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<H2>

com.sleepycat.persist
 
Class SecondaryIndex&lt;SK,PK,E&gt;</H2>
<PRE>
<A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html" title="class or interface in java.lang">java.lang.Object</A>
 <IMG SRC="../../../resources/inherit.gif" ALT="extended by ">com.sleepycat.persist.SecondaryIndex&lt;SK,PK,E&gt;
</PRE>
<DL>
<DT>All Implemented Interfaces: <DD><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;SK,E&gt;</DD>
</DL>
<HR>
<DL>
<DT><PRE>public class SecondaryIndex&lt;SK,PK,E&gt;<DT>extends <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A></DL>
</PRE>

The secondary index for an entity class and a secondary key.

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

<code>SecondaryIndex</code> implements <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist"><CODE>EntityIndex</CODE></A> to map the
 secondary key type (SK) to the entity type (E). In other words, entities
 are accessed by secondary key values.

The <A HREF="../../../com/sleepycat/persist/model/SecondaryKey.html" title="annotation in com.sleepycat.persist.model"><CODE>SecondaryKey</CODE></A> annotation may be used to define a secondary key
 as shown in the following example.

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

@PrimaryKey
     long id;

@SecondaryKey(relate=MANY_TO_ONE)
     String department;

String name;

private Employee() {}
 }</pre>

Before obtaining a <code>SecondaryIndex</code>, the <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist"><CODE>PrimaryIndex</CODE></A> must
 be obtained for the entity class. To obtain the <code>SecondaryIndex</code> call
 <A HREF="../../../com/sleepycat/persist/EntityStore.html#getSecondaryIndex(com.sleepycat.persist.PrimaryIndex, java.lang.Class, java.lang.String)"><CODE>EntityStore.getSecondaryIndex</CODE></A>, passing
 the primary index, the secondary key class and the secondary key name. For
 example:

<pre class="code">
 EntityStore store = new EntityStore(...);

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

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

Since <code>SecondaryIndex</code> implements the <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist"><CODE>EntityIndex</CODE></A>
 interface, it shares the common index methods for retrieving and deleting
 entities, opening cursors and using transactions. See <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist"><CODE>EntityIndex</CODE></A>
 for more information on these topics.

<code>SecondaryIndex</code> does not provide methods for inserting
 and updating entities. That must be done using the <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist"><CODE>PrimaryIndex</CODE></A>.

Note that a <code>SecondaryIndex</code> has three type parameters <code>&lt;SK,PK,E&gt;</code> or in the example <code>&lt;String,Long,Employee&gt;</code> while a <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist"><CODE>PrimaryIndex</CODE></A> has only two type parameters <code>&lt;PK,E&gt;</code> or <code>&lt;Long,Employee&gt;</code>. This is because a <code>SecondaryIndex</code> has an extra
 level of mapping: It maps from secondary key to primary key, and then from
 primary key to entity. For example, consider this entity:

<table class="code" border="1">
 <tr><th>ID</th><th>Department</th><th>Name</th></tr>
 <tr><td>1</td><td>Engineering</td><td>Jane Smith</td></tr>
 </table>

The <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist"><CODE>PrimaryIndex</CODE></A> maps from id directly to the entity, or from
 primary key 1 to the "Jane Smith" entity in the example. The <code>SecondaryIndex</code> maps from department to id, or from secondary key
 "Engineering" to primary key 1 in the example, and then uses the <code>PrimaryIndex</code> to map from the primary key to the entity.

Because of this extra type parameter and extra level of mapping, a <code>SecondaryIndex</code> can provide more than one mapping, or view, of the entities
 in the primary index. The main mapping of a <code>SecondaryIndex</code> is to
 map from secondary key (SK) to entity (E), or in the example, from the
 String department key to the Employee entity. The <code>SecondaryIndex</code>
 itself, by implementing <code>EntityIndex&lt;SK,E&gt;</code>, provides this
 mapping.

The second mapping provided by <code>SecondaryIndex</code> is from secondary
 key (SK) to primary key (PK), or in the example, from the String department
 key to the Long id key. The <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex"><CODE>keysIndex</CODE></A> method provides this
 mapping. When accessing the keys index, the primary key is returned rather
 than the entity. When only the primary key is needed and not the entire
 entity, using the keys index is less expensive than using the secondary
 index because the primary index does not have to be accessed.

