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<H2>

com.sleepycat.persist
 
Interface EntityIndex&lt;K,V&gt;</H2>
<DL>
<DT>All Known Implementing Classes: <DD><A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist">PrimaryIndex</A>, <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="class in com.sleepycat.persist">SecondaryIndex</A></DD>
</DL>
<HR>
<DL>
<DT><PRE>public interface EntityIndex&lt;K,V&gt;</DL>
</PRE>

The interface for accessing keys and entities via a primary or secondary
 index.

<code>EntityIndex</code> objects are thread-safe. Multiple threads may safely
 call the methods of a shared <code>EntityIndex</code> object.

An index is conceptually a map. {key:value} mappings are
 stored in the index and accessed by key. In fact, for interoperability with
 other libraries that use the standard Java <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/util/Map.html" title="class or interface in java.util"><CODE>Map</CODE></A> or <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/util/SortedMap.html" title="class or interface in java.util"><CODE>SortedMap</CODE></A>
 interfaces, an <code>EntityIndex</code> may be accessed via these standard
 interfaces by calling the <A HREF="../../../com/sleepycat/persist/EntityIndex.html#map()"><CODE>map()</CODE></A> or <A HREF="../../../com/sleepycat/persist/EntityIndex.html#sortedMap()"><CODE>sortedMap()</CODE></A> methods.

<code>EntityIndex</code> is an interface that is implemented by several
 classes in this package for different purposes. Depending on the context,
 the key type (K) and value type (V) of the index take on different meanings.
 The different classes that implement <code>EntityIndex</code> are:
 <ul>
 <li><A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist"><CODE>PrimaryIndex</CODE></A> maps primary keys to entities.</li>
 <li><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="class in com.sleepycat.persist"><CODE>SecondaryIndex</CODE></A> maps secondary keys to entities.</li>
 <li><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex"><CODE>SecondaryIndex.keysIndex</CODE></A> maps secondary keys to primary
 keys.</li>
 <li><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#subIndex(SK)"><CODE>SecondaryIndex.subIndex(SK)</CODE></A> maps primary keys to entities, for the
 subset of entities having a specified secondary key.</li>
 </ul>

In all cases, the index key type (K) is a primary or secondary key class.
 The index value type (V) is an entity class in all cases except for a <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex"><CODE>SecondaryIndex.keysIndex</CODE></A>, when it is a primary key class.

In the following example, a <code>Employee</code> entity with a <code>MANY_TO_ONE</code> secondary key is defined.

<pre class="code">
 @Entity
 class Employee {

@PrimaryKey
     long id;

@SecondaryKey(relate=MANY_TO_ONE)
     String department;

String name;

private Employee() {}
 }</pre>

Consider that we have stored the entities below:

<table class="code" border="1">
 <tr><th colspan="3">Entities</th></tr>
 <tr><th>ID</th><th>Department</th><th>Name</th></tr>
 <tr><td>1</td><td>Engineering</td><td>Jane Smith</td></tr>
 <tr><td>2</td><td>Sales</td><td>Joan Smith</td></tr>
 <tr><td>3</td><td>Engineering</td><td>John Smith</td></tr>
 <tr><td>4</td><td>Sales</td><td>Jim Smith</td></tr>
 </table>

<A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist"><CODE>PrimaryIndex</CODE></A> maps primary keys to entities:

<pre class="code">
 <code>PrimaryIndex&lt;Long,Employee&gt;</code> primaryIndex =
 store.getPrimaryIndex(Long.class, Employee.class);</pre>

<table class="code" border="1">
 <tr><th colspan="4">primaryIndex</th></tr>
 <tr><th>Primary Key</th><th colspan="3">Entity</th></tr>
 <tr><td>1</td><td>1</td><td>Engineering</td><td>Jane Smith</td></tr>
 <tr><td>2</td><td>2</td><td>Sales</td><td>Joan Smith</td></tr>
 <tr><td>3</td><td>3</td><td>Engineering</td><td>John Smith</td></tr>
 <tr><td>4</td><td>4</td><td>Sales</td><td>Jim Smith</td></tr>
 </table>

<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="class in com.sleepycat.persist"><CODE>SecondaryIndex</CODE></A> maps secondary keys to entities:

<pre class="code">
 <code>SecondaryIndex&lt;String,Long,Employee&gt;</code> secondaryIndex =
 store.getSecondaryIndex(primaryIndex, String.class, "department");</pre>

<table class="code" border="1">
 <tr><th colspan="4">secondaryIndex</th></tr>
 <tr><th>Secondary Key</th><th colspan="3">Entity</th></tr>
 <tr><td>Engineering</td><td>1</td><td>Engineering</td><td>Jane Smith</td></tr>
 <tr><td>Engineering</td><td>3</td><td>Engineering</td><td>John Smith</td></tr>
 <tr><td>Sales</td><td>2</td><td>Sales</td><td>Joan Smith</td></tr>
 <tr><td>Sales</td><td>4</td><td>Sales</td><td>Jim Smith</td></tr>
 </table>

