| <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> |
| <!-- NewPage --> |
| <html lang="en"> |
| <head> |
| <!-- Generated by javadoc --> |
| <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> |
| <title>ReaderLifecycle (Drill : 1.20.3 API)</title> |
| <link rel="stylesheet" type="text/css" href="../../../../../../../../../stylesheet.css" title="Style"> |
| <script type="text/javascript" src="../../../../../../../../../script.js"></script> |
| </head> |
| <body> |
| <script type="text/javascript"><!-- |
| try { |
| if (location.href.indexOf('is-external=true') == -1) { |
| parent.document.title="ReaderLifecycle (Drill : 1.20.3 API)"; |
| } |
| } |
| catch(err) { |
| } |
| //--> |
| var methods = {"i0":10,"i1":10,"i2":10,"i3":10,"i4":10,"i5":10,"i6":10,"i7":10,"i8":10,"i9":10,"i10":10,"i11":10,"i12":10,"i13":10,"i14":10,"i15":10}; |
| var tabs = {65535:["t0","All Methods"],2:["t2","Instance Methods"],8:["t4","Concrete Methods"]}; |
| var altColor = "altColor"; |
| var rowColor = "rowColor"; |
| var tableTab = "tableTab"; |
| var activeTableTab = "activeTableTab"; |
| </script> |
| <noscript> |
| <div>JavaScript is disabled on your browser.</div> |
| </noscript> |
| <!-- ========= START OF TOP NAVBAR ======= --> |
| <div class="topNav"><a name="navbar.top"> |
| <!-- --> |
| </a> |
| <div class="skipNav"><a href="#skip.navbar.top" title="Skip navigation links">Skip navigation links</a></div> |
| <a name="navbar.top.firstrow"> |
| <!-- --> |
| </a> |
| <ul class="navList" title="Navigation"> |
| <li><a href="../../../../../../../../../overview-summary.html">Overview</a></li> |
| <li><a href="package-summary.html">Package</a></li> |
| <li class="navBarCell1Rev">Class</li> |
| <li><a href="class-use/ReaderLifecycle.html">Use</a></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"> |
| <li><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/OutputBatchBuilder.MapSource.html" title="class in org.apache.drill.exec.physical.impl.scan.v3.lifecycle"><span class="typeNameLink">Prev Class</span></a></li> |
| <li><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ScanEventListener.html" title="class in org.apache.drill.exec.physical.impl.scan.v3.lifecycle"><span class="typeNameLink">Next Class</span></a></li> |
| </ul> |
| <ul class="navList"> |
| <li><a href="../../../../../../../../../index.html?org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html" target="_top">Frames</a></li> |
| <li><a href="ReaderLifecycle.html" target="_top">No Frames</a></li> |
| </ul> |
| <ul class="navList" id="allclasses_navbar_top"> |
| <li><a href="../../../../../../../../../allclasses-noframe.html">All Classes</a></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> |
| </div> |
| <div> |
| <ul class="subNavList"> |
| <li>Summary: </li> |
| <li>Nested | </li> |
| <li><a href="#field.summary">Field</a> | </li> |
| <li><a href="#constructor.summary">Constr</a> | </li> |
| <li><a href="#method.summary">Method</a></li> |
| </ul> |
| <ul class="subNavList"> |
| <li>Detail: </li> |
| <li><a href="#field.detail">Field</a> | </li> |
| <li><a href="#constructor.detail">Constr</a> | </li> |
| <li><a href="#method.detail">Method</a></li> |
| </ul> |
| </div> |
| <a name="skip.navbar.top"> |
| <!-- --> |
| </a></div> |
| <!-- ========= END OF TOP NAVBAR ========= --> |
| <!-- ======== START OF CLASS DATA ======== --> |
| <div class="header"> |
| <div class="subTitle">org.apache.drill.exec.physical.impl.scan.v3.lifecycle</div> |
| <h2 title="Class ReaderLifecycle" class="title">Class ReaderLifecycle</h2> |
| </div> |
| <div class="contentContainer"> |
| <ul class="inheritance"> |
| <li><a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">java.lang.Object</a></li> |
| <li> |
| <ul class="inheritance"> |
| <li>org.apache.drill.exec.physical.impl.scan.v3.lifecycle.ReaderLifecycle</li> |
| </ul> |
| </li> |
| </ul> |
| <div class="description"> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <dl> |
| <dt>All Implemented Interfaces:</dt> |
| <dd><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html" title="interface in org.apache.drill.exec.physical.impl.scan">RowBatchReader</a></dd> |
| </dl> |
| <hr> |
| <br> |
| <pre>public class <span class="typeNameLabel">ReaderLifecycle</span> |
| extends <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</a> |
| implements <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html" title="interface in org.apache.drill.exec.physical.impl.scan">RowBatchReader</a></pre> |
| <div class="block">Manages the schema and batch construction for a managed reader. Allows the |