The third mapping provided by <code>SecondaryIndex</code> is from primary key
 (PK) to entity (E), for the subset of entities having a given secondary key
 (SK). This mapping is provided by the <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#subIndex(SK)"><CODE>subIndex(SK)</CODE></A> method. A
 sub-index is convenient when you are interested in working with the subset
 of entities having a particular secondary key value, for example, all
 employees in a given department.

All three mappings, along with the mapping provided by the <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist"><CODE>PrimaryIndex</CODE></A>, are shown using example data in the <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist"><CODE>EntityIndex</CODE></A>
 interface documentation. See <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist"><CODE>EntityIndex</CODE></A> for more information.

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>One-to-One Relationships</h3>

A <A HREF="../../../com/sleepycat/persist/model/Relationship.html#ONE_TO_ONE"><CODE>ONE_TO_ONE</CODE></A> relationship, although less
 common than other types of relationships, is the simplest type of
 relationship. A single entity is related to a single secondary key value.
 For example:

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

@PrimaryKey
     long id;

@SecondaryKey(relate=ONE_TO_ONE)
     String ssn;

String name;

private Employee() {}
 }

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

With a <A HREF="../../../com/sleepycat/persist/model/Relationship.html#ONE_TO_ONE"><CODE>ONE_TO_ONE</CODE></A> relationship, the
 secondary key must be unique; in other words, no two entities may have the
 same secondary key value. If an attempt is made to store an entity having
 the same secondary key value as another existing entity, a <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db"><CODE>DatabaseException</CODE></A> will be thrown.

Because the secondary key is unique, it is useful to lookup entities by
 secondary key using <A HREF="../../../com/sleepycat/persist/EntityIndex.html#get(K)"><CODE>EntityIndex.get(K)</CODE></A>. For example:

<pre class="code">
 Employee employee = employeeBySsn.get(mySsn);</pre>

<h3>Many-to-One Relationships</h3>

A <A HREF="../../../com/sleepycat/persist/model/Relationship.html#MANY_TO_ONE"><CODE>MANY_TO_ONE</CODE></A> relationship is the most
 common type of relationship. One or more entities is related to a single
 secondary key value. For example:

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

@PrimaryKey
     long id;

@SecondaryKey(relate=MANY_TO_ONE)
     String department;

String name;

private Employee() {}
 }

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

With a <A HREF="../../../com/sleepycat/persist/model/Relationship.html#MANY_TO_ONE"><CODE>MANY_TO_ONE</CODE></A> relationship, the
 secondary key is not required to be unique; in other words, more than one
 entity may have the same secondary key value. In this example, more than
 one employee may belong to the same department.

The most convenient way to access the employees in a given department is
 by using a sub-index. For example:

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

<h3>One-to-Many Relationships</h3>

In a <A HREF="../../../com/sleepycat/persist/model/Relationship.html#ONE_TO_MANY"><CODE>ONE_TO_MANY</CODE></A> relationship, a single
 entity is related to one or more secondary key values. For example:

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

@PrimaryKey
     long id;

@SecondaryKey(relate=ONE_TO_MANY)
     Set&lt;String&gt; emailAddresses = new HashSet&lt;String&gt;;

String name;

private Employee() {}
 }

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

With a <A HREF="../../../com/sleepycat/persist/model/Relationship.html#ONE_TO_MANY"><CODE>ONE_TO_MANY</CODE></A> relationship, the
 secondary key must be unique; in other words, no two entities may have the
 same secondary key value. In this example, no two employees may have the
 same email address. If an attempt is made to store an entity having the
 same secondary key value as another existing entity, a <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db"><CODE>DatabaseException</CODE></A> will be thrown.

<pre class="code">
 Employee employee = employeeByEmail.get(myEmailAddress);</pre>

The secondary key field for a <A HREF="../../../com/sleepycat/persist/model/Relationship.html#ONE_TO_MANY"><CODE>ONE_TO_MANY</CODE></A> relationship must be an array or collection type. To access
 the email addresses of an employee, simply access the collection field
 directly. For example:

<pre class="code">
 Employee employee = primaryIndex.get(1); // Get the entity by primary key
 employee.emailAddresses.add(myNewEmail); // Add an email address
 primaryIndex.putNoReturn(1, employee); // Update the entity</pre>

<h3>Many-to-Many Relationships</h3>

In a <A HREF="../../../com/sleepycat/persist/model/Relationship.html#MANY_TO_MANY"><CODE>MANY_TO_MANY</CODE></A> relationship, one
 or more entities is related to one or more secondary key values. For
 example:

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

@PrimaryKey
     long id;

@SecondaryKey(relate=MANY_TO_MANY)
     Set&lt;String&gt; organizations = new HashSet&lt;String&gt;;

String name;

private Employee() {}
 }

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

With a <A HREF="../../../com/sleepycat/persist/model/Relationship.html#MANY_TO_MANY"><CODE>MANY_TO_MANY</CODE></A> relationship, the
 secondary key is not required to be unique; in other words, more than one
 entity may have the same secondary key value. In this example, more than
 one employee may belong to the same organization.

