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<p>
Now that we have implemented our data classes,
we can write a class that will provide
convenient access to our primary and
secondary indexes.
Note that like our data classes, this class is shared by both our
example programs.
</p>
<p>
If you compare this class against our
<tt class="classname">Vendor</tt> and
<tt class="classname">Inventory</tt>
class implementations, you will see that the
primary and secondary indices declared there are
referenced by this class.
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See <a href="dpl_example.html#vendorclass">Vendor.class</a>
and
<a href="inventoryclass.html">Inventory.class</a>
for those implementations.
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<pre class="programlisting">package persist.gettingStarted;
import java.io.File;
import com.sleepycat.db.DatabaseException;
import com.sleepycat.persist.EntityStore;
import com.sleepycat.persist.PrimaryIndex;
import com.sleepycat.persist.SecondaryIndex;
public class DataAccessor {
// Open the indices
public DataAccessor(EntityStore store)
throws DatabaseException {
// Primary key for Inventory classes
inventoryBySku = store.getPrimaryIndex(
String.class, Inventory.class);
// Secondary key for Inventory classes
// Last field in the getSecondaryIndex() method must be
// the name of a class member; in this case, an Inventory.class
// data member.
inventoryByName = store.getSecondaryIndex(
inventoryBySku, String.class, "itemName");
// Primary key for Vendor class
vendorByName = store.getPrimaryIndex(
String.class, Vendor.class);
}
// Inventory Accessors
PrimaryIndex<String,Inventory> inventoryBySku;
SecondaryIndex<String,String,Inventory> inventoryByName;
// Vendor Accessors
PrimaryIndex<String,Vendor> vendorByName;
} </pre>
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