| reader itself to be as simple as possible. This class implements the basic |
| <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html" title="interface in org.apache.drill.exec.physical.impl.scan"><code>RowBatchReader</code></a> protocol based on three methods, and converts it to |
| the two-method protocol of the managed reader. The <code>open()</code> call of the |
| <code>RowBatchReader</code> is combined with the constructor of the |
| <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/ManagedReader.html" title="interface in org.apache.drill.exec.physical.impl.scan.v3"><code>ManagedReader</code></a>, enforcing the rule that the managed reader is created |
| just-in-time when it is to be used, which avoids accidentally holding |
| resources for the life of the scan. Also allows most of the reader's fields |
| to be <code>final</code>. |
| <p> |
| Coordinates the components that wrap a reader to create the final output |
| batch: |
| <ul> |
| <li>The actual reader which loads (possibly a subset of) the columns requested |
| from the input source.</li> |
| <li>Implicit columns manager instance which populates implicit file columns, |
| partition columns, and Drill's internal implicit columns.</li> |
| <li>The missing columns handler which "makes up" values for projected columns |
| not read by the reader.</li> |
| <li>Batch assembler, which combines the three sources of vectors to create |
| the output batch with the schema specified by the schema tracker.</li> |
| </ul> |
| <p> |
| This class coordinates the reader-visible aspects of the scan: |
| <ul> |
| <li>The <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/SchemaNegotiator.html" title="interface in org.apache.drill.exec.physical.impl.scan.v3"><code>SchemaNegotiator</code></a> (or subclass) which provides schema-related |
| input to the reader and which creates the reader's <a href="../../../../../../../../../org/apache/drill/exec/physical/resultSet/ResultSetLoader.html" title="interface in org.apache.drill.exec.physical.resultSet"><code>ResultSetLoader</code></a>, |
| among other tasks. The schema negotiator is specific to each kind of scan and |
| is thus created via the <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/ScanLifecycleBuilder.html" title="class in org.apache.drill.exec.physical.impl.scan.v3"><code>ScanLifecycleBuilder</code></a>.</li> |
| <li>The reader, which is designed to be as simple as possible, with all |
| generic overhead tasks handled by this "shim" between the scan operator and |
| the actual reader implementation.</li> |
| </ul> |
| <p> |
| The reader is schema-driven. See <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/schema/ScanSchemaTracker.html" title="interface in org.apache.drill.exec.physical.impl.scan.v3.schema"><code>ScanSchemaTracker</code></a> for an overview. |
| <ul> |
| <li>The reader is given a <i>reader input schema</i>, via the schema |
| negotiator, which specifies the desired output schema. The schema can be |
| fully dynamic (a wildcard), fully defined (a prior reader already chose |
| column types), or a hybrid.</li> |
| <li>The reader can load a subset of columns. Those that are left out become |
| "missing columns" to be filled in by this class.</li> |
| <li>The <i>reader output schema</i> along with implicit and missing columns, |
| together define the scan's output schema.</li> |
| </ul> |
| <p> |
| The framework handles the projection task so the reader does not have to |
| worry about it. Reading an unwanted column is low cost: the result set loader |
| will have provided a "dummy" column writer that simply discards the value. |
| This is just as fast as having the reader use if-statements or a table to |
| determine which columns to save.</div> |
| </li> |
| </ul> |
| </div> |
| <div class="summary"> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <!-- =========== FIELD SUMMARY =========== --> |
| <ul class="blockList"> |
| <li class="blockList"><a name="field.summary"> |
| <!-- --> |
| </a> |
| <h3>Field Summary</h3> |
| <table class="memberSummary" border="0" cellpadding="3" cellspacing="0" summary="Field Summary table, listing fields, and an explanation"> |
| <caption><span>Fields</span><span class="tabEnd"> </span></caption> |
| <tr> |
| <th class="colFirst" scope="col">Modifier and Type</th> |
| <th class="colLast" scope="col">Field and Description</th> |
| </tr> |
| <tr class="altColor"> |
| <td class="colFirst"><code>protected <a href="../../../../../../../../../org/apache/drill/exec/record/metadata/TupleMetadata.html" title="interface in org.apache.drill.exec.record.metadata">TupleMetadata</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#readerInputSchema">readerInputSchema</a></span></code> </td> |
