mirror of
https://github.com/berkeleydb/libdb.git
synced 2024-11-17 01:26:25 +00:00
199 lines
8.5 KiB
HTML
199 lines
8.5 KiB
HTML
|
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
|
|||
|
|
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
|||
|
|
<html xmlns="http://www.w3.org/1999/xhtml">
|
|||
|
|
<head>
|
|||
|
|
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
|
|||
|
|
<title>Creating Tuple-Serial Entity Bindings</title>
|
|||
|
|
<link rel="stylesheet" href="gettingStarted.css" type="text/css" />
|
|||
|
|
<meta name="generator" content="DocBook XSL Stylesheets V1.73.2" />
|
|||
|
|
<link rel="start" href="index.html" title="Berkeley DB Collections Tutorial" />
|
|||
|
|
<link rel="up" href="Tuple.html" title="Chapter 5. Using Tuples" />
|
|||
|
|
<link rel="prev" href="tuplekeybindings.html" title="Creating Tuple Key Bindings" />
|
|||
|
|
<link rel="next" href="sortedcollections.html" title="Using Sorted Collections" />
|
|||
|
|
</head>
|
|||
|
|
<body>
|
|||
|
|
<div xmlns="" class="navheader">
|
|||
|
|
<div class="libver">
|
|||
|
|
<p>Library Version 11.2.5.2</p>
|
|||
|
|
</div>
|
|||
|
|
<table width="100%" summary="Navigation header">
|
|||
|
|
<tr>
|
|||
|
|
<th colspan="3" align="center">
|
|||
|
|
Creating Tuple-Serial Entity Bindings
|
|||
|
|
</th>
|
|||
|
|
</tr>
|
|||
|
|
<tr>
|
|||
|
|
<td width="20%" align="left"><a accesskey="p" href="tuplekeybindings.html">Prev</a> </td>
|
|||
|
|
<th width="60%" align="center">Chapter 5.
|
|||
|
|
Using Tuples
|
|||
|
|
</th>
|
|||
|
|
<td width="20%" align="right"> <a accesskey="n" href="sortedcollections.html">Next</a></td>
|
|||
|
|
</tr>
|
|||
|
|
</table>
|
|||
|
|
<hr />
|
|||
|
|
</div>
|
|||
|
|
<div class="sect1" lang="en" xml:lang="en">
|
|||
|
|
<div class="titlepage">
|
|||
|
|
<div>
|
|||
|
|
<div>
|
|||
|
|
<h2 class="title" style="clear: both"><a id="tuple-serialentitybindings"></a>
|
|||
|
|
Creating Tuple-Serial Entity Bindings
|
|||
|
|
</h2>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
<p>
|
|||
|
|
In the prior example serial keys and serial values were used,
|
|||
|
|
and the
|
|||
|
|
<a class="ulink" href="../../java/com/sleepycat/bind/serial/SerialSerialBinding.html" target="_top">SerialSerialBinding</a>
|
|||
|
|
|
|||
|
|
base class was used for entity bindings. In this example, tuple
|
|||
|
|
keys and serial values are used and therefore the
|
|||
|
|
<a class="ulink" href="../../java/com/sleepycat/bind/serial/TupleSerialBinding.html" target="_top">TupleSerialBinding</a>
|
|||
|
|
|
|||
|
|
base class is used for entity bindings.