<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex"><CODE>SecondaryIndex.keysIndex</CODE></A> maps secondary keys to primary
 keys:

<pre class="code">
 <code>EntityIndex&lt;String,Long&gt;</code> keysIndex = secondaryIndex.keysIndex();</pre>

<table class="code" border="1">
 <tr><th colspan="4">keysIndex</th></tr>
 <tr><th>Secondary Key</th><th colspan="3">Primary Key</th></tr>
 <tr><td>Engineering</td><td>1</td></tr>
 <tr><td>Engineering</td><td>3</td></tr>
 <tr><td>Sales</td><td>2</td></tr>
 <tr><td>Sales</td><td>4</td></tr>
 </table>

<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#subIndex(SK)"><CODE>SecondaryIndex.subIndex(SK)</CODE></A> maps primary keys to entities, for the
 subset of entities having a specified secondary key:

<pre class="code">
 <code>EntityIndex&lt;Long,Entity&gt;</code> subIndex = secondaryIndex.subIndex("Engineering");</pre>

<table class="code" border="1">
 <tr><th colspan="4">subIndex</th></tr>
 <tr><th>Primary Key</th><th colspan="3">Entity</th></tr>
 <tr><td>1</td><td>1</td><td>Engineering</td><td>Jane Smith</td></tr>
 <tr><td>3</td><td>3</td><td>Engineering</td><td>John Smith</td></tr>
 </table>

<h3>Accessing the Index</h3>

An <code>EntityIndex</code> provides a variety of methods for retrieving
 entities from an index. It also provides methods for deleting entities.
 However, it does not provide methods for inserting and updating. To insert
 and update entities, use the <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html#put(E)"><CODE>PrimaryIndex.put(E)</CODE></A> family of methods in
 the <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist"><CODE>PrimaryIndex</CODE></A> class.

An <code>EntityIndex</code> supports two mechanisms for retrieving
 entities:
 <ol>
 <li>The <A HREF="../../../com/sleepycat/persist/EntityIndex.html#get(K)"><CODE>get(K)</CODE></A> method returns a single value for a given key. If there
 are multiple values with the same secondary key (duplicates), it returns the
 first entity in the duplicate set.</li>
 <li>An <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist"><CODE>EntityCursor</CODE></A> can be obtained using the <A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys()"><CODE>keys()</CODE></A> and
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities()"><CODE>entities()</CODE></A> family of methods. A cursor can be used to return all
 values in the index, including duplicates. A cursor can also be used to
 return values within a specified range of keys.</li>
 </ol>

Using the example entities above, calling <A HREF="../../../com/sleepycat/persist/EntityIndex.html#get(K)"><CODE>get(K)</CODE></A> on the primary
 index will always return the employee with the given ID, or null if no such
 ID exists. But calling <A HREF="../../../com/sleepycat/persist/EntityIndex.html#get(K)"><CODE>get(K)</CODE></A> on the secondary index will retrieve
 the first employee in the given department, which may not be very
 useful:

<pre class="code">
 Employee emp = primaryIndex.get(1); // Returns by unique ID
 emp = secondaryIndex.get("Engineering"); // Returns first in department</pre>

Using a cursor, you can iterate through all duplicates in the secondary
 index:

<pre class="code">
 <code>EntityCursor&lt;Employee&gt;</code> cursor = secondaryIndex.entities();
 try {
 for (Employee entity : cursor) {
 if (entity.department.equals("Engineering")) {
 // Do something with the entity...
 }
 }
 } finally {
 cursor.close();
 }</pre>

But for a large database it is much more efficient to iterate over only
 those entities with the secondary key you're searching for. This could be
 done by restricting a cursor to a range of keys:

<pre class="code">
 <code>EntityCursor&lt;Employee&gt;</code> cursor =
 secondaryIndex.entities("Engineering", true, "Engineering", true);
 try {
 for (Employee entity : cursor) {
 // Do something with the entity...
 }
 } finally {
 cursor.close();
 }</pre>

However, when you are interested only in the entities with a particular
 secondary key value, it is more convenient to use a sub-index:

<pre class="code">
 <code>EntityIndex&lt;Long,Entity&gt;</code> subIndex = secondaryIndex.subIndex("Engineering");
 <code>EntityCursor&lt;Employee&gt;</code> cursor = subIndex.entities();
 try {
 for (Employee entity : cursor) {
 // Do something with the entity...
 }
 } finally {
 cursor.close();
 }</pre>

In addition to being more convenient than a cursor range, a sub-index
 allows retrieving by primary key:

<pre class="code">
 Employee emp = subIndex.get(1);</pre>

When using a sub-index, all operations performed on the sub-index are
 restricted to the single key that was specified when the sub-index was
 created. For example, the following returns null because employee 2 is not
 in the Engineering department and therefore is not part of the
 sub-index:

<pre class="code">
 Employee emp = subIndex.get(2);</pre>

For more information on using cursors and cursor ranges, see <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist"><CODE>EntityCursor</CODE></A>.