| </tr> |
| <tr class="rowColor"> |
| <td class="colFirst"><code>protected <a href="../../../../../../../../../org/apache/drill/exec/physical/resultSet/ResultSetLoader.html" title="interface in org.apache.drill.exec.physical.resultSet">ResultSetLoader</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#tableLoader">tableLoader</a></span></code> </td> |
| </tr> |
| </table> |
| </li> |
| </ul> |
| <!-- ======== CONSTRUCTOR SUMMARY ======== --> |
| <ul class="blockList"> |
| <li class="blockList"><a name="constructor.summary"> |
| <!-- --> |
| </a> |
| <h3>Constructor Summary</h3> |
| <table class="memberSummary" border="0" cellpadding="3" cellspacing="0" summary="Constructor Summary table, listing constructors, and an explanation"> |
| <caption><span>Constructors</span><span class="tabEnd"> </span></caption> |
| <tr> |
| <th class="colOne" scope="col">Constructor and Description</th> |
| </tr> |
| <tr class="altColor"> |
| <td class="colOne"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#ReaderLifecycle-org.apache.drill.exec.physical.impl.scan.v3.lifecycle.ScanLifecycle-long-">ReaderLifecycle</a></span>(<a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ScanLifecycle.html" title="class in org.apache.drill.exec.physical.impl.scan.v3.lifecycle">ScanLifecycle</a> scanLifecycle, |
| long limit)</code> </td> |
| </tr> |
| </table> |
| </li> |
| </ul> |
| <!-- ========== METHOD SUMMARY =========== --> |
| <ul class="blockList"> |
| <li class="blockList"><a name="method.summary"> |
| <!-- --> |
| </a> |
| <h3>Method Summary</h3> |
| <table class="memberSummary" border="0" cellpadding="3" cellspacing="0" summary="Method Summary table, listing methods, and an explanation"> |
| <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="t4" class="tableTab"><span><a href="javascript:show(8);">Concrete Methods</a></span><span class="tabEnd"> </span></span></caption> |
| <tr> |
| <th class="colFirst" scope="col">Modifier and Type</th> |
| <th class="colLast" scope="col">Method and Description</th> |
| </tr> |
| <tr id="i0" class="altColor"> |
| <td class="colFirst"><code><a href="../../../../../../../../../org/apache/drill/exec/physical/resultSet/ResultSetLoader.html" title="interface in org.apache.drill.exec.physical.resultSet">ResultSetLoader</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#buildLoader--">buildLoader</a></span>()</code> </td> |
| </tr> |
| <tr id="i1" class="rowColor"> |
| <td class="colFirst"><code>void</code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#close--">close</a></span>()</code> |
| <div class="block">Release resources.</div> |
| </td> |
| </tr> |
| <tr id="i2" class="altColor"> |
| <td class="colFirst"><code>boolean</code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#defineSchema--">defineSchema</a></span>()</code> |
| <div class="block">Called for the first reader within a scan.</div> |
| </td> |
| </tr> |
| <tr id="i3" class="rowColor"> |
| <td class="colFirst"><code><a href="../../../../../../../../../org/apache/drill/common/exceptions/CustomErrorContext.html" title="interface in org.apache.drill.common.exceptions">CustomErrorContext</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#errorContext--">errorContext</a></span>()</code> </td> |
| </tr> |
| <tr id="i4" class="altColor"> |
| <td class="colFirst"><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/MissingColumnHandlerBuilder.html" title="class in org.apache.drill.exec.physical.impl.scan.v3.lifecycle">MissingColumnHandlerBuilder</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#missingColumnsBuilder-org.apache.drill.exec.record.metadata.TupleMetadata-">missingColumnsBuilder</a></span>(<a href="../../../../../../../../../org/apache/drill/exec/record/metadata/TupleMetadata.html" title="interface in org.apache.drill.exec.record.metadata">TupleMetadata</a> readerSchema)</code> </td> |
| </tr> |
| <tr id="i5" class="rowColor"> |
| <td class="colFirst"><code><a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#name--">name</a></span>()</code> |
| <div class="block">Name used when reporting errors.</div> |
| </td> |
| </tr> |
| <tr id="i6" class="altColor"> |
| <td class="colFirst"><code>boolean</code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#next--">next</a></span>()</code> |
| <div class="block">Read the next batch.</div> |
| </td> |
| </tr> |
| <tr id="i7" class="rowColor"> |