The most convenient way to access the employees in a given organization
 is by using a sub-index. For example:

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

The secondary key field for a <A HREF="../../../com/sleepycat/persist/model/Relationship.html#MANY_TO_MANY"><CODE>MANY_TO_MANY</CODE></A> relationship must be an array or collection type. To access
 the organizations of an employee, simply access the collection field
 directly. For example:

<pre class="code">
 Employee employee = primaryIndex.get(1); // Get the entity by primary key
 employee.organizations.remove(myOldOrg); // Remove an organization
 primaryIndex.putNoReturn(1, employee); // Update the entity</pre>

<h3>Foreign Key Constraints for Related Entities</h3>

In all the examples above the secondary key is treated only as a simple
 value, such as a <code>String</code> department field. In many cases, that is
 sufficient. But in other cases, you may wish to constrain the secondary
 keys of one entity class to be valid primary keys of another entity
 class. For example, a Department entity may also be defined:

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

@PrimaryKey
     String name;

String missionStatement;

private Department() {}
 }</pre>

You may wish to constrain the department field values of the Employee
 class in the examples above to be valid primary keys of the Department
 entity class. In other words, you may wish to ensure that the department
 field of an Employee will always refer to a valid Department entity.

You can implement this constraint yourself by validating the department
 field before you store an Employee. For example:

<pre class="code">
 <code>PrimaryIndex&lt;String,Department&gt;</code> departmentIndex =
 store.getPrimaryIndex(String.class, Department.class);

void storeEmployee(Employee employee) throws DatabaseException {
 if (departmentIndex.contains(employee.department)) {
 primaryIndex.putNoReturn(employee);
 } else {
 throw new IllegalArgumentException("Department does not exist: " +
 employee.department);
 }
 }</pre>

Or, instead you could define the Employee department field as a foreign
 key, and this validation will be done for you when you attempt to store the
 Employee entity. For example:

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

@PrimaryKey
     long id;

@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Department.class)
     String department;

String name;

private Employee() {}
 }</pre>

The <code>relatedEntity=Department.class</code> above defines the department
 field as a foreign key that refers to a Department entity. Whenever a
 Employee entity is stored, its department field value will be checked to
 ensure that a Department entity exists with that value as its primary key.
 If no such Department entity exists, then a <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db"><CODE>DatabaseException</CODE></A> is
 thrown, causing the transaction to be aborted (assuming that transactions
 are used).

This begs the question: What happens when a Department entity is deleted
 while one or more Employee entities have department fields that refer to
 the deleted department's primary key? If the department were allowed to be
 deleted, the foreign key constraint for the Employee department field would
 be violated, because the Employee department field would refer to a
 department that does not exist.

By default, when this situation arises the system does not allow the
 department to be deleted. Instead, a <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db"><CODE>DatabaseException</CODE></A> is thrown,
 causing the transaction to be aborted. In this case, in order to delete a
 department, the department field of all Employee entities must first be
 updated to refer to a different existing department, or set to null. This
 is the responsibility of the application.

There are two additional ways of handling deletion of a Department
 entity. These alternatives are configured using the <A HREF="../../../com/sleepycat/persist/model/SecondaryKey.html#onRelatedEntityDelete()"><CODE>SecondaryKey.onRelatedEntityDelete()</CODE></A> annotation property. Setting this
 property to <A HREF="../../../com/sleepycat/persist/model/DeleteAction.html#NULLIFY"><CODE>DeleteAction.NULLIFY</CODE></A> causes the Employee department
 field to be automatically set to null when the department they refer to is
 deleted. This may or may not be desirable, depending on application
 policies. For example:

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

@PrimaryKey
     long id;

<code>@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Department.class,
 onRelatedEntityDelete=NULLIFY)</code>
 String department;

String name;

private Employee() {}
 }</pre>

The <A HREF="../../../com/sleepycat/persist/model/DeleteAction.html#CASCADE"><CODE>DeleteAction.CASCADE</CODE></A> value, on the other hand, causes the
 Employee entities to be automatically deleted when the department they refer
 to is deleted. This is probably not desirable in this particular example,
 but is useful for parent-child relationships. For example:

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

@PrimaryKey
     long id;

String description;

private Order() {}
 }

@Entity
 class OrderItem {

@PrimaryKey
     long id;

<code>@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Order.class,
 onRelatedEntityDelete=CASCADE)</code>
 long orderId;

String description;

private OrderItem() {}
 }</pre>

The OrderItem orderId field refers to its "parent" Order entity. When an
 Order entity is deleted, it may be useful to automatically delete its
 "child" OrderItem entities.