Note that when using an index, keys and values are stored and retrieved
 by value not by reference. In other words, if an entity object is stored
 and then retrieved, or retrieved twice, each object will be a separate
 instance. For example, in the code below the assertion will always
 fail.
 <pre class="code">
 MyKey key = ...;
 MyEntity entity1 = index.get(key);
 MyEntity entity2 = index.get(key);
 assert entity1 == entity2; // always fails!
 </pre>

<h3>Deleting from the Index</h3>

Any type of index may be used to delete entities with a specified key by
 calling <A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(K)"><CODE>delete(K)</CODE></A>. The important thing to keep in mind is that
 all entities with the specified key are deleted. In a primary index,
 at most a single entity is deleted:

<pre class="code">
 primaryIndex.delete(1); // Deletes a single employee by unique ID</pre>

But in a secondary index, multiple entities may be deleted:

<pre class="code">
 secondaryIndex.delete("Engineering"); // Deletes all Engineering employees</pre>

This begs this question: How can a single entity be deleted without
 knowing its primary key? The answer is to use cursors. After locating an
 entity using a cursor, the entity can be deleted by calling <A HREF="../../../com/sleepycat/persist/EntityCursor.html#delete()"><CODE>EntityCursor.delete()</CODE></A>.

<h3>Transactions</h3>

Transactions can be used to provide standard ACID (Atomicity,
 Consistency, Integrity and Durability) guarantees when retrieving, storing
 and deleting entities. This section provides a brief overview of how to use
 transactions with the Direct Persistence Layer. For more information on
 using transactions, see <a
 href="../../../../gsg_txn/JAVA/index.html">Writing
 Transactional Applications</a>.

Transactions may be used only with a transactional <A HREF="../../../com/sleepycat/persist/EntityStore.html" title="class in com.sleepycat.persist"><CODE>EntityStore</CODE></A>,
 which is one for which <A HREF="../../../com/sleepycat/persist/StoreConfig.html#setTransactional(boolean)"><CODE>StoreConfig.setTransactional(true)</CODE></A> has been called. Likewise, a
 transactional store may only be used with a transactional <A HREF="../../../com/sleepycat/db/Environment.html" title="class in com.sleepycat.db"><CODE>Environment</CODE></A>, which is one for which <A HREF="../../../com/sleepycat/db/EnvironmentConfig.html#setTransactional(boolean)"><CODE>EnvironmentConfig.setTransactional(true)</CODE></A>
 has been called. For example:

<pre class="code">
 EnvironmentConfig envConfig = new EnvironmentConfig();
 envConfig.setTransactional(true);
 envConfig.setAllowCreate(true);
 Environment env = new Environment(new File("/my/data"), envConfig);

StoreConfig storeConfig = new StoreConfig();
 storeConfig.setTransactional(true);
 storeConfig.setAllowCreate(true);
 EntityStore store = new EntityStore(env, "myStore", storeConfig);</pre>

Transactions are represented by <A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db"><CODE>Transaction</CODE></A> objects, which are
 part of the <A HREF="../../../com/sleepycat/db/package-summary.html"><CODE>Base API</CODE></A>. Transactions are created
 using the <A HREF="../../../com/sleepycat/db/Environment.html#beginTransaction(com.sleepycat.db.Transaction, com.sleepycat.db.TransactionConfig)"><CODE>Environment.beginTransaction</CODE></A>
 method.

A transaction will include all operations for which the transaction
 object is passed as a method argument. All retrieval, storage and deletion
 methods have an optional <A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db"><CODE>Transaction</CODE></A> parameter for this purpose.
 When a transaction is passed to a method that opens a cursor, all retrieval,
 storage and deletion operations performed using that cursor will be included
 in the transaction.

A transaction may be committed by calling <A HREF="../../../com/sleepycat/db/Transaction.html#commit()"><CODE>Transaction.commit()</CODE></A> or
 aborted by calling <A HREF="../../../com/sleepycat/db/Transaction.html#abort()"><CODE>Transaction.abort()</CODE></A>. For example, two employees
 may be deleted atomically with a transaction; other words, either both are
 deleted or neither is deleted:

<pre class="code">
 Transaction txn = env.beginTransaction(null, null);
 try {
 primaryIndex.delete(txn, 1);
 primaryIndex.delete(txn, 2);
 txn.commit();
 txn = null;
 } finally {
 if (txn != null) {
 txn.abort();
 }
 }</pre>

WARNING: Transactions must always be committed or aborted to
 prevent resource leaks which could lead to the index becoming unusable or
 cause an <code>OutOfMemoryError</code>. To ensure that a transaction is
 aborted in the face of exceptions, call <A HREF="../../../com/sleepycat/db/Transaction.html#abort()"><CODE>Transaction.abort()</CODE></A> in a
 finally block.

