org/apache/sis/metadata/sql/MetadataWriter.html - sis-site - Git at Google

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 <div class="header">
 <div class="sub-title"><span class="package-label-in-type">Package</span>&nbsp;<a href="package-summary.html">org.apache.sis.metadata.sql</a></div>
 <h1 title="Class MetadataWriter" class="title">Class MetadataWriter</h1>
 </div>
 <div class="inheritance" title="Inheritance Tree"><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a>
 <div class="inheritance"><a href="MetadataSource.html" title="class in org.apache.sis.metadata.sql">MetadataSource</a>
 <div class="inheritance">MetadataWriter</div>
 </div>
 </div>
 <section class="class-description" id="class-description">
 <dl class="notes">
 <dt>All Implemented Interfaces:</dt>
 <dd><code><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/AutoCloseable.html" title="class or interface in java.lang" class="external-link">AutoCloseable</a></code></dd>
 </dl>
 <hr>
 <div class="type-signature"><span class="modifiers">public class </span><span class="element-name type-name-label">MetadataWriter</span>
 <span class="extends-implements">extends <a href="MetadataSource.html" title="class in org.apache.sis.metadata.sql">MetadataSource</a></span></div>
 <div class="block">A connection to a metadata database with write capabilities. The database must have a schema of the given name,
  which can be initially empty. Tables and columns are created as needed when the <a href="#add(java.lang.Object)"><code>add(Object)</code></a> method is
  invoked.

  <p>No more than one instance of <code>MetadataWriter</code> should be used for the same database.
  However, multiple instances of <code>MetadataSource</code> can be used concurrently with a single
  <code>MetadataWriter</code> instance on the same database.</p>

  <h2>Properties</h2>
  The constructor expects three Java arguments (the <a href="../MetadataStandard.html" title="class in org.apache.sis.metadata">metadata standard</a>,
  the <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.sql/javax/sql/DataSource.html" title="class or interface in javax.sql" class="external-link">data source</a> and the database schema) completed by an arbitrary amount
  of optional arguments given as a map of properties.
  The following keys are recognized by <code>MetadataSource</code> and all other entries are ignored:

  <table class="sis">
    <caption>Optional properties at construction time</caption>
    <tr>
      <th>Key</th>
      <th>Value type</th>
      <th>Description</th>
    </tr><tr>
      <td><code>"catalog"</code></td>
      <td><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link"><code>String</code></a></td>
      <td>The database catalog where the metadata schema is stored.</td>
    </tr><tr>
      <td><code>"classloader"</code></td>
      <td><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/ClassLoader.html" title="class or interface in java.lang" class="external-link"><code>ClassLoader</code></a></td>
      <td>The class loader to use for creating <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/reflect/Proxy.html" title="class or interface in java.lang.reflect" class="external-link"><code>Proxy</code></a> instances.</td>
    </tr><tr>
      <td><code>"maxStatements"</code></td>
      <td><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Integer.html" title="class or interface in java.lang" class="external-link"><code>Integer</code></a></td>
      <td>Maximal number of <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.sql/java/sql/PreparedStatement.html" title="class or interface in java.sql" class="external-link"><code>PreparedStatement</code></a>s that can be kept simultaneously open.</td>
    </tr><tr>
      <td><code>"maximumIdentifierLength"</code></td>
      <td><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Integer.html" title="class or interface in java.lang" class="external-link"><code>Integer</code></a></td>
      <td>The maximal number of characters allowed for primary keys.
