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120 lines
4.8 KiB
HTML
120 lines
4.8 KiB
HTML
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<?xml version="1.0" encoding="UTF-8" standalone="no"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml">
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
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<title>DataAccessor.java</title>
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<link rel="stylesheet" href="gettingStarted.css" type="text/css" />
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<meta name="generator" content="DocBook XSL Stylesheets V1.73.2" />
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<link rel="start" href="index.html" title="Getting Started with Berkeley DB Java Edition" />
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<link rel="up" href="dpl_example.html" title="Chapter 6. A DPL Example" />
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<link rel="prev" href="mydbenv-persist.html" title="MyDbEnv" />
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<link rel="next" href="dpl_exampledatabaseput.html" title="ExampleDatabasePut.java" />
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</head>
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<body>
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<div xmlns="" class="navheader">
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<div class="libver">
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<p>Library Version 12.2.7.5</p>
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</div>
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<table width="100%" summary="Navigation header">
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<tr>
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<th colspan="3" align="center">DataAccessor.java</th>
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</tr>
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<tr>
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<td width="20%" align="left"><a accesskey="p" href="mydbenv-persist.html">Prev</a> </td>
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<th width="60%" align="center">Chapter 6. A DPL Example</th>
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<td width="20%" align="right"> <a accesskey="n" href="dpl_exampledatabaseput.html">Next</a></td>
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</tr>
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</table>
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<hr />
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</div>
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<div class="sect1" lang="en" xml:lang="en">
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<div class="titlepage">
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<div>
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<div>
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<h2 class="title" style="clear: both"><a id="dataaccessorclass"></a>DataAccessor.java</h2>
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</div>
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</div>
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</div>
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<p>
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Now that we have implemented our data classes,
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we can write a class that will provide
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convenient access to our primary and
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secondary indexes.
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Note that like our data classes, this class is shared by both our
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example programs.
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</p>
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<p>
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If you compare this class against our
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<code class="classname">Vendor</code> and
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<code class="classname">Inventory</code>
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class implementations, you will see that the
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primary and secondary indices declared there are
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referenced by this class.
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</p>
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<p>
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See <a class="xref" href="dpl_example.html#vendorclass" title="Vendor.java">Vendor.java</a>
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and
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<a class="xref" href="inventoryclass.html" title="Inventory.java">Inventory.java</a>
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for those implementations.
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</p>
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<pre class="programlisting">package persist.gettingStarted;
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import java.io.File;
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import com.sleepycat.je.DatabaseException;
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import com.sleepycat.persist.EntityStore;
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import com.sleepycat.persist.PrimaryIndex;
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import com.sleepycat.persist.SecondaryIndex;
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public class DataAccessor {
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// Open the indices
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public DataAccessor(EntityStore store)
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throws DatabaseException {
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// Primary key for Inventory classes
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inventoryBySku = store.getPrimaryIndex(
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String.class, Inventory.class);
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// Secondary key for Inventory classes
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// Last field in the getSecondaryIndex() method must be
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// the name of a class member; in this case, an Inventory.class
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// data member.
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inventoryByName = store.getSecondaryIndex(
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inventoryBySku, String.class, "itemName");
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// Primary key for Vendor class
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vendorByName = store.getPrimaryIndex(
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String.class, Vendor.class);
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}
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// Inventory Accessors
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PrimaryIndex<String,Inventory> inventoryBySku;
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SecondaryIndex<String,String,Inventory> inventoryByName;
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// Vendor Accessors
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PrimaryIndex<String,Vendor> vendorByName;
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} </pre>
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</div>
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<div class="navfooter">
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<hr />
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<table width="100%" summary="Navigation footer">
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<tr>
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<td width="40%" align="left"><a accesskey="p" href="mydbenv-persist.html">Prev</a> </td>
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<td width="20%" align="center">
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<a accesskey="u" href="dpl_example.html">Up</a>
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</td>
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<td width="40%" align="right"> <a accesskey="n" href="dpl_exampledatabaseput.html">Next</a></td>
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</tr>
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<tr>
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<td width="40%" align="left" valign="top">MyDbEnv </td>
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<td width="20%" align="center">
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<a accesskey="h" href="index.html">Home</a>
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</td>
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<td width="40%" align="right" valign="top"> ExampleDatabasePut.java</td>
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</tr>
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</table>
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</div>
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</body>
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</html>
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