For a transactional store, storage and deletion operations are always
 transaction protected, whether or not a transaction is explicitly used. A
 null transaction argument means to perform the operation using auto-commit,
 or the implied thread transaction if an XAEnvironment is being used. A
 transaction is automatically started as part of the operation and is
 automatically committed if the operation completes successfully. The
 transaction is automatically aborted if an exception occurs during the
 operation, and the exception is re-thrown to the caller. For example, each
 employee is deleted using a an auto-commit transaction below, but it is
 possible that employee 1 will be deleted and employee 2 will not be deleted,
 if an error or crash occurs while deleting employee 2:

<pre class="code">
 primaryIndex.delete(null, 1);
 primaryIndex.delete(null, 2);</pre>

When retrieving entities, a null transaction argument means to perform
 the operation non-transactionally. The operation is performed outside the
 scope of any transaction, without providing transactional ACID guarantees.
 If an implied thread transaction is present (i.e. if an XAEnvironment is
 being used), that transaction is used. When a non-transactional store is
 used, transactional ACID guarantees are also not provided.

For non-transactional and auto-commit usage, overloaded signatures for
 retrieval, storage and deletion methods are provided to avoid having to pass
 a null transaction argument. For example, <A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(K)"><CODE>delete(K)</CODE></A> may be called
 instead of <A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(com.sleepycat.db.Transaction, K)"><CODE>delete(Transaction,Object)</CODE></A>. For example, the following
 code is equivalent to the code above where null was passed for the
 transaction:

<pre class="code">
 primaryIndex.delete(1);
 primaryIndex.delete(2);</pre>

For retrieval methods the overloaded signatures also include an optional
 <A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db"><CODE>LockMode</CODE></A> parameter, and overloaded signatures for opening cursors
 include an optional <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db"><CODE>CursorConfig</CODE></A> parameter. These parameters are
 described further below in the Locking and Lock Modes section.

<h3>Transactions and Cursors</h3>

There are two special consideration when using cursors with transactions.
 First, for a transactional store, a non-null transaction must be passed to
 methods that open a cursor if that cursor will be used to delete or update
 entities. Cursors do not perform auto-commit when a null transaction is
 explicitly passed or implied by the method signature. For example, the
 following code will throw <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db"><CODE>DatabaseException</CODE></A> when the <A HREF="../../../com/sleepycat/persist/EntityCursor.html#delete()"><CODE>EntityCursor.delete()</CODE></A> method is called:

<pre class="code">
 // Does not work with a transactional store!
 <code>EntityCursor&lt;Employee&gt;</code> cursor = primaryIndex.entities();
 try {
 for (Employee entity : cursor) {
 cursor.delete(); // Will throw DatabaseException.
 }
 } finally {
 cursor.close();
 }</pre>

Instead, the <A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)"><CODE>entities(Transaction,CursorConfig)</CODE></A> signature must
 be used and a non-null transaction must be passed:

<pre class="code">
 <code>EntityCursor&lt;Employee&gt;</code> cursor = primaryIndex.entities(txn, null);
 try {
 for (Employee entity : cursor) {
 cursor.delete();
 }
 } finally {
 cursor.close();
 }</pre>

The second consideration is that error handling is more complex when
 using both transactions and cursors, for the following reasons:
 <ol>
 <li>When an exception occurs, the transaction should be aborted.</li>
 <li>Cursors must be closed whether or not an exception occurs.</li>
 <li>Cursors must be closed before committing or aborting the
 transaction.</li>
 </ol>

For example:

<pre class="code">
 Transaction txn = env.beginTransaction(null, null);
 <code>EntityCursor&lt;Employee&gt;</code> cursor = null;
 try {
 cursor = primaryIndex.entities(txn, null);
 for (Employee entity : cursor) {
 cursor.delete();
 }
 cursor.close();
 cursor = null;
 txn.commit();
 txn = null;
 } finally {
 if (cursor != null) {
 cursor.close();
 }
 if (txn != null) {
 txn.abort();
 }
 }</pre>

<h3>Locking and Lock Modes</h3>

This section provides a brief overview of locking and describes how lock
 modes are used with the Direct Persistence Layer. For more information on
 locking, see <a
 href="../../../../gsg_txn/JAVA/index.html">Writing
 Transactional Applications</a>.

When using transactions, locks are normally acquired on each entity that
 is retrieved or stored. The locks are used to isolate one transaction from
 another. Locks are normally released only when the transaction is committed
 or aborted.

When not using transactions, locks are also normally acquired on each
 entity that is retrieved or stored. However, these locks are released when
 the operation is complete. When using cursors, in order to provide
 cursor stability locks are held until the cursor is moved to a
 different entity or closed.