For more information, see <A HREF="../../../com/sleepycat/persist/model/SecondaryKey.html#onRelatedEntityDelete()"><CODE>SecondaryKey.onRelatedEntityDelete()</CODE></A>.

<h3>One-to-Many versus Many-to-One for Related Entities</h3>

When there is a conceptual Many-to-One relationship such as Employee to
 Department as illustrated in the examples above, the relationship may be
 implemented either as Many-to-One in the Employee class or as One-to-Many in
 the Department class.

Here is the Many-to-One approach.

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

@PrimaryKey
     long id;

@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Department.class)
     String department;

String name;

private Employee() {}
 }

@Entity
 class Department {

@PrimaryKey
     String name;

String missionStatement;

private Department() {}
 }</pre>

And here is the One-to-Many approach.

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

@PrimaryKey
     long id;

String name;

private Employee() {}
 }

@Entity
 class Department {

@PrimaryKey
     String name;

String missionStatement;

@SecondaryKey(relate=ONE_TO_MANY, relatedEntity=Employee.class)
     Set&lt;Long&gt; employees = new HashSet&lt;Long&gt;;

private Department() {}
 }</pre>

Which approach is best? The Many-to-One approach better handles large
 number of entities on the to-Many side of the relationship because it
 doesn't store a collection of keys as an entity field. With Many-to-One a
 Btree is used to store the collection of keys and the Btree can easily
 handle very large numbers of keys. With One-to-Many, each time a related
 key is added or removed the entity on the One side of the relationship,
 along with the complete collection of related keys, must be updated.
 Therefore, if large numbers of keys may be stored per relationship,
 Many-to-One is recommended.

If the number of entities per relationship is not a concern, then you may
 wish to choose the approach that is most natural in your application data
 model. For example, if you think of a Department as containing employees
 and you wish to modify the Department object each time an employee is added
 or removed, then you may wish to store a collection of Employee keys in the
 Department object (One-to-Many).

Note that if you have a One-to-Many relationship and there is no related
 entity, then you don't have a choice -- you have to use One-to-Many because
 there is no entity on the to-Many side of the relationship where a
 Many-to-One key could be defined. An example is the Employee to email
 addresses relationship discussed above:

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

@PrimaryKey
     long id;

@SecondaryKey(relate=ONE_TO_MANY)
     Set&lt;String&gt; emailAddresses = new HashSet&lt;String&gt;;

String name;

private Employee() {}
 }</pre>

For sake of argument imagine that each employee has thousands of email
 addresses and employees frequently add and remove email addresses. To
 avoid the potential performance problems associated with updating the
 Employee entity every time an email address is added or removed, you could
 create an EmployeeEmailAddress entity and use a Many-to-One relationship as
 shown below:

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

@PrimaryKey
     long id;

String name;

private Employee() {}
 }

@Entity
 class EmployeeEmailAddress {

@PrimaryKey
     String emailAddress;

@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Employee.class)
     long employeeId;

private EmployeeEmailAddress() {}
 }</pre>

<h3>Key Placement with Many-to-Many for Related Entities</h3>

As discussed in the section above, one drawback of a to-Many relationship
 (One-to-Many was discussed above and Many-to-Many is discussed here) is that
 it requires storing a collection of keys in an entity. Each time a key is
 added or removed, the containing entity must be updated. This has potential
 performance problems when there are large numbers of entities on the to-Many
 side of the relationship, in other words, when there are large numbers of
 keys in each secondary key field collection.

If you have a Many-to-Many relationship with a reasonably small number of
 entities on one side of the relationship and a large number of entities on
 the other side, you can avoid the potential performance problems by defining
 the secondary key field on the side with a small number of entities.

For example, in an Employee-to-Organization relationship, the number of
 organizations per employee will normally be reasonably small but the number
 of employees per organization may be very large. Therefore, to avoid
 potential performance problems, the secondary key field should be defined in
 the Employee class as shown below.