          This is the value given to the <code>VARCHAR</code> type when creating new <code>"ID"</code> columns.</td>
    </tr><tr>
      <td><code>"maximumValueLength"</code></td>
      <td><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Integer.html" title="class or interface in java.lang" class="external-link"><code>Integer</code></a></td>
      <td>Maximal number of characters allowed in text columns. This is the parameter given to the <code>VARCHAR</code>
          type when creating new columns. Attempts to insert a text longer than this limit will typically throws
          a <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.sql/java/sql/SQLException.html" title="class or interface in java.sql" class="external-link"><code>SQLException</code></a>, but the exact behavior is database-dependent.</td>
    </tr><tr>
        <td><code>"columnCreationPolicy"</code></td>
        <td><a href="../ValueExistencePolicy.html" title="enum class in org.apache.sis.metadata"><code>ValueExistencePolicy</code></a></td>
        <td>Whether columns should be created only for non-empty attributes (<a href="../ValueExistencePolicy.html#NON_EMPTY"><code>NON_EMPTY</code></a>, the default) or for all attributes (<a href="../ValueExistencePolicy.html#ALL"><code>ALL</code></a>)</td>
    </tr>
  </table></div>
 <dl class="notes">
 <dt>Since:</dt>
 <dd>0.8</dd>

 <p><font size="-1">Defined in the <code>sis-metadata</code> module</font></p>
 </dl>
 </section>
 <section class="summary">
 <ul class="summary-list">
 <!-- =========== FIELD SUMMARY =========== -->
 <li>
 <section class="field-summary" id="field-summary">
 <h2>Field Summary</h2>
 <div class="inherited-list">
 <h3 id="fields-inherited-from-class-MetadataSource">Fields inherited from class&nbsp;<a href="MetadataSource.html" title="class in org.apache.sis.metadata.sql">MetadataSource</a></h3>
 <code><a href="MetadataSource.html#standard">standard</a></code></div>
 </section>
 </li>
 <!-- ======== CONSTRUCTOR SUMMARY ======== -->
 <li>
 <section class="constructor-summary" id="constructor-summary">
 <h2>Constructor Summary</h2>
 <div class="caption"><span>Constructors</span></div>
 <div class="summary-table two-column-summary">
 <div class="table-header col-first">Constructor</div>
 <div class="table-header col-last">Description</div>
 <div class="col-constructor-name even-row-color"><code><a href="#%3Cinit%3E(org.apache.sis.metadata.MetadataStandard,javax.sql.DataSource,java.lang.String,java.util.Map)" class="member-name-link">MetadataWriter</a><wbr>(<a href="../MetadataStandard.html" title="class in org.apache.sis.metadata">MetadataStandard</a>&nbsp;standard,
  <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.sql/javax/sql/DataSource.html" title="class or interface in javax.sql" class="external-link">DataSource</a>&nbsp;dataSource,
  <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>&nbsp;schema,
  <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/util/Map.html" title="class or interface in java.util" class="external-link">Map</a>&lt;<a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>,<wbr>?&gt;&nbsp;properties)</code></div>
 <div class="col-last even-row-color">
 <div class="block">Creates a new metadata writer.</div>
 </div>
 </div>
 </section>
 </li>
 <!-- ========== METHOD SUMMARY =========== -->
 <li>
 <section class="method-summary" id="method-summary">
 <h2>Method Summary</h2>
 <div id="method-summary-table">
 <div class="table-tabs" role="tablist" aria-orientation="horizontal"><button id="method-summary-table-tab0" role="tab" aria-selected="true" aria-controls="method-summary-table.tabpanel" tabindex="0" onkeydown="switchTab(event)" onclick="show('method-summary-table', 'method-summary-table', 3)" class="active-table-tab">All Methods</button><button id="method-summary-table-tab2" role="tab" aria-selected="false" aria-controls="method-summary-table.tabpanel" tabindex="-1" onkeydown="switchTab(event)" onclick="show('method-summary-table', 'method-summary-table-tab2', 3)" class="table-tab">Instance Methods</button><button id="method-summary-table-tab4" role="tab" aria-selected="false" aria-controls="method-summary-table.tabpanel" tabindex="-1" onkeydown="switchTab(event)" onclick="show('method-summary-table', 'method-summary-table-tab4', 3)" class="table-tab">Concrete Methods</button></div>
 <div id="method-summary-table.tabpanel" role="tabpanel">
 <div class="summary-table three-column-summary" aria-labelledby="method-summary-table-tab0">
 <div class="table-header col-first">Modifier and Type</div>
 <div class="table-header col-second">Method</div>
 <div class="table-header col-last">Description</div>
 <div class="col-first even-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a></code></div>
 <div class="col-second even-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code><a href="#add(java.lang.Object)" class="member-name-link">add</a><wbr>(<a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a>&nbsp;metadata)</code></div>
 <div class="col-last even-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4">
 <div class="block">Adds the given metadata object to the database, if it does not already exists.</div>
 </div>
 <div class="col-first odd-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code>protected <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a></code></div>
 <div class="col-second odd-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4"><code><a href="#suggestIdentifier(java.lang.Object,java.util.Map)" class="member-name-link">suggestIdentifier</a><wbr>(<a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a>&nbsp;metadata,
