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<p>
As mentioned above, we organize our primary and
secondary indexes using a specialize data
accessor class. The main reason for this class
to exist is to provide convenient access to all
the indexes in use for our entity class (see
the previous section, <a class="xref" href="persist_access.html#simpleentity" title="A Simple Entity Class">A Simple Entity Class</a>, for that
implementation).
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<p>
For a description on retrieving primary and
secondary indexes under the DPL, see
<a class="xref" href="persist_index.html" title="Chapter 4. Working with Indices">Working with Indices</a>
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<pre class="programlisting">package persist.gettingStarted;
import java.io.File;
import com.sleepycat.je.DatabaseException;
import com.sleepycat.persist.EntityStore;
import com.sleepycat.persist.PrimaryIndex;
import com.sleepycat.persist.SecondaryIndex;
public class SimpleDA {
// Open the indices
public SimpleDA(EntityStore store)
throws DatabaseException {
// Primary key for SimpleEntityClass classes
pIdx = store.getPrimaryIndex(
String.class, SimpleEntityClass.class);
// Secondary key for SimpleEntityClass classes
// Last field in the getSecondaryIndex() method must be
// the name of a class member; in this case, an
// SimpleEntityClass.class data member.
sIdx = store.getSecondaryIndex(
pIdx, String.class, "sKey");
}
// Index Accessors
PrimaryIndex&lt;String,SimpleEntityClass&gt; pIdx;
SecondaryIndex&lt;String,String,SimpleEntityClass&gt; sIdx;
} </pre>
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