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<H2>
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com.sleepycat.persist</FONT>
<BR>
Class SecondaryIndex<SK,PK,E></H2>
<PRE>
java.lang.Object
<IMG SRC="../../../resources/inherit.gif" ALT="extended by "><B>com.sleepycat.persist.SecondaryIndex<SK,PK,E></B>
</PRE>
<DL>
<DT><B>All Implemented Interfaces:</B> <DD><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A><SK,E></DD>
</DL>
<HR>
<DL>
<DT><PRE>public class <B>SecondaryIndex<SK,PK,E></B><DT>extends java.lang.Object</DL>
</PRE>
<P>
The secondary index for an entity class and a secondary key.
<p><code>SecondaryIndex</code> objects are thread-safe. Multiple threads may
safely call the methods of a shared <code>SecondaryIndex</code> object.</p>
<p><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.</p>
<p>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.</p>
<pre class="code">
@Entity
class Employee {
@PrimaryKey
long id;
@SecondaryKey(relate=MANY_TO_ONE)
String department;
String name;
private Employee() {}
}</pre>
<p>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:</p>
<pre class="code">
EntityStore store = new EntityStore(...);
<code>PrimaryIndex<Long,Employee></code> primaryIndex =
store.getPrimaryIndex(Long.class, Employee.class);
<code>SecondaryIndex<String,Long,Employee></code> secondaryIndex =
store.getSecondaryIndex(primaryIndex, String.class, "department");</pre>
<p>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.</p>
<p><code>SecondaryIndex</code> does <em>not</em> 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>.</p>
<p>Note that a <code>SecondaryIndex</code> has three type parameters <code><SK,PK,E></code> or in the example <code><String,Long,Employee></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><PK,E></code> or <code><Long,Employee></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:</p>
<p><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></p>
<p>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.</p>
<p>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<SK,E></code>, provides this
mapping.</p>
<p>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.</p>
<p>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.</p>
<p>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.</p>
<p>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.</p>
<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>
<p>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:</p>
<pre class="code">
@Entity
class Employee {
@PrimaryKey
long id;
@SecondaryKey(relate=ONE_TO_ONE)
String ssn;
String name;
private Employee() {}
}
<code>SecondaryIndex<String,Long,Employee></code> employeeBySsn =
store.getSecondaryIndex(primaryIndex, String.class, "ssn");</pre>
<p>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.</p>
<p>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:</p>
<pre class="code">
Employee employee = employeeBySsn.get(mySsn);</pre>
<h3>Many-to-One Relationships</h3>
<p>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:</p>
<pre class="code">
@Entity
class Employee {
@PrimaryKey
long id;
@SecondaryKey(relate=MANY_TO_ONE)
String department;
String name;
private Employee() {}
}
<code>SecondaryIndex<String,Long,Employee></code> employeeByDepartment =
store.getSecondaryIndex(primaryIndex, String.class, "department");</pre>
<p>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.</p>
<p>The most convenient way to access the employees in a given department is
by using a sub-index. For example:</p>
<pre class="code">
<code>EntityIndex<Long,Entity></code> subIndex = employeeByDepartment.subIndex(myDept);
<code>EntityCursor<Employee></code> cursor = subIndex.entities();
try {
for (Employee entity : cursor) {
// Do something with the entity...
}
} finally {
cursor.close();
}</pre>
<h3>One-to-Many Relationships</h3>
<p>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:</p>
<pre class="code">
@Entity
class Employee {
@PrimaryKey
long id;
@SecondaryKey(relate=ONE_TO_MANY)
Set<String> emailAddresses = new HashSet<String>;
String name;
private Employee() {}
}
<code>SecondaryIndex<String,Long,Employee></code> employeeByEmail =
store.getSecondaryIndex(primaryIndex, String.class, "emailAddresses");</pre>
<p>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.</p>
<p>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:</p>
<pre class="code">
Employee employee = employeeByEmail.get(myEmailAddress);</pre>
<p>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:</p>
<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>
<p>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:</p>
<pre class="code">
@Entity
class Employee {
@PrimaryKey
long id;
@SecondaryKey(relate=MANY_TO_MANY)
Set<String> organizations = new HashSet<String>;
String name;
private Employee() {}
}
<code>SecondaryIndex<String,Long,Employee></code> employeeByOrganization =
store.getSecondaryIndex(primaryIndex, String.class, "organizations");</pre>
<p>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.</p>
<p>The most convenient way to access the employees in a given organization
is by using a sub-index. For example:</p>
<pre class="code">
<code>EntityIndex<Long,Entity></code> subIndex = employeeByOrganization.subIndex(myOrg);
<code>EntityCursor<Employee></code> cursor = subIndex.entities();
try {
for (Employee entity : cursor) {
// Do something with the entity...