This default locking behavior provides full transactional ACID guarantees
 and cursor stability. However, application performance can sometimes be
 improved by compromising these guarantees. As described in <a
 href="../../../../gsg_txn/JAVA/index.html">Writing
 Transactional Applications</a>, the <A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db"><CODE>LockMode</CODE></A> and <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db"><CODE>CursorConfig</CODE></A> parameters are two of the mechanisms that can be used to make
 compromises.

For example, imagine that you need an approximate count of all entities
 matching certain criterion, and it is acceptable for entities to be changed
 by other threads or other transactions while performing this query. <A HREF="../../../com/sleepycat/db/LockMode.html#READ_UNCOMMITTED"><CODE>LockMode.READ_UNCOMMITTED</CODE></A> can be used to perform the retrievals without
 acquiring any locks. This reduces memory consumption, does less processing,
 and can improve concurrency.

<pre class="code">
 <code>EntityCursor&lt;Employee&gt;</code> cursor = primaryIndex.entities(txn, null);
 try {
 Employee entity;
 while ((entity = cursor.next(LockMode.READ_UNCOMMITTED)) != null) {
 // Examine the entity and accumulate totals...
 }
 } finally {
 cursor.close();
 }</pre>

The <A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db"><CODE>LockMode</CODE></A> parameter specifies locking behavior on a
 per-operation basis. If null or <A HREF="../../../com/sleepycat/db/LockMode.html#DEFAULT"><CODE>LockMode.DEFAULT</CODE></A> is specified, the
 default lock mode is used.

It is also possible to specify the default locking behavior for a cursor
 using <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db"><CODE>CursorConfig</CODE></A>. The example below is equivalent to the example
 above:

<pre class="code">
 CursorConfig config = new CursorConfig();
 config.setReadUncommitted(true);
 <code>EntityCursor&lt;Employee&gt;</code> cursor = primaryIndex.entities(txn, config);
 try {
 Employee entity;
 while ((entity = cursor.next()) != null) {
 // Examine the entity and accumulate totals...
 }
 } finally {
 cursor.close();
 }</pre>

The use of other lock modes, cursor configuration, and transaction
 configuration are discussed in <a
 href="../../../../gsg_txn/JAVA/index.html">Writing
 Transactional Applications</a>.

Deadlock handling is another important topic discussed in <a
 href="../../../../gsg_txn/JAVA/index.html">Writing
 Transactional Applications</a>. To go along with that material, here we
 show a deadlock handling loop in the context of the Direct Persistence
 Layer. The example below shows deleting all entities in a primary index in
 a single transaction. If a deadlock occurs, the transaction is aborted and
 the operation is retried.

<pre class="code">
 int retryCount = 0;
 boolean retry = true;
 while (retry) {
 Transaction txn = env.beginTransaction(null, null);
 <code>EntityCursor&lt;Employee&gt;</code> cursor = null;
 try {
 cursor = primaryIndex.entities(txn, null);
 for (Employee entity : cursor) {
 cursor.delete();
 }
 cursor.close();
 cursor = null;
 txn.commit();
 txn = null;
 retry = false;
 } catch (DeadlockException e) {
 retryCount += 1;
 if (retryCount &gt;= MAX_DEADLOCK_RETRIES) {
 throw e;
 }
 } finally {
 if (cursor != null) {
 cursor.close();
 }
 if (txn != null) {
 txn.abort();
 }
 }
 }</pre>

<h3>Low Level Access</h3>

Each Direct Persistence Layer index is associated with an underlying
 <A HREF="../../../com/sleepycat/db/Database.html" title="class in com.sleepycat.db"><CODE>Database</CODE></A> or <A HREF="../../../com/sleepycat/db/SecondaryDatabase.html" title="class in com.sleepycat.db"><CODE>SecondaryDatabase</CODE></A> defined in the <A HREF="../../../com/sleepycat/db/package-summary.html"><CODE>Base API</CODE></A>. At this level, an index is a Btree managed by
 the Berkeley DB Java Edition transactional storage engine. Although you may
 never need to work at the <code>Base API</code> level, keep in mind that some
 types of performance tuning can be done by configuring the underlying
 databases. See the <A HREF="../../../com/sleepycat/persist/EntityStore.html" title="class in com.sleepycat.persist"><CODE>EntityStore</CODE></A> class for more information on
 database and sequence configuration.

If you wish to access an index using the <code>Base API</code>, you may call
 the <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html#getDatabase()"><CODE>PrimaryIndex.getDatabase()</CODE></A> or <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getDatabase()"><CODE>SecondaryIndex.getDatabase()</CODE></A>
 method to get the underlying database. To translate between entity or key
 objects and <A HREF="../../../com/sleepycat/db/DatabaseEntry.html" title="class in com.sleepycat.db"><CODE>DatabaseEntry</CODE></A> objects at this level, use the bindings
 returned by <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html#getEntityBinding()"><CODE>PrimaryIndex.getEntityBinding()</CODE></A>, <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html#getKeyBinding()"><CODE>PrimaryIndex.getKeyBinding()</CODE></A>, and <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getKeyBinding()"><CODE>SecondaryIndex.getKeyBinding()</CODE></A>.