| <td class="colFirst"><code>boolean</code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#open--">open</a></span>()</code> |
| <div class="block">Setup the record reader.</div> |
| </td> |
| </tr> |
| <tr id="i8" class="altColor"> |
| <td class="colFirst"><code><a href="../../../../../../../../../org/apache/drill/exec/record/VectorContainer.html" title="class in org.apache.drill.exec.record">VectorContainer</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#output--">output</a></span>()</code> |
| <div class="block">Return the container with the reader's output.</div> |
| </td> |
| </tr> |
| <tr id="i9" class="rowColor"> |
| <td class="colFirst"><code><a href="../../../../../../../../../org/apache/drill/exec/record/metadata/TupleMetadata.html" title="interface in org.apache.drill.exec.record.metadata">TupleMetadata</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#readerInputSchema--">readerInputSchema</a></span>()</code> </td> |
| </tr> |
| <tr id="i10" class="altColor"> |
| <td class="colFirst"><code><a href="../../../../../../../../../org/apache/drill/exec/record/metadata/TupleMetadata.html" title="interface in org.apache.drill.exec.record.metadata">TupleMetadata</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#readerOutputSchema--">readerOutputSchema</a></span>()</code> </td> |
| </tr> |
| <tr id="i11" class="rowColor"> |
| <td class="colFirst"><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ScanLifecycle.html" title="class in org.apache.drill.exec.physical.impl.scan.v3.lifecycle">ScanLifecycle</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#scanLifecycle--">scanLifecycle</a></span>()</code> </td> |
| </tr> |
| <tr id="i12" class="altColor"> |
| <td class="colFirst"><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/ScanLifecycleBuilder.html" title="class in org.apache.drill.exec.physical.impl.scan.v3">ScanLifecycleBuilder</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#scanOptions--">scanOptions</a></span>()</code> </td> |
| </tr> |
| <tr id="i13" class="rowColor"> |
| <td class="colFirst"><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/schema/ScanSchemaTracker.html" title="interface in org.apache.drill.exec.physical.impl.scan.v3.schema">ScanSchemaTracker</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#schemaTracker--">schemaTracker</a></span>()</code> </td> |
| </tr> |
| <tr id="i14" class="altColor"> |
| <td class="colFirst"><code>int</code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#schemaVersion--">schemaVersion</a></span>()</code> |
| <div class="block">Return the version of the schema returned by <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#output--"><code>RowBatchReader.output()</code></a>.</div> |
| </td> |
| </tr> |
| <tr id="i15" class="rowColor"> |
| <td class="colFirst"><code><a href="../../../../../../../../../org/apache/drill/exec/physical/resultSet/ResultSetLoader.html" title="interface in org.apache.drill.exec.physical.resultSet">ResultSetLoader</a></code></td> |
| <td class="colLast"><code><span class="memberNameLink"><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html#tableLoader--">tableLoader</a></span>()</code> </td> |
| </tr> |
| </table> |
| <ul class="blockList"> |
| <li class="blockList"><a name="methods.inherited.from.class.java.lang.Object"> |
| <!-- --> |
| </a> |
| <h3>Methods inherited from class java.lang.<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</a></h3> |
| <code><a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#clone--" title="class or interface in java.lang">clone</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#equals-java.lang.Object-" title="class or interface in java.lang">equals</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#finalize--" title="class or interface in java.lang">finalize</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#getClass--" title="class or interface in java.lang">getClass</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#hashCode--" title="class or interface in java.lang">hashCode</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#notify--" title="class or interface in java.lang">notify</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#notifyAll--" title="class or interface in java.lang">notifyAll</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#toString--" title="class or interface in java.lang">toString</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#wait--" title="class or interface in java.lang">wait</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#wait-long-" title="class or interface in java.lang">wait</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html?is-external=true#wait-long-int-" title="class or interface in java.lang">wait</a></code></li> |
