com.kabira.platform

Class KeyManager<T>

java.lang.Object

com.kabira.platform.KeyManager<T>

public class KeyManager<T>
extends java.lang.Object

Factory for KeyQuery instances.

Constructor Summary

Constructors

Constructor and Description
KeyManager() Creates a KeyManager instance.

Method Summary

Modifier and Type	Method and Description
KeyQuery<T>	createKeyQuery(java.lang.Class<T> klass, java.lang.String keyName) Returns a new instance of a KeyQuery class.
KeyQuery<T>	createKeyQuery(java.lang.String className, java.lang.String keyName) Returns a new instance of a KeyQuery class.
static byte[]	getKeyData(java.lang.Object obj, java.lang.String keyName) Access the key data for the given object and key.
static void	updateIndexes(java.lang.Object obj) Update the key indexes for the given object.

Methods inherited from class java.lang.Object

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

Constructor Detail

KeyManager

public KeyManager()

Creates a KeyManager instance.

Method Detail

createKeyQuery

public KeyQuery<T> createKeyQuery(java.lang.Class<T> klass,
                                  java.lang.String keyName)
                           throws KeyUnknownKeyNameError

Returns a new instance of a KeyQuery class.

Parameters:

klass - Class containing the key.

keyName - Name defining the key.

Returns:

KeyQuery instance.

Throws:

KeyUnknownKeyNameError - The given keyName is not defined for the type.

createKeyQuery

public KeyQuery<T> createKeyQuery(java.lang.String className,
                                  java.lang.String keyName)
                           throws KeyUnknownKeyNameError

Returns a new instance of a KeyQuery class.

Parameters:

className - Class name containing the key.

keyName - Name defining the key.

Returns:

KeyQuery instance.

Throws:

KeyUnknownKeyNameError - The given keyName is not defined for the type.

updateIndexes

public static void updateIndexes(java.lang.Object obj)
                          throws ObjectNotUniqueError,
                                 ManagedClassError

Update the key indexes for the given object.

This method must be called after any mutable key fields have been updated to insure the key indexes reflects the field values. If the Managed object has no keys, or no key fields have been modified, this method quietly does nothing.

If mutable key fields are updated, and this method is not called, a fatal exception is thrown by the runtime at commit time.

This method does not need to be executed in a constructor, key field changes made in constructors are automatically applied to key indexes when the constructor finishes execution.

Parameters:

obj - Object containing the modified key fields.

Throws:

ObjectNotUniqueError - The updated fields would result in a duplicate instance.

ManagedClassError - if object is not Managed.

getKeyData

public static byte[] getKeyData(java.lang.Object obj,
                                java.lang.String keyName)
                         throws ManagedClassError,
                                KeyUnknownKeyNameError

Access the key data for the given object and key.

This method returns a byte array containing the key data stored in the fields that comprise a key for the object. This byte array can be used to compute a hash value for the instance by key value.

Parameters:

obj - Object containing the key fields.

keyName - Name defining the key.

Returns:

Byte array containing key data.

Throws:

ManagedClassError - The object is not Managed.

KeyUnknownKeyNameError - The given keyName is not defined for the object class.