<HR>

<A NAME="method_summary"></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="2">
Method Summary</TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;boolean</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#contains(K)">contains</A>(<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Checks for existence of a key in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;boolean</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#contains(com.sleepycat.db.Transaction, K, com.sleepycat.db.LockMode)">contains</A>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key,
 <A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db">LockMode</A>&nbsp;lockMode)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns a non-transactional count of the entities in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;boolean</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(K)">delete</A>(<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Deletes all entities with a given index key.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;boolean</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(com.sleepycat.db.Transaction, K)">delete</A>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Deletes all entities with a given index key.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities()">entities</A>()</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Opens a cursor for traversing all entities in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(K, boolean, K, boolean)">entities</A>(<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;toKey,
 boolean&nbsp;toInclusive)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Opens a cursor for traversing entities in a key range.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)">entities</A>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A>&nbsp;config)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Opens a cursor for traversing all entities in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(com.sleepycat.db.Transaction, K, boolean, K, boolean, com.sleepycat.db.CursorConfig)">entities</A>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;toKey,
 boolean&nbsp;toInclusive,
 <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A>&nbsp;config)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Gets an entity via a key of this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A></CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#get(com.sleepycat.db.Transaction, K, com.sleepycat.db.LockMode)">get</A>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key,
 <A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db">LockMode</A>&nbsp;lockMode)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Opens a cursor for traversing all keys in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(K, boolean, K, boolean)">keys</A>(<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;toKey,
 boolean&nbsp;toInclusive)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Opens a cursor for traversing keys in a key range.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)">keys</A>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A>&nbsp;config)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Opens a cursor for traversing all keys in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(com.sleepycat.db.Transaction, K, boolean, K, boolean, com.sleepycat.db.CursorConfig)">keys</A>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;toKey,
 boolean&nbsp;toInclusive,
 <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A>&nbsp;config)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Opens a cursor for traversing keys in a key range.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/util/Map.html" title="class or interface in java.util">Map</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>,<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#map()">map</A>()</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns a standard Java map based on this entity index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/util/SortedMap.html" title="class or interface in java.util">SortedMap</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>,<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#sortedMap()">sortedMap</A>()</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns a standard Java sorted map based on this entity index.</TD>
</TR>
</TABLE>
&nbsp;

<A NAME="method_detail"></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="1">
Method Detail</TH>
</TR>
</TABLE>

<A NAME="contains(java.lang.Object)"></A><A NAME="contains(K)"></A><H3>
contains</H3>
<PRE>
boolean contains(<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Checks for existence of a key in this index.

The operation will not be transaction protected, and <A HREF="../../../com/sleepycat/db/LockMode.html#DEFAULT"><CODE>LockMode.DEFAULT</CODE></A> is used implicitly.

<DD><DL>
<DT>Parameters:<DD><CODE>key</CODE> - the key to search for.
<DT>Returns:<DD>whether the key exists in the index.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="contains(com.sleepycat.db.Transaction,java.lang.Object,com.sleepycat.db.LockMode)"></A><A NAME="contains(com.sleepycat.db.Transaction, K, com.sleepycat.db.LockMode)"></A><H3>
contains</H3>
<PRE>
boolean contains(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key,
 <A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db">LockMode</A>&nbsp;lockMode)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Checks for existence of a key in this index.

<DD><DL>
<DT>Parameters:<DD><CODE>txn</CODE> - the transaction used to protect this operation, or null
 if the operation should not be transaction protected.<DD><CODE>key</CODE> - the key to search for.<DD><CODE>lockMode</CODE> - the lock mode to use for this operation, or null to
 use <A HREF="../../../com/sleepycat/db/LockMode.html#DEFAULT"><CODE>LockMode.DEFAULT</CODE></A>.
<DT>Returns:<DD>whether the key exists in the index.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="get(java.lang.Object)"></A><A NAME="get(K)"></A><H3>
get</H3>
<PRE>
<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A> get(<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Gets an entity via a key of this index.

The operation will not be transaction protected, and <A HREF="../../../com/sleepycat/db/LockMode.html#DEFAULT"><CODE>LockMode.DEFAULT</CODE></A> is used implicitly.

<DD><DL>
<DT>Parameters:<DD><CODE>key</CODE> - the key to search for.
<DT>Returns:<DD>the value mapped to the given key, or null if the key is not
 present in the index.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="get(com.sleepycat.db.Transaction,java.lang.Object,com.sleepycat.db.LockMode)"></A><A NAME="get(com.sleepycat.db.Transaction, K, com.sleepycat.db.LockMode)"></A><H3>
get</H3>
<PRE>
<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A> get(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key,
 <A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db">LockMode</A>&nbsp;lockMode)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Gets an entity via a key of this index.

