javax.jdo.identity

Class ObjectIdentity

java.lang.Object

javax.jdo.identity.SingleFieldIdentity

javax.jdo.identity.ObjectIdentity

All Implemented Interfaces:

Externalizable, Serializable, Comparable

public class ObjectIdentity
extends SingleFieldIdentity

This class is for identity with a single Object type field.

Version:

2.0

See Also:

Serialized Form

Field Summary

Fields inherited from class javax.jdo.identity.SingleFieldIdentity

hashCode, keyAsObject, msg

Constructor Summary

Constructors

Constructor and Description
ObjectIdentity() Constructor only for Externalizable.
ObjectIdentity(Class pcClass, Object param) Constructor with class and key.

Method Summary

Methods

Modifier and Type	Method and Description
int	compareTo(Object o) Determine the ordering of identity objects.
boolean	equals(Object obj) Determine if the other object represents the same object id.
Object	getKey() Return the key.
int	hashCode() Provide the hash code for this instance.
void	readExternal(ObjectInput in) Read this object.
String	toString() Return the String form of the object id.
void	writeExternal(ObjectOutput out) Write this object.

Methods inherited from class javax.jdo.identity.SingleFieldIdentity

assertKeyNotNull, compare, createKeyAsObject, getKeyAsObject, getTargetClass, getTargetClassName, hashClassName, setKeyAsObject

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ObjectIdentity

public ObjectIdentity(Class pcClass,
              Object param)

Constructor with class and key.

Parameters:

pcClass - the class

param - the key

ObjectIdentity

public ObjectIdentity()

Constructor only for Externalizable.

Method Detail

getKey

public Object getKey()

Return the key.

Returns:

the key

toString

public String toString()

Return the String form of the object id. The class of the object id is written as the first part of the result so that the class can be reconstructed later. Then the toString of the key instance is appended. During construction, this process is reversed. The class is extracted from the first part of the String, and the String constructor of the key is used to construct the key itself.

Overrides:

toString in class Object

Returns:

the String form of the key

equals

public boolean equals(Object obj)

Determine if the other object represents the same object id.

Overrides:

equals in class SingleFieldIdentity

Parameters:

obj - the other object

Returns:

true if both objects represent the same object id

hashCode

public int hashCode()

Provide the hash code for this instance. The hash code is the hash code of the contained key.

Overrides:

hashCode in class SingleFieldIdentity

Returns:

the hash code

compareTo

public int compareTo(Object o)

Determine the ordering of identity objects.

Parameters:

o - Other identity

Returns:

The relative ordering between the objects

Since:

2.2

writeExternal

public void writeExternal(ObjectOutput out)
                   throws IOException

Write this object. Write the superclass first.

Specified by:

writeExternal in interface Externalizable

Overrides:

writeExternal in class SingleFieldIdentity

Parameters:

out - the output

Throws:

IOException

readExternal

public void readExternal(ObjectInput in)
                  throws IOException,
                         ClassNotFoundException

Read this object. Read the superclass first.

Specified by:

readExternal in interface Externalizable

Overrides:

readExternal in class SingleFieldIdentity

Parameters:

in - the input

Throws:

IOException

ClassNotFoundException