}
} finally {
cursor.close();
}</pre>
<p>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:</p>
<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>
<p>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:</p>
<pre class="code">
@Entity
class Department {
@PrimaryKey
String name;
String missionStatement;
private Department() {}
}</pre>
<p>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.</p>
<p>You can implement this constraint yourself by validating the department
field before you store an Employee. For example:</p>
<pre class="code">
<code>PrimaryIndex<String,Department></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>
<p>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:</p>
<pre class="code">
@Entity
class Employee {
@PrimaryKey
long id;
@SecondaryKey(relate=MANY_TO_ONE, relatedEntity=Department.class)
String department;
String name;
private Employee() {}
}</pre>
<p>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).</p>
<p>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.</p>
<p>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.</p>
<p>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:</p>
<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>
<p>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:</p>
<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>
<p>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.</p>
<p>For more information, see <A HREF="../../../com/sleepycat/persist/model/SecondaryKey.html#onRelatedEntityDelete()"><CODE>SecondaryKey.onRelatedEntityDelete()</CODE></A>.</p>
<h3>One-to-Many versus Many-to-One for Related Entities</h3>
<p>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.</p>
<p>Here is the Many-to-One approach.</p>
<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>
<p>And here is the One-to-Many approach.</p>
<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<Long> employees = new HashSet<Long>;
private Department() {}
}</pre>
<p>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.</p>
<p>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).</p>
<p>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:</p>
<pre class="code">
@Entity
class Employee {
@PrimaryKey
long id;
@SecondaryKey(relate=ONE_TO_MANY)
Set<String> emailAddresses = new HashSet<String>;
String name;
private Employee() {}
}</pre>
<p>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:</p>
<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>
<p>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.</p>
<p>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.</p>
<p>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.</p>
<pre class="code">
@Entity
class Employee {
@PrimaryKey
long id;
@SecondaryKey(relate=MANY_TO_MANY, relatedEntity=Organization.class)
Set<String> organizations = new HashSet<String>;
String name;
private Employee() {}
}
@Entity
class Organization {
@PrimaryKey
String name;
String description;
}</pre>
<p>If instead a <code>Set<Long> 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.</p>
<h3>Many-to-Many Versus a Relationship Entity</h3>
<p>If you have a Many-to-Many relationship with a large number of entities
on <em>both</em> sides of the relationship, you can avoid the potential
performance problems by using a <em>relationship entity</em>. A
relationship entity defines the relationship between two other entities
using two Many-to-One relationships.</p>
<p>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:</p>
<pre class="code">
@Entity
class Car {
@PrimaryKey
String licenseNumber;
@SecondaryKey(relate=MANY_TO_MANY, relatedEntity=Truck.class)
Set<String> trucksPassed = new HashSet<String>;
String color;
private Car() {}
}
@Entity
class Truck {
@PrimaryKey
String licenseNumber;
int tons;
private Truck() {}
}</pre>
<p>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.</p>
<p>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.</p>
<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>
<p>The CarPassedTruck entity can be used to access the relationship by car
license or by truck license.</p>
<p>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.</p>
<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>
<p>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.</p>
<P>
<P>
<HR>
<P>
<!-- ======== CONSTRUCTOR SUMMARY ======== -->
<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"><FONT SIZE="+2">
<B>Constructor Summary</B></FONT></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><B><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></B>(<A HREF="../../../com/sleepycat/db/SecondaryDatabase.html" title="class in com.sleepycat.db">SecondaryDatabase</A> database,
<A HREF="../../../com/sleepycat/db/Database.html" title="class in com.sleepycat.db">Database</A> keysDatabase,
<A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist">PrimaryIndex</A><<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>> primaryIndex,
java.lang.Class<<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>> secondaryKeyClass,
<A HREF="../../../com/sleepycat/bind/EntryBinding.html" title="interface in com.sleepycat.bind">EntryBinding</A> secondaryKeyBinding)</CODE>
<BR>
Creates a secondary index without using an <code>EntityStore</code>.</TD>
</TR>
</TABLE>
<!-- ========== METHOD SUMMARY =========== -->
<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"><FONT SIZE="+2">
<B>Method Summary</B></FONT></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#contains(K)">contains</A></B>(K key)</CODE>
<BR>
Checks for existence of a key in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#contains(com.sleepycat.db.Transaction, K, com.sleepycat.db.LockMode)">contains</A></B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
K key,
<A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db">LockMode</A> lockMode)</CODE>
<BR>
Checks for existence of a key in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> long</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#count()">count</A></B>()</CODE>
<BR>
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%"><FONT SIZE="-1">
<CODE> boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#delete(K)">delete</A></B>(K key)</CODE>
<BR>
Deletes all entities with a given index key.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#delete(com.sleepycat.db.Transaction, K)">delete</A></B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
K key)</CODE>
<BR>
Deletes all entities with a given index key.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A><E></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#entities()">entities</A></B>()</CODE>
<BR>
Opens a cursor for traversing all entities in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A><E></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#entities(K, boolean, K, boolean)">entities</A></B>(K fromKey,