<DD><DL>
<DT>Parameters:<DD><CODE>txn</CODE> - the transaction used to protect this operation, or null
 if the operation should not be transaction protected.<DD><CODE>key</CODE> - the key to search for.<DD><CODE>lockMode</CODE> - the lock mode to use for this operation, or null to
 use <A HREF="../../../com/sleepycat/db/LockMode.html#DEFAULT"><CODE>LockMode.DEFAULT</CODE></A>.
<DT>Returns:<DD>the value mapped to the given key, or null if the key is not
 present in the index.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="count()"></A><H3>
count</H3>
<PRE>
long count()
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Returns a non-transactional count of the entities in this index.

This operation is faster than obtaining a count by scanning the index
 manually, and will not perturb the current contents of the cache.
 However, the count is not guaranteed to be accurate if there are
 concurrent updates.

<DD><DL>

<DT>Returns:<DD>the number of entities in this index.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="delete(java.lang.Object)"></A><A NAME="delete(K)"></A><H3>
delete</H3>
<PRE>
boolean delete(<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Deletes all entities with a given index key.

Auto-commit is used implicitly if the store is transactional.

<DD><DL>
<DT>Parameters:<DD><CODE>key</CODE> - the key to search for.
<DT>Returns:<DD>whether any entities were deleted.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="delete(com.sleepycat.db.Transaction,java.lang.Object)"></A><A NAME="delete(com.sleepycat.db.Transaction, K)"></A><H3>
delete</H3>
<PRE>
boolean delete(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;key)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Deletes all entities with a given index key.

<DD><DL>
<DT>Parameters:<DD><CODE>txn</CODE> - the transaction used to protect this operation, null to use
 auto-commit, or null if the store is non-transactional.<DD><CODE>key</CODE> - the key to search for.
<DT>Returns:<DD>whether any entities were deleted.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="keys()"></A><H3>
keys</H3>
<PRE>
<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&gt; keys()
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Opens a cursor for traversing all keys in this index.

<DT>Returns:<DD>the cursor.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="keys(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)"></A><H3>
keys</H3>
<PRE>
<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&gt; keys(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A>&nbsp;config)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Opens a cursor for traversing all keys in this index.

<DD><DL>
<DT>Parameters:<DD><CODE>txn</CODE> - the transaction used to protect all operations performed with
 the cursor, or null if the operations should not be transaction
 protected. If null is specified and the store is transactional, the
 cursor may not be used to update or delete entities.<DD><CODE>config</CODE> - the cursor configuration that determines the default lock
 mode used for all cursor operations, or null to implicitly use <A HREF="../../../com/sleepycat/db/CursorConfig.html#DEFAULT"><CODE>CursorConfig.DEFAULT</CODE></A>.
<DT>Returns:<DD>the cursor.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="entities()"></A><H3>
entities</H3>
<PRE>
<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt; entities()
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Opens a cursor for traversing all entities in this index.

<A NAME="entities(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)"></A><H3>
entities</H3>
<PRE>
<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt; entities(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A>&nbsp;config)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Opens a cursor for traversing all entities in this index.

<DD><DL>
<DT>Parameters:<DD><CODE>txn</CODE> - the transaction used to protect all operations performed with
 the cursor, or null if the operations should not be transaction
 protected. If null is specified and the store is transactional, the
 cursor may not be used to update or delete entities.<DD><CODE>config</CODE> - the cursor configuration that determines the default lock
 mode used for all cursor operations, or null to implicitly use <A HREF="../../../com/sleepycat/db/CursorConfig.html#DEFAULT"><CODE>CursorConfig.DEFAULT</CODE></A>.
<DT>Returns:<DD>the cursor.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="keys(java.lang.Object,boolean,java.lang.Object,boolean)"></A><A NAME="keys(K, boolean, K, boolean)"></A><H3>
keys</H3>
<PRE>
<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&gt; keys(<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;toKey,
 boolean&nbsp;toInclusive)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Opens a cursor for traversing keys in a key range.

The operations performed with the cursor will not be transaction
 protected, and <A HREF="../../../com/sleepycat/db/CursorConfig.html#DEFAULT"><CODE>CursorConfig.DEFAULT</CODE></A> is used implicitly. If the
 store is transactional, the cursor may not be used to update or delete
 entities.

<DD><DL>
<DT>Parameters:<DD><CODE>fromKey</CODE> - is the lower bound of the key range, or null if the range
 has no lower bound.<DD><CODE>fromInclusive</CODE> - is true if keys greater than or equal to fromKey
 should be included in the key range, or false if only keys greater than
 fromKey should be included.<DD><CODE>toKey</CODE> - is the upper bound of the key range, or null if the range
 has no upper bound.<DD><CODE>toInclusive</CODE> - is true if keys less than or equal to toKey should be
 included in the key range, or false if only keys less than toKey should
 be included.
<DT>Returns:<DD>the cursor.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="keys(com.sleepycat.db.Transaction,java.lang.Object,boolean,java.lang.Object,boolean,com.sleepycat.db.CursorConfig)"></A><A NAME="keys(com.sleepycat.db.Transaction, K, boolean, K, boolean, com.sleepycat.db.CursorConfig)"></A><H3>
keys</H3>
<PRE>
<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&gt; keys(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;toKey,
 boolean&nbsp;toInclusive,
 <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A>&nbsp;config)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Opens a cursor for traversing keys in a key range.