| </ul> |
| </li> |
| </ul> |
| </li> |
| </ul> |
| </div> |
| <div class="details"> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <!-- ============ FIELD DETAIL =========== --> |
| <ul class="blockList"> |
| <li class="blockList"><a name="field.detail"> |
| <!-- --> |
| </a> |
| <h3>Field Detail</h3> |
| <a name="readerInputSchema"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>readerInputSchema</h4> |
| <pre>protected final <a href="../../../../../../../../../org/apache/drill/exec/record/metadata/TupleMetadata.html" title="interface in org.apache.drill.exec.record.metadata">TupleMetadata</a> readerInputSchema</pre> |
| </li> |
| </ul> |
| <a name="tableLoader"> |
| <!-- --> |
| </a> |
| <ul class="blockListLast"> |
| <li class="blockList"> |
| <h4>tableLoader</h4> |
| <pre>protected <a href="../../../../../../../../../org/apache/drill/exec/physical/resultSet/ResultSetLoader.html" title="interface in org.apache.drill.exec.physical.resultSet">ResultSetLoader</a> tableLoader</pre> |
| </li> |
| </ul> |
| </li> |
| </ul> |
| <!-- ========= CONSTRUCTOR DETAIL ======== --> |
| <ul class="blockList"> |
| <li class="blockList"><a name="constructor.detail"> |
| <!-- --> |
| </a> |
| <h3>Constructor Detail</h3> |
| <a name="ReaderLifecycle-org.apache.drill.exec.physical.impl.scan.v3.lifecycle.ScanLifecycle-long-"> |
| <!-- --> |
| </a> |
| <ul class="blockListLast"> |
| <li class="blockList"> |
| <h4>ReaderLifecycle</h4> |
| <pre>public ReaderLifecycle(<a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ScanLifecycle.html" title="class in org.apache.drill.exec.physical.impl.scan.v3.lifecycle">ScanLifecycle</a> scanLifecycle, |
| long limit)</pre> |
| </li> |
| </ul> |
| </li> |
| </ul> |
| <!-- ============ METHOD DETAIL ========== --> |
| <ul class="blockList"> |
| <li class="blockList"><a name="method.detail"> |
| <!-- --> |
| </a> |
| <h3>Method Detail</h3> |
| <a name="scanLifecycle--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>scanLifecycle</h4> |
| <pre>public <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ScanLifecycle.html" title="class in org.apache.drill.exec.physical.impl.scan.v3.lifecycle">ScanLifecycle</a> scanLifecycle()</pre> |
| </li> |
| </ul> |
| <a name="readerInputSchema--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>readerInputSchema</h4> |
| <pre>public <a href="../../../../../../../../../org/apache/drill/exec/record/metadata/TupleMetadata.html" title="interface in org.apache.drill.exec.record.metadata">TupleMetadata</a> readerInputSchema()</pre> |
| </li> |
| </ul> |
| <a name="errorContext--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>errorContext</h4> |
| <pre>public <a href="../../../../../../../../../org/apache/drill/common/exceptions/CustomErrorContext.html" title="interface in org.apache.drill.common.exceptions">CustomErrorContext</a> errorContext()</pre> |
| </li> |
| </ul> |
| <a name="schemaTracker--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>schemaTracker</h4> |
| <pre>public <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/schema/ScanSchemaTracker.html" title="interface in org.apache.drill.exec.physical.impl.scan.v3.schema">ScanSchemaTracker</a> schemaTracker()</pre> |
| </li> |
| </ul> |
| <a name="scanOptions--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>scanOptions</h4> |
| <pre>public <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/ScanLifecycleBuilder.html" title="class in org.apache.drill.exec.physical.impl.scan.v3">ScanLifecycleBuilder</a> scanOptions()</pre> |
| </li> |
| </ul> |
| <a name="name--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>name</h4> |
| <pre>public <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a> name()</pre> |
| <div class="block"><span class="descfrmTypeLabel">Description copied from interface: <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#name--">RowBatchReader</a></code></span></div> |
| <div class="block">Name used when reporting errors. Can simply be the class name.</div> |
| <dl> |
| <dt><span class="overrideSpecifyLabel">Specified by:</span></dt> |
| <dd><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#name--">name</a></code> in interface <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html" title="interface in org.apache.drill.exec.physical.impl.scan">RowBatchReader</a></code></dd> |
| <dt><span class="returnLabel">Returns:</span></dt> |
| <dd>display name for errors</dd> |
| </dl> |
| </li> |
| </ul> |