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
As with any entity binding, a key and value is converted to an
|
|||
|
|
entity in the
|
|||
|
|
<a class="ulink" href="../../java/com/sleepycat/bind/serial/TupleSerialBinding.html#entryToObject(com.sleepycat.bind.tuple.TupleInput,%20java.lang.Object)" target="_top">TupleSerialBinding.entryToObject</a>
|
|||
|
|
|
|||
|
|
method, and from an entity to
|
|||
|
|
a key and value in the
|
|||
|
|
<a class="ulink" href="../../java/com/sleepycat/bind/serial/TupleSerialBinding.html#objectToKey(java.lang.Object,%20com.sleepycat.db.DatabaseEntry)" target="_top">TupleSerialBinding.objectToKey</a>
|
|||
|
|
|
|||
|
|
and
|
|||
|
|
<a class="ulink" href="../../java/com/sleepycat/bind/serial/TupleSerialBinding.html#objectToData(java.lang.Object)" target="_top">TupleSerialBinding.objectToData</a>
|
|||
|
|
|
|||
|
|
methods. But since keys are
|
|||
|
|
stored as tuples, not as serialized objects, key fields are read
|
|||
|
|
and written using the
|
|||
|
|
<a class="ulink" href="../../java/com/sleepycat/bind/tuple/TupleInput.html" target="_top">TupleInput</a>
|
|||
|
|
|
|||
|
|
and
|
|||
|
|
<a class="ulink" href="../../java/com/sleepycat/bind/tuple/TupleOutput.html" target="_top">TupleOutput</a>
|
|||
|
|
|
|||
|
|
parameters.
|
|||
|
|
</p>
|
|||
|
|
<p>
|
|||
|
|
The <code class="classname">SampleViews</code> class contains the modified entity
|
|||
|
|
binding classes that were defined in the prior example:
|
|||
|
|
<code class="classname">PartBinding</code>, <code class="classname">SupplierBinding</code> and
|
|||
|
|
<code class="classname">ShipmentBinding</code>.
|
|||
|
|
</p>
|
|||
|
|
<a id="tuple_partbinding"></a>
|
|||
|
|
<pre class="programlisting"><strong class="userinput"><code>import com.sleepycat.bind.serial.TupleSerialBinding;
|
|||
|
|
import com.sleepycat.bind.tuple.TupleInput;
|
|||
|
|
import com.sleepycat.bind.tuple.TupleOutput;
|
|||
|
|
...</code></strong>
|
|||
|
|
public class SampleViews
|
|||
|
|
{
|
|||
|
|
...
|
|||
|
|
private static class PartBinding extends <strong class="userinput"><code>TupleSerialBinding</code></strong>
|
|||
|
|
{
|
|||
|
|
private PartBinding(ClassCatalog classCatalog, <strong class="userinput"><code>Class dataClass</code></strong>)
|
|||
|
|
{
|
|||
|
|
super(classCatalog, dataClass);
|
|||
|
|
}
|
|||
|
|
public Object entryToObject(<strong class="userinput"><code>TupleInput</code></strong> keyInput, Object dataInput)
|
|||
|
|
{
|
|||
|
|
<strong class="userinput"><code> String number = keyInput.readString();</code></strong>
|
|||
|
|
PartData data = (PartData) dataInput;
|
|||
|
|
return new Part(<strong class="userinput"><code>number</code></strong>, data.getName(), data.getColor(),
|
|||
|
|
data.getWeight(), data.getCity());
|
|||
|
|
}
|
|||
|
|
public void objectToKey(Object object, TupleOutput output)
|
|||
|
|
{
|
|||
|
|
Part part = (Part) object;
|
|||
|
|
<strong class="userinput"><code> output.writeString(part.getNumber());</code></strong>
|
|||
|
|
}
|
|||
|
|
public Object objectToData(Object object)
|
|||
|
|
{
|
|||
|
|
Part part = (Part) object;
|
|||
|
|
return new PartData(part.getName(), part.getColor(),
|
|||
|
|
part.getWeight(), part.getCity());
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
...