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

@PrimaryKey
     long id;

@SecondaryKey(relate=MANY_TO_MANY, relatedEntity=Organization.class)
     Set&lt;String&gt; organizations = new HashSet&lt;String&gt;;

String name;

private Employee() {}
 }

@Entity
 class Organization {

@PrimaryKey
     String name;

String description;
 }</pre>

If instead a <code>Set&lt;Long&gt; members</code> key had been defined in the
 Organization class, this set could potentially have a large number of
 elements and performance problems could result.

<h3>Many-to-Many Versus a Relationship Entity</h3>

If you have a Many-to-Many relationship with a large number of entities
 on both sides of the relationship, you can avoid the potential
 performance problems by using a relationship entity. A
 relationship entity defines the relationship between two other entities
 using two Many-to-One relationships.

Imagine a relationship between cars and trucks indicating whenever a
 particular truck was passed on the road by a particular car. A given car
 may pass a large number of trucks and a given truck may be passed by a large
 number of cars. First look at a Many-to-Many relationship between these two
 entities:

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

@PrimaryKey
     String licenseNumber;

@SecondaryKey(relate=MANY_TO_MANY, relatedEntity=Truck.class)
     Set&lt;String&gt; trucksPassed = new HashSet&lt;String&gt;;

String color;

private Car() {}
 }

@Entity
 class Truck {

@PrimaryKey
     String licenseNumber;

int tons;

private Truck() {}
 }</pre>

With the Many-to-Many approach above, the <code>trucksPassed</code> set could
 potentially have a large number of elements and performance problems could
 result.

To apply the relationship entity approach we define a new entity class
 named CarPassedTruck representing a single truck passed by a single car. We
 remove the secondary key from the Car class and use two secondary keys in
 the CarPassedTruck class instead.

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

@PrimaryKey
     String licenseNumber;

String color;

private Car() {}
 }

@Entity
 class Truck {

@PrimaryKey
     String licenseNumber;

int tons;

private Truck() {}
 }

@Entity
 class CarPassedTruck {

@PrimaryKey
     long id;

@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Car.class)
     String carLicense;

@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Truck.class)
     String truckLicense;

private CarPassedTruck() {}
 }</pre>

The CarPassedTruck entity can be used to access the relationship by car
 license or by truck license.

You may use the relationship entity approach because of the potential
 performance problems mentioned above. Or, you may choose to use this
 approach in order to store other information about the relationship. For
 example, if for each car that passes a truck you wish to record how much
 faster the car was going than the truck, then a relationship entity is the
 logical place to store that property. In the example below the
 speedDifference property is added to the CarPassedTruck class.

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

@PrimaryKey
     long id;

@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Car.class)
     String carLicense;

@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Truck.class)
     String truckLicense;

int speedDifference;

private CarPassedTruck() {}
 }</pre>

Be aware that the relationship entity approach adds overhead compared to
 Many-to-Many. There is one additional entity and one additional secondary
 key. These factors should be weighed against its advantages and the
 relevant application access patterns should be considered.

<HR>

<A NAME="constructor_summary"></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TH ALIGN="left" COLSPAN="2">
Constructor Summary</TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#SecondaryIndex(com.sleepycat.db.SecondaryDatabase, com.sleepycat.db.Database, com.sleepycat.persist.PrimaryIndex, java.lang.Class, com.sleepycat.bind.EntryBinding)">SecondaryIndex</A>(<A HREF="../../../com/sleepycat/db/SecondaryDatabase.html" title="class in com.sleepycat.db">SecondaryDatabase</A>&nbsp;database,
 <A HREF="../../../com/sleepycat/db/Database.html" title="class in com.sleepycat.db">Database</A>&nbsp;keysDatabase,
 <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist">PrimaryIndex</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">PK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A>&gt;&nbsp;primaryIndex,
 <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Class.html" title="class or interface in java.lang">Class</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>&gt;&nbsp;secondaryKeyClass,
 <A HREF="../../../com/sleepycat/bind/EntryBinding.html" title="interface in com.sleepycat.bind">EntryBinding</A>&nbsp;secondaryKeyBinding)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Creates a secondary index without using an <code>EntityStore</code>.</TD>
</TR>
</TABLE>
&nbsp;