  <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/util/Map.html" title="class or interface in java.util" class="external-link">Map</a>&lt;<a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>,<wbr><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a>&gt;&nbsp;asValueMap)</code></div>
 <div class="col-last odd-row-color method-summary-table method-summary-table-tab2 method-summary-table-tab4">
 <div class="block">Suggests an identifier (primary key) to be used for the given metadata.</div>
 </div>
 </div>
 </div>
 </div>
 <div class="inherited-list">
 <h3 id="methods-inherited-from-class-MetadataSource">Methods inherited from class&nbsp;<a href="MetadataSource.html" title="class in org.apache.sis.metadata.sql">MetadataSource</a></h3>
 <code><a href="MetadataSource.html#close()">close</a>, <a href="MetadataSource.html#getProvided()">getProvided</a>, <a href="MetadataSource.html#getWarningFilter()">getWarningFilter</a>, <a href="MetadataSource.html#lookup(java.lang.Class,java.lang.String)">lookup</a>, <a href="MetadataSource.html#search(java.lang.Object)">search</a>, <a href="MetadataSource.html#setWarningFilter(java.util.logging.Filter)">setWarningFilter</a></code></div>
 <div class="inherited-list">
 <h3 id="methods-inherited-from-class-Object">Methods inherited from class&nbsp;<a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a></h3>
 <code><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#clone()" title="class or interface in java.lang" class="external-link">clone</a>, <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#equals(java.lang.Object)" title="class or interface in java.lang" class="external-link">equals</a>, <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#finalize()" title="class or interface in java.lang" class="external-link">finalize</a>, <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#getClass()" title="class or interface in java.lang" class="external-link">getClass</a>, <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#hashCode()" title="class or interface in java.lang" class="external-link">hashCode</a>, <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#notify()" title="class or interface in java.lang" class="external-link">notify</a>, <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#notifyAll()" title="class or interface in java.lang" class="external-link">notifyAll</a>, <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#toString()" title="class or interface in java.lang" class="external-link">toString</a>, <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#wait()" title="class or interface in java.lang" class="external-link">wait</a>, <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#wait(long)" title="class or interface in java.lang" class="external-link">wait</a>, <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html#wait(long,int)" title="class or interface in java.lang" class="external-link">wait</a></code></div>
 </section>
 </li>
 </ul>
 </section>
 <section class="details">
 <ul class="details-list">
 <!-- ========= CONSTRUCTOR DETAIL ======== -->
 <li>
 <section class="constructor-details" id="constructor-detail">
 <h2>Constructor Details</h2>
 <ul class="member-list">
 <li>
 <section class="detail" id="&lt;init&gt;(org.apache.sis.metadata.MetadataStandard,javax.sql.DataSource,java.lang.String,java.util.Map)">
 <h3>MetadataWriter</h3>
 <div class="member-signature"><span class="modifiers">public</span>&nbsp;<span class="element-name">MetadataWriter</span><wbr><span class="parameters">(<a href="../MetadataStandard.html" title="class in org.apache.sis.metadata">MetadataStandard</a>&nbsp;standard,
  <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.sql/javax/sql/DataSource.html" title="class or interface in javax.sql" class="external-link">DataSource</a>&nbsp;dataSource,
  <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>&nbsp;schema,
  <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/util/Map.html" title="class or interface in java.util" class="external-link">Map</a>&lt;<a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>,<wbr>?&gt;&nbsp;properties)</span></div>
 <div class="block">Creates a new metadata writer.</div>
 <dl class="notes">
 <dt>Parameters:</dt>
 <dd><code>standard</code> - the metadata standard to implement.</dd>
 <dd><code>dataSource</code> - the source for getting a connection to the database.</dd>
 <dd><code>schema</code> - the database schema were metadata tables are stored, or <code>null</code> if none.</dd>
 <dd><code>properties</code> - additional options, or <code>null</code> if none. See class javadoc for a description.</dd>
 </dl>
 </section>
 </li>
 </ul>
 </section>
 </li>
 <!-- ============ METHOD DETAIL ========== -->
 <li>
 <section class="method-details" id="method-detail">
 <h2>Method Details</h2>
 <ul class="member-list">
 <li>
 <section class="detail" id="add(java.lang.Object)">
 <h3>add</h3>
 <div class="member-signature"><span class="modifiers">public</span>&nbsp;<span class="return-type"><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a></span>&nbsp;<span class="element-name">add</span><wbr><span class="parameters">(<a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a>&nbsp;metadata)</span>
            throws <span class="exceptions"><a href="MetadataStoreException.html" title="class in org.apache.sis.metadata.sql">MetadataStoreException</a></span></div>
 <div class="block">Adds the given metadata object to the database, if it does not already exists.
