230 words

javax.jdo.identity.SingleFieldIdentity - JDO class

javax.jdo.identity
Class SingleFieldIdentity

java.lang.Object
    javax.jdo.identity.SingleFieldIdentity
Implemented Interfaces:
Externalizable, Serializable, Comparable
Subclasses:
ByteIdentity, CharIdentity, IntIdentity, LongIdentity, ObjectIdentity, ShortIdentity, StringIdentity
This class is the abstract base class for all single field identity classes. A common case of application identity uses exactly one persistent field in the class to represent identity. In this case, the application can use a standard JDO class instead of creating a new user-defined class for the purpose.
Since:
JDO 1.0
Constructor only for Externalizable.
Constructor only for Externalizable.
Since:
JDO 2.0
int compareTo(T arg0)
Parameters:
arg0 -
boolean equals(Object obj)
Check the class and class name and object type.
Check the class and class name and object type. If restored from serialization, class will be null so compare class name.
Parameters:
obj - the other object
Returns:
true if the class or class name is the same
Since:
JDO 1.0
Return the key as an Object.
Return the key as an Object. The method is synchronized to avoid race conditions in multi-threaded environments.
Returns:
the key as an Object.
Since:
JDO 2.0
Return the target class.
Return the target class.
Returns:
the target class.
Since:
JDO 2.0
Return the target class name.
Return the target class name.
Returns:
the target class name.
Since:
JDO 2.0
int hashCode()
Return the cached hash code.
Return the cached hash code.
Returns:
the cached hash code.
Since:
JDO 1.0
void readExternal(ObjectInput arg0)throws IOException, ClassNotFoundException
Parameters:
arg0 -
void readExternal(ObjectInput in)throws IOException, ClassNotFoundException
Read from the input stream.
Read from the input stream. Creates a new instance with the target class name set
Parameters:
in -
Since:
JDO 1.0
void writeExternal(ObjectOutput arg0)
Parameters:
arg0 -
void writeExternal(ObjectOutput out)
Write to the output stream.
Write to the output stream.
Parameters:
out - the stream
Since:
JDO 1.0

This documentation page is derived (with some adjustments) from the JDO 2.2 API
and is available under the terms of the Apache License, v. 2.0.