|
|||
|
|
private static class SupplierBinding extends <strong class="userinput"><code>TupleSerialBinding</code></strong>
|
|||
|
|
{
|
|||
|
|
private SupplierBinding(ClassCatalog classCatalog, <strong class="userinput"><code>Class dataClass</code></strong>)
|
|||
|
|
{
|
|||
|
|
super(classCatalog, dataClass);
|
|||
|
|
}
|
|||
|
|
public Object entryToObject(<strong class="userinput"><code>TupleInput</code></strong> keyInput, Object dataInput)
|
|||
|
|
{
|
|||
|
|
<strong class="userinput"><code> String number = keyInput.readString();</code></strong>
|
|||
|
|
SupplierData data = (SupplierData) dataInput;
|
|||
|
|
return new Supplier(<strong class="userinput"><code>number</code></strong>, data.getName(),
|
|||
|
|
data.getStatus(), data.getCity());
|
|||
|
|
}
|
|||
|
|
public void objectToKey(Object object, TupleOutput output)
|
|||
|
|
{
|
|||
|
|
Supplier supplier = (Supplier) object;
|
|||
|
|
<strong class="userinput"><code> output.writeString(supplier.getNumber());</code></strong>
|
|||
|
|
}
|
|||
|
|
public Object objectToData(Object object)
|
|||
|
|
{
|
|||
|
|
Supplier supplier = (Supplier) object;
|
|||
|
|
return new SupplierData(supplier.getName(),
|
|||
|
|
supplier.getStatus(),
|
|||
|
|
supplier.getCity());
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
...
|
|||
|
|
private static class ShipmentBinding extends <strong class="userinput"><code>TupleSerialBinding</code></strong>
|
|||
|
|
{
|
|||
|
|
private ShipmentBinding(ClassCatalog classCatalog, <strong class="userinput"><code>Class dataClass</code></strong>)
|
|||
|
|
{
|
|||
|
|
super(classCatalog, dataClass);
|
|||
|
|
}
|
|||
|
|
public Object entryToObject(<strong class="userinput"><code>TupleInput</code></strong> keyInput, Object dataInput)
|
|||
|
|
{
|
|||
|
|
<strong class="userinput"><code> String partNumber = keyInput.readString();
|
|||
|
|
String supplierNumber = keyInput.readString();</code></strong>
|
|||
|
|
ShipmentData data = (ShipmentData) dataInput;
|
|||
|
|
return new Shipment(<strong class="userinput"><code>partNumber, supplierNumber</code></strong>,
|
|||
|
|
data.getQuantity());
|
|||
|
|
}
|
|||
|
|
public void objectToKey(Object object, TupleOutput output)
|
|||
|
|
{
|
|||
|
|
Shipment shipment = (Shipment) object;
|
|||
|
|
<strong class="userinput"><code> output.writeString(shipment.getPartNumber());
|
|||
|
|
output.writeString(shipment.getSupplierNumber());</code></strong>
|
|||
|
|
}
|
|||
|
|
public Object objectToData(Object object)
|
|||
|
|
{
|
|||
|
|
Shipment shipment = (Shipment) object;
|
|||
|
|
return new ShipmentData(shipment.getQuantity());
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
...
|
|||
|
|
} </pre>
|
|||
|
|
</div>
|
|||
|
|
<div class="navfooter">
|
|||
|
|
<hr />
|
|||
|
|
<table width="100%" summary="Navigation footer">
|
|||
|
|
<tr>
|
|||
|
|
<td width="40%" align="left"><a accesskey="p" href="tuplekeybindings.html">Prev</a> </td>
|
|||
|
|
<td width="20%" align="center">
|
|||
|
|
<a accesskey="u" href="Tuple.html">Up</a>
|
|||
|
|
</td>
|
|||
|
|
<td width="40%" align="right"> <a accesskey="n" href="sortedcollections.html">Next</a></td>
|
|||
|
|
</tr>
|
|||
|
|
<tr>
|
|||
|
|
<td width="40%" align="left" valign="top">
|
|||
|
|
Creating Tuple Key Bindings
|
|||
|
|
</td>
|
|||
|
|
<td width="20%" align="center">
|
|||
|
|
<a accesskey="h" href="index.html">Home</a>
|
|||
|
|
</td>
|
|||
|
|
<td width="40%" align="right" valign="top">
|
|||
|
|
Using Sorted Collections
|
|||
|
|
</td>
|
|||
|
|
</tr>
|
|||
|
|
</table>
|
|||
|
|
</div>
|
|||
|
|
</body>
|
|||
|
|
</html>
|