id="skip.navbar.bottom"> |
| <!-- --> |
| </a></div> |
| <!-- ======== END OF BOTTOM NAVBAR ======= --> |
| </nav> |
| </footer> |
| </body> |
| </html> |