<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/SecondaryIndex.html#contains(K)">contains</A>(K&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/SecondaryIndex.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,
 K&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/SecondaryIndex.html#delete(K)">delete</A>(K&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/SecondaryIndex.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,
 K&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;E&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#entities()">entities</A>()</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;E&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.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;E&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.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,
 K&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 K&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 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/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A></CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#get(SK)">get</A>(<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>&nbsp;key)</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/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A></CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#get(com.sleepycat.db.Transaction, SK, 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/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</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 the underlying secondary database for this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/bind/EntryBinding.html" title="interface in com.sleepycat.bind">EntryBinding</A></CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getKeyBinding()">getKeyBinding</A>()</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns the secondary key binding for the 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/lang/Class.html" title="class or interface in java.lang">Class</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getKeyClass()">getKeyClass</A>()</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns the secondary key class for this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/db/Database.html" title="class in com.sleepycat.db">Database</A></CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getKeysDatabase()">getKeysDatabase</A>()</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns the underlying secondary database that is not associated with
 the primary database and is used for the <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex"><CODE>keysIndex</CODE></A>.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist">PrimaryIndex</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">PK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getPrimaryIndex()">getPrimaryIndex</A>()</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns the primary index associated with this secondary 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;K&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keys()">keys</A>()</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;K&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.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;K&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.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,
 K&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 K&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="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">PK</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex()">keysIndex</A>()</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns a read-only keys index that maps secondary key to primary key.</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/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.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/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.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>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%">
<CODE>&nbsp;<A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">PK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A>&gt;</CODE></TD>
<TD><CODE><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#subIndex(SK)">subIndex</A>(<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>&nbsp;key)</CODE>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns an index that maps primary key to entity for the subset of
 entities having a given secondary key (duplicates).</TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_java.lang.Object"></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TH ALIGN="left">Methods inherited from class java.lang.<A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#clone()" title="class or interface in java.lang">clone</A>, <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#equals(java.lang.Object)" title="class or interface in java.lang">equals</A>, <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#finalize()" title="class or interface in java.lang">finalize</A>, <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#getClass()" title="class or interface in java.lang">getClass</A>, <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#hashCode()" title="class or interface in java.lang">hashCode</A>, <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#notify()" title="class or interface in java.lang">notify</A>, <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#notifyAll()" title="class or interface in java.lang">notifyAll</A>, <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#toString()" title="class or interface in java.lang">toString</A>, <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#wait()" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#wait(long)" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html#wait(long, int)" title="class or interface in java.lang">wait</A></CODE></TD>
</TR>
</TABLE>
&nbsp;

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

<A NAME="SecondaryIndex(com.sleepycat.db.SecondaryDatabase, com.sleepycat.db.Database, com.sleepycat.persist.PrimaryIndex, java.lang.Class, com.sleepycat.bind.EntryBinding)"></A><H3>
SecondaryIndex</H3>
<PRE>
public SecondaryIndex(<A HREF="../../../com/sleepycat/db/SecondaryDatabase.html" title="class in com.sleepycat.db">SecondaryDatabase</A>&nbsp;database,
 <A HREF="../../../com/sleepycat/db/Database.html" title="class in com.sleepycat.db">Database</A>&nbsp;keysDatabase,
 <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist">PrimaryIndex</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">PK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A>&gt;&nbsp;primaryIndex,
 <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Class.html" title="class or interface in java.lang">Class</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>&gt;&nbsp;secondaryKeyClass,
 <A HREF="../../../com/sleepycat/bind/EntryBinding.html" title="interface in com.sleepycat.bind">EntryBinding</A>&nbsp;secondaryKeyBinding)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Creates a secondary index without using an <code>EntityStore</code>.
 When using an <A HREF="../../../com/sleepycat/persist/EntityStore.html" title="class in com.sleepycat.persist"><CODE>EntityStore</CODE></A>, call <A HREF="../../../com/sleepycat/persist/EntityStore.html#getSecondaryIndex(com.sleepycat.persist.PrimaryIndex, java.lang.Class, java.lang.String)"><CODE>getSecondaryIndex</CODE></A> instead.

This constructor is not normally needed and is provided for
 applications that wish to use custom bindings along with the Direct
 Persistence Layer. Normally, <A HREF="../../../com/sleepycat/persist/EntityStore.html#getSecondaryIndex(com.sleepycat.persist.PrimaryIndex, java.lang.Class, java.lang.String)"><CODE>getSecondaryIndex</CODE></A> is used instead.