  If the database already contains a metadata equals to the given one, then the
  database is left unchanged and the identifier of the existing metadata is returned.</div>
 <dl class="notes">
 <dt>Parameters:</dt>
 <dd><code>metadata</code> - the metadata object to add.</dd>
 <dt>Returns:</dt>
 <dd>the identifier (primary key) of the metadata just added,
          or the identifier of the existing metadata is one exists.</dd>
 <dt>Throws:</dt>
 <dd><code><a href="MetadataStoreException.html" title="class in org.apache.sis.metadata.sql">MetadataStoreException</a></code> - if the metadata object does not implement a metadata interface
          of the expected package, if an exception occurred while reading or writing the database.
          In such case, the database content is left unchanged
          (i.e. this method is a <cite>all or nothing</cite> operation).</dd>
 </dl>
 </section>
 </li>
 <li>
 <section class="detail" id="suggestIdentifier(java.lang.Object,java.util.Map)">
 <h3>suggestIdentifier</h3>
 <div class="member-signature"><span class="modifiers">protected</span>&nbsp;<span class="return-type"><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a></span>&nbsp;<span class="element-name">suggestIdentifier</span><wbr><span class="parameters">(<a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a>&nbsp;metadata,
  <a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/util/Map.html" title="class or interface in java.util" class="external-link">Map</a>&lt;<a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang" class="external-link">String</a>,<wbr><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/Object.html" title="class or interface in java.lang" class="external-link">Object</a>&gt;&nbsp;asValueMap)</span>
                             throws <span class="exceptions"><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.sql/java/sql/SQLException.html" title="class or interface in java.sql" class="external-link">SQLException</a></span></div>
 <div class="block">Suggests an identifier (primary key) to be used for the given metadata. This method is invoked automatically
  when a new metadata is about to be inserted in the database. The default implementation uses heuristic rules
  for a few "well known" metadata like <a href="http://www.geoapi.org/3.0/javadoc/org.opengis.geoapi/org/opengis/metadata/Identifier.html" title="class or interface in org.opengis.metadata" class="external-link"><code>Identifier</code></a> and <a href="http://www.geoapi.org/3.0/javadoc/org.opengis.geoapi/org/opengis/metadata/citation/Citation.html" title="class or interface in org.opengis.metadata.citation" class="external-link"><code>Citation</code></a>. Subclasses can override this
  method for implementing their own heuristic.

  <p>This method does not need to care about key collision.
  The caller will adds some suffix if this is necessary for differentiating otherwise identical identifiers.</p></div>
 <dl class="notes">
 <dt>Parameters:</dt>
 <dd><code>metadata</code> - the metadata instance for which to suggests an identifier.</dd>
 <dd><code>asValueMap</code> - a view of all metadata properties as a map.
                      Keys are <a href="../KeyNamePolicy.html#UML_IDENTIFIER">UML identifiers</a>.</dd>
 <dt>Returns:</dt>
 <dd>the proposed identifier, or <code>null</code> if this method does not have any suggestion.</dd>
 <dt>Throws:</dt>
 <dd><code><a href="https://docs.oracle.com/en/java/javase/16/docs/api/java.sql/java/sql/SQLException.html" title="class or interface in java.sql" class="external-link">SQLException</a></code> - if an access to the database was desired but failed.</dd>
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