boolean fromInclusive,
K toKey,
boolean toInclusive)</CODE>
<BR>
Opens a cursor for traversing entities in a key range.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A><E></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#entities(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)">entities</A></B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
<A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A> config)</CODE>
<BR>
Opens a cursor for traversing all entities in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A><E></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#entities(com.sleepycat.db.Transaction, K, boolean, K, boolean, com.sleepycat.db.CursorConfig)">entities</A></B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
K fromKey,
boolean fromInclusive,
K toKey,
boolean toInclusive,
<A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A> config)</CODE>
<BR>
Opens a cursor for traversing entities in a key range.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#get(SK)">get</A></B>(<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A> key)</CODE>
<BR>
Gets an entity via a key of this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">E</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#get(com.sleepycat.db.Transaction, SK, com.sleepycat.db.LockMode)">get</A></B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A> key,
<A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db">LockMode</A> lockMode)</CODE>
<BR>
Gets an entity via a key of this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/db/SecondaryDatabase.html" title="class in com.sleepycat.db">SecondaryDatabase</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getDatabase()">getDatabase</A></B>()</CODE>
<BR>
Returns the underlying secondary database for this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/bind/EntryBinding.html" title="interface in com.sleepycat.bind">EntryBinding</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getKeyBinding()">getKeyBinding</A></B>()</CODE>
<BR>
Returns the secondary key binding for the index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> java.lang.Class<<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getKeyClass()">getKeyClass</A></B>()</CODE>
<BR>
Returns the secondary key class for this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/db/Database.html" title="class in com.sleepycat.db">Database</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getKeysDatabase()">getKeysDatabase</A></B>()</CODE>
<BR>
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%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist">PrimaryIndex</A><<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>></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#getPrimaryIndex()">getPrimaryIndex</A></B>()</CODE>
<BR>
Returns the primary index associated with this secondary index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A><K></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keys()">keys</A></B>()</CODE>
<BR>
Opens a cursor for traversing all keys in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A><K></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keys(K, boolean, K, boolean)">keys</A></B>(K fromKey,
boolean fromInclusive,
K toKey,
boolean toInclusive)</CODE>
<BR>
Opens a cursor for traversing keys in a key range.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A><K></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keys(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)">keys</A></B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
<A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A> config)</CODE>
<BR>
Opens a cursor for traversing all keys in this index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/EntityCursor.html" title="interface in com.sleepycat.persist">EntityCursor</A><K></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keys(com.sleepycat.db.Transaction, K, boolean, K, boolean, com.sleepycat.db.CursorConfig)">keys</A></B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
K fromKey,
boolean fromInclusive,
K toKey,
boolean toInclusive,
<A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A> config)</CODE>
<BR>
Opens a cursor for traversing keys in a key range.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A><<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>></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#keysIndex()">keysIndex</A></B>()</CODE>
<BR>
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%"><FONT SIZE="-1">
<CODE> java.util.Map<<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>></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#map()">map</A></B>()</CODE>
<BR>
Returns a standard Java map based on this entity index.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE> java.util.SortedMap<<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>></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#sortedMap()">sortedMap</A></B>()</CODE>
<BR>
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%"><FONT SIZE="-1">
<CODE> <A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A><<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>></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../com/sleepycat/persist/SecondaryIndex.html#subIndex(SK)">subIndex</A></B>(<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A> key)</CODE>
<BR>
Returns an index that maps primary key to entity for the subset of
entities having a given secondary key (duplicates).</TD>
</TR>
</TABLE>
<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"><B>Methods inherited from class java.lang.Object</B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE>clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait</CODE></TD>
</TR>
</TABLE>
<P>
<!-- ========= CONSTRUCTOR DETAIL ======== -->
<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"><FONT SIZE="+2">
<B>Constructor Detail</B></FONT></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 <B>SecondaryIndex</B>(<A HREF="../../../com/sleepycat/db/SecondaryDatabase.html" title="class in com.sleepycat.db">SecondaryDatabase</A> database,
<A HREF="../../../com/sleepycat/db/Database.html" title="class in com.sleepycat.db">Database</A> keysDatabase,
<A HREF="../../../com/sleepycat/persist/PrimaryIndex.html" title="class in com.sleepycat.persist">PrimaryIndex</A><<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>> primaryIndex,
java.lang.Class<<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>> secondaryKeyClass,
<A HREF="../../../com/sleepycat/bind/EntryBinding.html" title="interface in com.sleepycat.bind">EntryBinding</A> 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.
