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		Using Transient Fields in an Entity Binding
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            <h2 class="title" style="clear: both"><a id="transientfieldsinbinding"></a>
		Using Transient Fields in an Entity Binding
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      <p>
    The entity bindings from the prior example have been changed in
	this example to use the entity object both as a value object and an
	entity object.
</p>
      <p>
    Before, the <tt class="methodname">entryToObject()</tt> method combined the
	deserialized value object with the key fields to create a new
	entity object. Now, this method uses the deserialized object
	directly as an entity, and initializes its key using the fields
	read from the key tuple.
</p>
      <p>
    Before, the <tt class="methodname">objectToData()</tt> method constructed a new value
	object using information in the entity. Now it simply returns the
	entity. Nothing needs to be changed in the entity, since the
	transient key fields won't be serialized.
</p>
      <a id="sentity_partbinding"></a>
      <pre class="programlisting">import com.sleepycat.bind.serial.ClassCatalog;
...
public class SampleViews
{
    ...
    private static class PartBinding extends TupleSerialBinding
    {
        private PartBinding(ClassCatalog classCatalog, Class dataClass)
        {
            super(classCatalog, dataClass);
        }

public Object entryToObject(TupleInput keyInput, Object dataInput)
        {
            String number = keyInput.readString();
<b class="userinput"><tt>            Part part = (Part) dataInput;
            part.setKey(number);
            return part;</tt></b>
        }

public void objectToKey(Object object, TupleOutput output)
        {
            Part part = (Part) object;
            output.writeString(part.getNumber());
        }

public Object objectToData(Object object)
        {
<b class="userinput"><tt>            return object;</tt></b>
        }
    }

private static class SupplierBinding extends TupleSerialBinding
    {
        private SupplierBinding(ClassCatalog classCatalog, Class dataClass)
        {
            super(classCatalog, dataClass);
        }

public Object entryToObject(TupleInput keyInput, Object dataInput)
        {
            String number = keyInput.readString();
<b class="userinput"><tt>            Supplier supplier = (Supplier) dataInput;
            supplier.setKey(number);
            return supplier;</tt></b>
        }

public void objectToKey(Object object, TupleOutput output)
        {
            Supplier supplier = (Supplier) object;
            output.writeString(supplier.getNumber());
        }

public Object objectToData(Object object)
        {
<b class="userinput"><tt>            return object;</tt></b>
        }
    }

private static class ShipmentBinding extends TupleSerialBinding
    {
        private ShipmentBinding(ClassCatalog classCatalog, Class dataClass)
        {
            super(classCatalog, dataClass);
        }

public Object entryToObject(TupleInput keyInput, Object dataInput)
        {
            String partNumber = keyInput.readString();
            String supplierNumber = keyInput.readString();
<b class="userinput"><tt>            Shipment shipment = (Shipment) dataInput;
            shipment.setKey(partNumber, supplierNumber);
            return shipment;</tt></b>
        }

public void objectToKey(Object object, TupleOutput output)
        {
            Shipment shipment = (Shipment) object;
            output.writeString(shipment.getPartNumber());
            output.writeString(shipment.getSupplierNumber());
        }

public Object objectToData(Object object)
        {
<b class="userinput"><tt>            return object;</tt></b>
        }
    }
} </pre>
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