| <a name="tableLoader--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>tableLoader</h4> |
| <pre>public <a href="../../../../../../../../../org/apache/drill/exec/physical/resultSet/ResultSetLoader.html" title="interface in org.apache.drill.exec.physical.resultSet">ResultSetLoader</a> tableLoader()</pre> |
| </li> |
| </ul> |
| <a name="open--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>open</h4> |
| <pre>public boolean open()</pre> |
| <div class="block"><span class="descfrmTypeLabel">Description copied from interface: <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#open--">RowBatchReader</a></code></span></div> |
| <div class="block">Setup the record reader. Called just before the first call |
| to <code>next()</code>. Allocate resources here, not in the constructor. |
| Example: open files, allocate buffers, etc.</div> |
| <dl> |
| <dt><span class="overrideSpecifyLabel">Specified by:</span></dt> |
| <dd><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#open--">open</a></code> in interface <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html" title="interface in org.apache.drill.exec.physical.impl.scan">RowBatchReader</a></code></dd> |
| <dt><span class="returnLabel">Returns:</span></dt> |
| <dd>true if the reader is open and ready to read (possibly no) |
| rows. false for a "soft" failure in which no schema or data is available, |
| but the scanner should not fail, it should move onto another reader</dd> |
| </dl> |
| </li> |
| </ul> |
| <a name="buildLoader--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>buildLoader</h4> |
| <pre>public <a href="../../../../../../../../../org/apache/drill/exec/physical/resultSet/ResultSetLoader.html" title="interface in org.apache.drill.exec.physical.resultSet">ResultSetLoader</a> buildLoader()</pre> |
| </li> |
| </ul> |
| <a name="defineSchema--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>defineSchema</h4> |
| <pre>public boolean defineSchema()</pre> |
| <div class="block"><span class="descfrmTypeLabel">Description copied from interface: <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#defineSchema--">RowBatchReader</a></code></span></div> |
| <div class="block">Called for the first reader within a scan. Allows the reader to |
| provide an empty batch with only the schema filled in. Readers that |
| are "early schema" (know the schema up front) should return true |
| and create an empty batch. Readers that are "late schema" should |
| return false. In that case, the scan operator will ask the reader |
| to load an actual data batch, and infer the schema from that batch. |
| <p> |
| This step is optional and is purely for performance.</div> |
| <dl> |
| <dt><span class="overrideSpecifyLabel">Specified by:</span></dt> |
| <dd><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#defineSchema--">defineSchema</a></code> in interface <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html" title="interface in org.apache.drill.exec.physical.impl.scan">RowBatchReader</a></code></dd> |
| <dt><span class="returnLabel">Returns:</span></dt> |
| <dd>true if this reader can (and has) defined an empty batch |
| to describe the schema, false otherwise</dd> |
| </dl> |
| </li> |
| </ul> |
| <a name="next--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>next</h4> |
| <pre>public boolean next()</pre> |
| <div class="block"><span class="descfrmTypeLabel">Description copied from interface: <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#next--">RowBatchReader</a></code></span></div> |
| <div class="block">Read the next batch. Reading continues until either EOF, |
| or until the mutator indicates that the batch is full. |
| The batch is considered valid if it is non-empty. Returning |
| <code>true</code> with an empty batch is valid, and is helpful on |
| the very first batch (returning schema only.) An empty batch |
| with a <code>false</code> return code indicates EOF and the batch |
| will be discarded. A non-empty batch along with a <code>false</code> |
| return result indicates a final, valid batch, but that EOF was |
| reached and no more data is available. |
| <p> |
| This somewhat complex protocol avoids the need to allocate a |
| final batch just to find out that no more data is available; |
| it allows EOF to be returned along with the final batch.</div> |
| <dl> |
| <dt><span class="overrideSpecifyLabel">Specified by:</span></dt> |
| <dd><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#next--">next</a></code> in interface <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html" title="interface in org.apache.drill.exec.physical.impl.scan">RowBatchReader</a></code></dd> |