<DL>
<DT>Parameters:<DD><CODE>database</CODE> - the secondary database used for all access other than
 via a <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex"><CODE>keysIndex</CODE></A>.<DD><CODE>keysDatabase</CODE> - another handle on the secondary database, opened
 without association to the primary, and used only for access via a
 <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex"><CODE>keysIndex</CODE></A>. If this argument is null and the <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex"><CODE>keysIndex</CODE></A>
 method is called, then the keys database will be opened automatically;
 however, the user is then responsible for closing the keys database. To
 get the keys database in order to close it, call <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getKeysDatabase()"><CODE>getKeysDatabase()</CODE></A>.<DD><CODE>primaryIndex</CODE> - the primary index associated with this secondary
 index.<DD><CODE>secondaryKeyClass</CODE> - the class of the secondary key.<DD><CODE>secondaryKeyBinding</CODE> - the binding to be used for secondary keys.
<DT>Throws:
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DL>

<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="getDatabase()"></A><H3>
getDatabase</H3>
<PRE>
public <A HREF="../../../com/sleepycat/db/SecondaryDatabase.html" title="class in com.sleepycat.db">SecondaryDatabase</A> getDatabase()</PRE>
<DL>
<DD>Returns the underlying secondary database for this index.

<DD><DL>

<DT>Returns:<DD>the secondary database.</DL>
</DD>
</DL>
<HR>

<A NAME="getKeysDatabase()"></A><H3>
getKeysDatabase</H3>
<PRE>
public <A HREF="../../../com/sleepycat/db/Database.html" title="class in com.sleepycat.db">Database</A> getKeysDatabase()</PRE>
<DL>
<DD>Returns the underlying secondary database that is not associated with
 the primary database and is used for the <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex"><CODE>keysIndex</CODE></A>.

<DD><DL>

<DT>Returns:<DD>the keys database.</DL>
</DD>
</DL>
<HR>

<A NAME="getPrimaryIndex()"></A><H3>
getPrimaryIndex</H3>
<PRE>
public <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist">PrimaryIndex</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">PK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A>&gt; getPrimaryIndex()</PRE>
<DL>
<DD>Returns the primary index associated with this secondary index.

<DD><DL>

<DT>Returns:<DD>the primary index.</DL>
</DD>
</DL>
<HR>

<A NAME="getKeyClass()"></A><H3>
getKeyClass</H3>
<PRE>
public <A HREF="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Class.html" title="class or interface in java.lang">Class</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>&gt; getKeyClass()</PRE>
<DL>
<DD>Returns the secondary key class for this index.

<DD><DL>

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

<A NAME="getKeyBinding()"></A><H3>
getKeyBinding</H3>
<PRE>
public <A HREF="../../../com/sleepycat/bind/EntryBinding.html" title="interface in com.sleepycat.bind">EntryBinding</A> getKeyBinding()</PRE>
<DL>
<DD>Returns the secondary key binding for the index.

<DD><DL>

<DT>Returns:<DD>the key binding.</DL>
</DD>
</DL>
<HR>

<A NAME="keysIndex()"></A><H3>
keysIndex</H3>
<PRE>
public <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">PK</A>&gt; keysIndex()
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Returns a read-only keys index that maps secondary key to primary key.
 When accessing the keys index, the primary key is returned rather than
 the entity. When only the primary key is needed and not the entire
 entity, using the keys index is less expensive than using the secondary
 index because the primary index does not have to be accessed.

Note the following in the unusual case that you are not
 using an <code>EntityStore</code>: This method will open the keys
 database, a second database handle for the secondary database, if it is
 not already open. In this case, if you are not using an
 <code>EntityStore</code>, then you are responsible for closing the
 database returned by <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getKeysDatabase()"><CODE>getKeysDatabase()</CODE></A> before closing the
 environment. If you are using an <code>EntityStore</code>, the
 keys database will be closed automatically by <A HREF="../../../com/sleepycat/persist/EntityStore.html#close()"><CODE>EntityStore.close()</CODE></A>.

<DD><DL>

<DT>Returns:<DD>the keys 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="subIndex(java.lang.Object)"></A><A NAME="subIndex(SK)"></A><H3>
subIndex</H3>
<PRE>
public <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">PK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A>&gt; subIndex(<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>&nbsp;key)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Returns an index that maps primary key to entity for the subset of
 entities having a given secondary key (duplicates). A sub-index is
 convenient when you are interested in working with the subset of
 entities having a particular secondary key value.

When using a <A HREF="../../../com/sleepycat/persist/model/Relationship.html#MANY_TO_ONE"><CODE>MANY_TO_ONE</CODE></A> or <A HREF="../../../com/sleepycat/persist/model/Relationship.html#MANY_TO_MANY"><CODE>MANY_TO_MANY</CODE></A> secondary key, the sub-index
 represents the left (MANY) side of a relationship.