<p>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.</p>
<P>
<DL>
<DT><B>Parameters:</B><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><B>Throws:</B>
<DD><CODE><A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></CODE></DL>
</DL>
<!-- ============ METHOD DETAIL ========== -->
<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"><FONT SIZE="+2">
<B>Method Detail</B></FONT></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> <B>getDatabase</B>()</PRE>
<DL>
<DD>Returns the underlying secondary database for this index.
<P>
<DD><DL>
<DT><B>Returns:</B><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> <B>getKeysDatabase</B>()</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>.
<P>
<DD><DL>
<DT><B>Returns:</B><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><<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>> <B>getPrimaryIndex</B>()</PRE>
<DL>
<DD>Returns the primary index associated with this secondary index.
<P>
<DD><DL>
<DT><B>Returns:</B><DD>the primary index.</DL>
</DD>
</DL>
<HR>
<A NAME="getKeyClass()"><!-- --></A><H3>
getKeyClass</H3>
<PRE>
public java.lang.Class<<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A>> <B>getKeyClass</B>()</PRE>
<DL>
<DD>Returns the secondary key class for this index.
<P>
<DD><DL>
<DT><B>Returns:</B><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> <B>getKeyBinding</B>()</PRE>
<DL>
<DD>Returns the secondary key binding for the index.
<P>
<DD><DL>
<DT><B>Returns:</B><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><<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>> <B>keysIndex</B>()
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.
<p>Note the following in the unusual case that you are <em>not</em>
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 <em>not</em> 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 <em>are</em> 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>.</p>
<P>
<DD><DL>
<DT><B>Returns:</B><DD>the keys index.
<DT><B>Throws:</B>
<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><<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>> <B>subIndex</B>(<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A> 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.
<p>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.</p>
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>key</CODE> - the secondary key that identifies the entities in the
sub-index.
<DT><B>Returns:</B><DD>the sub-index.
<DT><B>Throws:</B>
<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> <B>get</B>(<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A> key)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#get(K)">EntityIndex</A></CODE></B></DD>
<DD>Gets an entity via a key of this index.
<p>The operation will not be transaction protected, and <A HREF="../../../com/sleepycat/db/LockMode.html#DEFAULT"><CODE>LockMode.DEFAULT</CODE></A> is used implicitly.</p>
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>key</CODE> - the key to search for.
<DT><B>Returns:</B><DD>the value mapped to the given key, or null if the key is not
present in the index.
<DT><B>Throws:</B>
<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> <B>get</B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
<A HREF="../../../com/sleepycat/persist/SecondaryIndex.html" title="type parameter in SecondaryIndex">SK</A> key,
<A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db">LockMode</A> lockMode)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>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></B></DD>
<DD>Gets an entity via a key of this index.
<P>
<DD><DL>
<DT><B>Parameters:</B><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><B>Returns:</B><DD>the value mapped to the given key, or null if the key is not
present in the index.
<DT><B>Throws:</B>
<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 java.util.Map<<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>> <B>map</B>()</PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#map()">EntityIndex</A></CODE></B></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 Collections API. Stored collections conform
to the standard Java collections framework interface.
<P>
<DD><DL>
<DT><B>Returns:</B><DD>the map.</DL>
</DD>
</DL>
<HR>
<A NAME="sortedMap()"><!-- --></A><H3>
sortedMap</H3>
<PRE>
public java.util.SortedMap<<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>> <B>sortedMap</B>()</PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#sortedMap()">EntityIndex</A></CODE></B></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 Collections API. Stored collections conform
to the standard Java collections framework interface.
<P>
<DD><DL>
<DT><B>Returns:</B><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 <B>contains</B>(K key)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#contains(K)">EntityIndex</A></CODE></B></DD>
<DD>Checks for existence of a key in this index.
<p>The operation will not be transaction protected, and <A HREF="../../../com/sleepycat/db/LockMode.html#DEFAULT"><CODE>LockMode.DEFAULT</CODE></A> is used implicitly.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>key</CODE> - the key to search for.
