com.sleepycat.bind.serial
Class SerialSerialKeyCreator

java.lang.Object
  |
  +--com.sleepycat.bind.serial.SerialSerialKeyCreator

All Implemented Interfaces:

ForeignKeyNullifier, SecondaryKeyCreator

public abstract class SerialSerialKeyCreator

extends Object

implements SecondaryKeyCreator, ForeignKeyNullifier

A abstract key creator that uses a serial key and a serial data entry. This class takes care of serializing and deserializing the key and data entry automatically. The following abstract method must be implemented by a concrete subclass to create the index key using these objects

• createSecondaryKey(Object,Object)

If ForeignKeyDeleteAction.NULLIFY was specified when opening the secondary database, the following method must be overridden to nullify the foreign index key. If NULLIFY was not specified, this method need not be overridden.

• nullifyForeignKey(Object)

Author:

Mark Hayes

Constructor Summary

SerialSerialKeyCreator(ClassCatalog classCatalog, Class primaryKeyClass, Class dataClass, Class indexKeyClass)
Creates a serial-serial key creator.

SerialSerialKeyCreator(SerialBinding primaryKeyBinding, SerialBinding dataBinding, SerialBinding indexKeyBinding)
Creates a serial-serial entity binding.

Method Summary

abstract Object	createSecondaryKey(Object primaryKey, Object data) Creates the index key object from primary key and entry objects.
boolean	createSecondaryKey(SecondaryDatabase db, DatabaseEntry primaryKeyEntry, DatabaseEntry dataEntry, DatabaseEntry indexKeyEntry) Creates a secondary key entry, given a primary key and data entry.
Object	nullifyForeignKey(Object data) Clears the index key in a data object.
boolean	nullifyForeignKey(SecondaryDatabase db, DatabaseEntry dataEntry) Sets the foreign key reference to null in the datum of the primary database.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SerialSerialKeyCreator

public SerialSerialKeyCreator(ClassCatalog classCatalog,
                              Class primaryKeyClass,
                              Class dataClass,
                              Class indexKeyClass)

Creates a serial-serial key creator.

Parameters:

classCatalog - is the catalog to hold shared class information and for a database should be a StoredClassCatalog.

primaryKeyClass - is the primary key base class.

dataClass - is the data base class.

indexKeyClass - is the index key base class.

SerialSerialKeyCreator

public SerialSerialKeyCreator(SerialBinding primaryKeyBinding,
                              SerialBinding dataBinding,
                              SerialBinding indexKeyBinding)

Creates a serial-serial entity binding.

Parameters:

primaryKeyBinding - is the primary key binding.

dataBinding - is the data binding.

indexKeyBinding - is the index key binding.

Method Detail

createSecondaryKey

public boolean createSecondaryKey(SecondaryDatabase db,
                                  DatabaseEntry primaryKeyEntry,
                                  DatabaseEntry dataEntry,
                                  DatabaseEntry indexKeyEntry)
                           throws DatabaseException

Description copied from interface: SecondaryKeyCreator

Creates a secondary key entry, given a primary key and data entry.

Specified by:

createSecondaryKey in interface SecondaryKeyCreator

Parameters:

db - the database to which the secondary key will be added.

primaryKeyEntry - the primary key entry. This parameter must not be modified by this method.

dataEntry - the primary data entry. This parameter must not be modified by this method.

indexKeyEntry - the secondary key created by this method.

Returns:

true if a key was created, or false to indicate that the key is not present.

Throws:

DatabaseException - if an error occurs attempting to create the secondary key.

nullifyForeignKey

public boolean nullifyForeignKey(SecondaryDatabase db,
                                 DatabaseEntry dataEntry)
                          throws DatabaseException

Description copied from interface: ForeignKeyNullifier

Sets the foreign key reference to null in the datum of the primary database.

Specified by:

nullifyForeignKey in interface ForeignKeyNullifier

Parameters:

db - the database in which the foreign key integrity constraint is defined.

dataEntry - the existing primary key datum in which the foreign key reference should be set to null.

Returns:

true if the datum was modified, or false to indicate that the key is not present.

Throws:

DatabaseException - if an error occurs attempting to clear the key reference.

createSecondaryKey

public abstract Object createSecondaryKey(Object primaryKey,
                                          Object data)

Creates the index key object from primary key and entry objects.

Parameters:

primaryKey - is the deserialized source primary key entry, or null if no primary key entry is used to construct the index key.

data - is the deserialized source data entry, or null if no data entry is used to construct the index key.

Returns:

the destination index key object, or null to indicate that the key is not present.

nullifyForeignKey

public Object nullifyForeignKey(Object data)

Clears the index key in a data object.

On entry the data parameter contains the index key to be cleared. It should be changed by this method such that createSecondaryKey(com.sleepycat.je.SecondaryDatabase, com.sleepycat.je.DatabaseEntry, com.sleepycat.je.DatabaseEntry, com.sleepycat.je.DatabaseEntry) will return false. Other fields in the data object should remain unchanged.

Parameters:

data - is the source and destination data object.

Returns:

the destination data object, or null to indicate that the key is not present and no change is necessary. The data returned may be the same object passed as the data parameter or a newly created object.