<DD><DL>
<DT>Parameters:<DD><CODE>key</CODE> - the secondary key that identifies the entities in the
 sub-index.
<DT>Returns:<DD>the sub-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(SK)"></A><H3>
get</H3>
<PRE>
public <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A> get(<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>&nbsp;key)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#get(K)">EntityIndex</A></CODE></DD>
<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, SK, com.sleepycat.db.LockMode)"></A><H3>
get</H3>
<PRE>
public <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A> get(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</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>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#get(com.sleepycat.db.Transaction, K, com.sleepycat.db.LockMode)">EntityIndex</A></CODE></DD>
<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="map()"></A><H3>
map</H3>
<PRE>
public <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/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A>&gt; map()</PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#map()">EntityIndex</A></CODE></DD>
<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>
public <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/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>,<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A>&gt; sortedMap()</PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#sortedMap()">EntityIndex</A></CODE></DD>
<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>
<HR>

<A NAME="contains(java.lang.Object)"></A><A NAME="contains(K)"></A><H3>
contains</H3>
<PRE>
public boolean contains(K&nbsp;key)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#contains(K)">EntityIndex</A></CODE></DD>
<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>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#contains(K)">contains</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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>
public boolean contains(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 K&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>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#contains(com.sleepycat.db.Transaction, K, com.sleepycat.db.LockMode)">EntityIndex</A></CODE></DD>
<DD>Checks for existence of a key in this index.

<DD><DL>
<DT>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#contains(com.sleepycat.db.Transaction, K, com.sleepycat.db.LockMode)">contains</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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="count()"></A><H3>
count</H3>
<PRE>
public long count()
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#count()">EntityIndex</A></CODE></DD>
<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>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#count()">count</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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>
public boolean delete(K&nbsp;key)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(K)">EntityIndex</A></CODE></DD>
<DD>Deletes all entities with a given index key.

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

<DD><DL>
<DT>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(K)">delete</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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>
public boolean delete(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 K&nbsp;key)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(com.sleepycat.db.Transaction, K)">EntityIndex</A></CODE></DD>
<DD>Deletes all entities with a given index key.

<DD><DL>
<DT>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(com.sleepycat.db.Transaction, K)">delete</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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>
public <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;K&gt; keys()
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys()">EntityIndex</A></CODE></DD>
<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>
public <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;K&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>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)">EntityIndex</A></CODE></DD>
<DD>Opens a cursor for traversing all keys in this index.

<DD><DL>
<DT>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)">keys</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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>
public <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;E&gt; entities()
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities()">EntityIndex</A></CODE></DD>
<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>
public <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;E&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>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)">EntityIndex</A></CODE></DD>
<DD>Opens a cursor for traversing all entities in this index.

<DD><DL>
<DT>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)">entities</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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>
public <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;K&gt; keys(K&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 K&nbsp;toKey,
 boolean&nbsp;toInclusive)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(K, boolean, K, boolean)">EntityIndex</A></CODE></DD>
<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>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(K, boolean, K, boolean)">keys</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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>
public <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;K&gt; keys(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 K&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 K&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>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(com.sleepycat.db.Transaction, K, boolean, K, boolean, com.sleepycat.db.CursorConfig)">EntityIndex</A></CODE></DD>
<DD>Opens a cursor for traversing keys in a key range.

<DD><DL>
<DT>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(com.sleepycat.db.Transaction, K, boolean, K, boolean, com.sleepycat.db.CursorConfig)">keys</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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>
public <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;E&gt; entities(K&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 K&nbsp;toKey,
 boolean&nbsp;toInclusive)
 throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(K, boolean, K, boolean)">EntityIndex</A></CODE></DD>
<DD>Opens a cursor for traversing entities 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>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(K, boolean, K, boolean)">entities</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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="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>
public <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A>&lt;E&gt; entities(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A>&nbsp;txn,
 K&nbsp;fromKey,
 boolean&nbsp;fromInclusive,
 K&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>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(com.sleepycat.db.Transaction, K, boolean, K, boolean, com.sleepycat.db.CursorConfig)">EntityIndex</A></CODE></DD>
<DD>Opens a cursor for traversing entities in a key range.

<DD><DL>
<DT>Specified by:<DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(com.sleepycat.db.Transaction, K, boolean, K, boolean, com.sleepycat.db.CursorConfig)">entities</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A>&lt;K,E&gt;</CODE></DL>
</DD>
<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>

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