| <dt><span class="returnLabel">Returns:</span></dt> |
| <dd><code>true</code> if more data may be available (and so |
| <code>next()</code> should be called again, <code>false</code> to indicate |
| that EOF was reached</dd> |
| </dl> |
| </li> |
| </ul> |
| <a name="missingColumnsBuilder-org.apache.drill.exec.record.metadata.TupleMetadata-"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>missingColumnsBuilder</h4> |
| <pre>public <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/MissingColumnHandlerBuilder.html" title="class in org.apache.drill.exec.physical.impl.scan.v3.lifecycle">MissingColumnHandlerBuilder</a> missingColumnsBuilder(<a href="../../../../../../../../../org/apache/drill/exec/record/metadata/TupleMetadata.html" title="interface in org.apache.drill.exec.record.metadata">TupleMetadata</a> readerSchema)</pre> |
| </li> |
| </ul> |
| <a name="readerOutputSchema--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>readerOutputSchema</h4> |
| <pre>public <a href="../../../../../../../../../org/apache/drill/exec/record/metadata/TupleMetadata.html" title="interface in org.apache.drill.exec.record.metadata">TupleMetadata</a> readerOutputSchema()</pre> |
| </li> |
| </ul> |
| <a name="output--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>output</h4> |
| <pre>public <a href="../../../../../../../../../org/apache/drill/exec/record/VectorContainer.html" title="class in org.apache.drill.exec.record">VectorContainer</a> output()</pre> |
| <div class="block"><span class="descfrmTypeLabel">Description copied from interface: <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#output--">RowBatchReader</a></code></span></div> |
| <div class="block">Return the container with the reader's output. This method is called |
| at two times: |
| <ul> |
| <li>Directly after the call to <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#open--"><code>RowBatchReader.open()</code></a>. If the data source |
| can provide a schema at open time, then the reader should provide an |
| empty batch with the schema set. The scanner will return this schema |
| downstream to inform other operators of the schema.</li> |
| <li>Directly after a successful call to <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#next--"><code>RowBatchReader.next()</code></a> to retrieve |
| the batch produced by that call. (No call is made if <code>next()</code> |
| returns false.</li> |
| </ul> |
| Note that most operators require the same vectors be present in |
| each container. So, in practice, a reader must return the same |
| container, and same set of vectors, on each call.</div> |
| <dl> |
| <dt><span class="overrideSpecifyLabel">Specified by:</span></dt> |
| <dd><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#output--">output</a></code> in interface <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html" title="interface in org.apache.drill.exec.physical.impl.scan">RowBatchReader</a></code></dd> |
| <dt><span class="returnLabel">Returns:</span></dt> |
| <dd>a vector container, with the record count and schema |
| set, that announces the schema after <code>open()</code> (optional) |
| or returns rows read after <code>next()</code> (required)</dd> |
| </dl> |
| </li> |
| </ul> |
| <a name="schemaVersion--"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>schemaVersion</h4> |
| <pre>public int schemaVersion()</pre> |
| <div class="block"><span class="descfrmTypeLabel">Description copied from interface: <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#schemaVersion--">RowBatchReader</a></code></span></div> |
| <div class="block">Return the version of the schema returned by <a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#output--"><code>RowBatchReader.output()</code></a>. The schema |
| is assumed to start at -1 (no schema). The reader is free to use any |
| numbering system it likes as long as: |
| <ul> |
| <li>The numbers are non-negative, and increase (by any increment),</li> |
| <li>Numbers between successive calls are idential if the batch schemas are |
| identical,</li> |
| <li>The number increases if a batch has a different schema than the |
| previous batch.</li> |
| </ul> |
| Numbers increment (or not) on calls to <code>next()</code>. Thus Two successive |
| calls to this method should return the same number if no <code>next()</code> |
| call lies between. |
| <p> |
| If the reader can return a schema on open (so-called "early-schema), then |
| this method must return a non-negative version number, even if the schema |