<DD><DL>
<DT>Parameters:<DD><CODE>txn</CODE> - the transaction used to protect all operations performed with
 the cursor, or null if the operations should not be transaction
 protected. If null is specified and the store is transactional, the
 cursor may not be used to update or delete entities.<DD><CODE>fromKey</CODE> - is the lower bound of the key range, or null if the range
 has no lower bound.<DD><CODE>fromInclusive</CODE> - is true if keys greater than or equal to fromKey
 should be included in the key range, or false if only keys greater than
 fromKey should be included.<DD><CODE>toKey</CODE> - is the upper bound of the key range, or null if the range
 has no upper bound.<DD><CODE>toInclusive</CODE> - is true if keys less than or equal to toKey should be
 included in the key range, or false if only keys less than toKey should
 be included.<DD><CODE>config</CODE> - the cursor configuration that determines the default lock
 mode used for all cursor operations, or null to implicitly use <A HREF="../../../com/sleepycat/db/CursorConfig.html#DEFAULT"><CODE>CursorConfig.DEFAULT</CODE></A>.
<DT>Returns:<DD>the cursor.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="entities(java.lang.Object,boolean,java.lang.Object,boolean)"></A><A NAME="entities(K, boolean, K, boolean)"></A><H3>
entities</H3>
<PRE>
<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt; entities(<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;toKey,
 boolean&nbsp;toInclusive)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Opens a cursor for traversing entities in a key range.

<A NAME="entities(com.sleepycat.db.Transaction,java.lang.Object,boolean,java.lang.Object,boolean,com.sleepycat.db.CursorConfig)"></A><A NAME="entities(com.sleepycat.db.Transaction, K, boolean, K, boolean, com.sleepycat.db.CursorConfig)"></A><H3>
entities</H3>
<PRE>
<A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt; entities(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>&nbsp;toKey,
 boolean&nbsp;toInclusive,
 <A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A>&nbsp;config)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Opens a cursor for traversing entities in a key range.

<DD><DL>
<DT>Parameters:<DD><CODE>txn</CODE> - the transaction used to protect all operations performed with
 the cursor, or null if the operations should not be transaction
 protected. If null is specified and the store is transactional, the
 cursor may not be used to update or delete entities.<DD><CODE>fromKey</CODE> - is the lower bound of the key range, or null if the range
 has no lower bound.<DD><CODE>fromInclusive</CODE> - is true if keys greater than or equal to fromKey
 should be included in the key range, or false if only keys greater than
 fromKey should be included.<DD><CODE>toKey</CODE> - is the upper bound of the key range, or null if the range
 has no upper bound.<DD><CODE>toInclusive</CODE> - is true if keys less than or equal to toKey should be
 included in the key range, or false if only keys less than toKey should
 be included.<DD><CODE>config</CODE> - the cursor configuration that determines the default lock
 mode used for all cursor operations, or null to implicitly use <A HREF="../../../com/sleepycat/db/CursorConfig.html#DEFAULT"><CODE>CursorConfig.DEFAULT</CODE></A>.
<DT>Returns:<DD>the cursor.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DD>
</DL>
<HR>

<A NAME="map()"></A><H3>
map</H3>
<PRE>
<A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/util/Map.html" title="class or interface in java.util">Map</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>,<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt; map()</PRE>
<DL>
<DD>Returns a standard Java map based on this entity index. The <A HREF="../../../com/sleepycat/collections/StoredMap.html" title="class in com.sleepycat.collections"><CODE>StoredMap</CODE></A> returned is defined by the <A HREF="../../../com/sleepycat/collections/package-summary.html">Collections API</A>. Stored collections conform
 to the standard Java collections framework interface.

<DD><DL>

<DT>Returns:<DD>the map.</DL>
</DD>
</DL>
<HR>

<A NAME="sortedMap()"></A><H3>
sortedMap</H3>
<PRE>
<A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/util/SortedMap.html" title="class or interface in java.util">SortedMap</A>&lt;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">K</A>,<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="type parameter in EntityIndex">V</A>&gt; sortedMap()</PRE>
<DL>
<DD>Returns a standard Java sorted map based on this entity index. The
 <A HREF="../../../com/sleepycat/collections/StoredSortedMap.html" title="class in com.sleepycat.collections"><CODE>StoredSortedMap</CODE></A> returned is defined by the <A HREF="../../../com/sleepycat/collections/package-summary.html">Collections API</A>. Stored collections conform
 to the standard Java collections framework interface.

<DD><DL>

<DT>Returns:<DD>the map.</DL>
</DD>
</DL>

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