<DT><B>Returns:</B><DD>whether the key exists in the index.
<DT><B>Throws:</B>
<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 <B>contains</B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
K key,
<A HREF="../../../com/sleepycat/db/LockMode.html" title="class in com.sleepycat.db">LockMode</A> lockMode)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>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></B></DD>
<DD>Checks for existence of a key in this index.
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><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><B>Returns:</B><DD>whether the key exists in the index.
<DT><B>Throws:</B>
<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 <B>count</B>()
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#count()">EntityIndex</A></CODE></B></DD>
<DD>Returns a non-transactional count of the entities in this index.
<p>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.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Returns:</B><DD>the number of entities in this index.
<DT><B>Throws:</B>
<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 <B>delete</B>(K key)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(K)">EntityIndex</A></CODE></B></DD>
<DD>Deletes all entities with a given index key.
<p>Auto-commit is used implicitly if the store is transactional.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>key</CODE> - the key to search for.
<DT><B>Returns:</B><DD>whether any entities were deleted.
<DT><B>Throws:</B>
<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 <B>delete</B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
K key)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#delete(com.sleepycat.db.Transaction, K)">EntityIndex</A></CODE></B></DD>
<DD>Deletes all entities with a given index key.
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><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><B>Returns:</B><DD>whether any entities were deleted.
<DT><B>Throws:</B>
<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><K> <B>keys</B>()
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys()">EntityIndex</A></CODE></B></DD>
<DD>Opens a cursor for traversing all keys in this index.
<p>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.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys()">keys</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Returns:</B><DD>the cursor.
<DT><B>Throws:</B>
<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><K> <B>keys</B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
<A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A> config)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)">EntityIndex</A></CODE></B></DD>
<DD>Opens a cursor for traversing all keys in this index.
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><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><B>Returns:</B><DD>the cursor.
<DT><B>Throws:</B>
<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><E> <B>entities</B>()
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities()">EntityIndex</A></CODE></B></DD>
<DD>Opens a cursor for traversing all entities in this index.
<p>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.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities()">entities</A></CODE> in interface <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html" title="interface in com.sleepycat.persist">EntityIndex</A><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Returns:</B><DD>the cursor.
<DT><B>Throws:</B>
<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, 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><E> <B>entities</B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
<A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A> config)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(com.sleepycat.db.Transaction, com.sleepycat.db.CursorConfig)">EntityIndex</A></CODE></B></DD>
<DD>Opens a cursor for traversing all entities in this index.
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><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><B>Returns:</B><DD>the cursor.
<DT><B>Throws:</B>
<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><K> <B>keys</B>(K fromKey,
boolean fromInclusive,
K toKey,
boolean toInclusive)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#keys(K, boolean, K, boolean)">EntityIndex</A></CODE></B></DD>
<DD>Opens a cursor for traversing keys in a key range.
<p>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.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><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><B>Returns:</B><DD>the cursor.
<DT><B>Throws:</B>
<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><K> <B>keys</B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
K fromKey,
boolean fromInclusive,
K toKey,
boolean toInclusive,
<A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A> config)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>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></B></DD>
<DD>Opens a cursor for traversing keys in a key range.
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><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><B>Returns:</B><DD>the cursor.
<DT><B>Throws:</B>
<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><E> <B>entities</B>(K fromKey,
boolean fromInclusive,
K toKey,
boolean toInclusive)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>Description copied from interface: <CODE><A HREF="../../../com/sleepycat/persist/EntityIndex.html#entities(K, boolean, K, boolean)">EntityIndex</A></CODE></B></DD>
<DD>Opens a cursor for traversing entities in a key range.
<p>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.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><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><B>Returns:</B><DD>the cursor.
<DT><B>Throws:</B>
<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><E> <B>entities</B>(<A HREF="../../../com/sleepycat/db/Transaction.html" title="class in com.sleepycat.db">Transaction</A> txn,
K fromKey,
boolean fromInclusive,
K toKey,
boolean toInclusive,
<A HREF="../../../com/sleepycat/db/CursorConfig.html" title="class in com.sleepycat.db">CursorConfig</A> config)
throws <A HREF="../../../com/sleepycat/db/DatabaseException.html" title="class in com.sleepycat.db">DatabaseException</A></PRE>
<DL>
<DD><B>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></B></DD>
<DD>Opens a cursor for traversing entities in a key range.
<P>
<DD><DL>
<DT><B>Specified by:</B><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><K,E></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><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><B>Returns:</B><DD>the cursor.
<DT><B>Throws:</B>
<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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distrib
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