| happens to be empty (such as reading an empty file.) |
| <p> |
| However, if the reader cannot return a schema on open (so-called "late |
| schema"), then this method must return -1 (and <code>output()</code> must |
| return null) to indicate now schema is available when called before the |
| first call to <code>next()</code>. |
| <p> |
| No calls will be made to this method before <code>open()</code> after |
| close(){@code or after {@code next()} returns false. The implementation |
| is thus not required to handle these cases.</div> |
| <dl> |
| <dt><span class="overrideSpecifyLabel">Specified by:</span></dt> |
| <dd><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#schemaVersion--">schemaVersion</a></code> in interface <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html" title="interface in org.apache.drill.exec.physical.impl.scan">RowBatchReader</a></code></dd> |
| <dt><span class="returnLabel">Returns:</span></dt> |
| <dd>the schema version, or -1 if no schema version is yet available</dd> |
| </dl> |
| </li> |
| </ul> |
| <a name="close--"> |
| <!-- --> |
| </a> |
| <ul class="blockListLast"> |
| <li class="blockList"> |
| <h4>close</h4> |
| <pre>public void close()</pre> |
| <div class="block"><span class="descfrmTypeLabel">Description copied from interface: <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#close--">RowBatchReader</a></code></span></div> |
| <div class="block">Release resources. Called just after a failure, when the scanner |
| is cancelled, or after <code>next()</code> returns EOF. Release |
| all resources and close files. Guaranteed to be called if |
| <code>open()</code> returns normally; will not be called if <code>open()</code> |
| throws an exception.</div> |
| <dl> |
| <dt><span class="overrideSpecifyLabel">Specified by:</span></dt> |
| <dd><code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html#close--">close</a></code> in interface <code><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/RowBatchReader.html" title="interface in org.apache.drill.exec.physical.impl.scan">RowBatchReader</a></code></dd> |
| </dl> |
| </li> |
| </ul> |
| </li> |
| </ul> |
| </li> |
| </ul> |
| </div> |
| </div> |
| <!-- ========= END OF CLASS DATA ========= --> |
| <!-- ======= START OF BOTTOM NAVBAR ====== --> |
| <div class="bottomNav"><a name="navbar.bottom"> |
| <!-- --> |
| </a> |
| <div class="skipNav"><a href="#skip.navbar.bottom" title="Skip navigation links">Skip navigation links</a></div> |
| <a name="navbar.bottom.firstrow"> |
| <!-- --> |
| </a> |
| <ul class="navList" title="Navigation"> |
| <li><a href="../../../../../../../../../overview-summary.html">Overview</a></li> |
| <li><a href="package-summary.html">Package</a></li> |
| <li class="navBarCell1Rev">Class</li> |
| <li><a href="class-use/ReaderLifecycle.html">Use</a></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"> |
| <li><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/OutputBatchBuilder.MapSource.html" title="class in org.apache.drill.exec.physical.impl.scan.v3.lifecycle"><span class="typeNameLink">Prev Class</span></a></li> |
| <li><a href="../../../../../../../../../org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ScanEventListener.html" title="class in org.apache.drill.exec.physical.impl.scan.v3.lifecycle"><span class="typeNameLink">Next Class</span></a></li> |
| </ul> |
| <ul class="navList"> |
| <li><a href="../../../../../../../../../index.html?org/apache/drill/exec/physical/impl/scan/v3/lifecycle/ReaderLifecycle.html" target="_top">Frames</a></li> |
| <li><a href="ReaderLifecycle.html" target="_top">No Frames</a></li> |
| </ul> |
| <ul class="navList" id="allclasses_navbar_bottom"> |
| <li><a href="../../../../../../../../../allclasses-noframe.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> |
| </div> |
| <div> |
| <ul class="subNavList"> |
| <li>Summary: </li> |
| <li>Nested | </li> |
| <li><a href="#field.summary">Field</a> | </li> |
| <li><a href="#constructor.summary">Constr</a> | </li> |
| <li><a href="#method.summary">Method</a></li> |
| </ul> |
| <ul class="subNavList"> |
| <li>Detail: </li> |
| <li><a href="#field.detail">Field</a> | </li> |
| <li><a href="#constructor.detail">Constr</a> | </li> |
| <li><a href="#method.detail">Method</a></li> |
| </ul> |
| </div> |
| <a name="skip.navbar.bottom"> |
| <!-- --> |
| </a></div> |
| <!-- ======== END OF BOTTOM NAVBAR ======= --> |
| <p class="legalCopy"><small>Copyright © 1970 <a href="https://www.apache.org/">The Apache Software Foundation</a>. All rights reserved.</small></p> |
| </body> |
| </html> |
