org.jboss.ejb
Class CacheKey

java.lang.Object
  org.jboss.ejb.CacheKey

All Implemented Interfaces:

Externalizable, Serializable

Direct Known Subclasses:

FastKey, ListCacheKey

public class CacheKey

extends Object

implements Externalizable

CacheKey is an encapsulation of both the PrimaryKey and a cache specific key.

This implementation is a safe implementation in the sense that it doesn't rely on the user supplied hashcode and equals. It is also fast since the hashCode operation is pre-calculated.

Version:

$Revision: 1.21 $

Author:

Marc Fleury, Bill Burke, Scott Stark

See Also:

org.jboss.ejb.plugins.NoPassivationInstanceCache.java, EntityInstanceCache, org.jboss.ejb.plugins.EntityProxy, Serialized Form

Field Summary

protected int	hashCode The Marshalled Object's hashcode
protected Object	id The database primaryKey.
protected MarshalledObject	mo The Marshalled Object representing the key

Constructor Summary

CacheKey()

CacheKey(Object id)

Method Summary

boolean	equals(Object object) This method uses the id implementation of equals if the mo is null since this indicates that the id class did implement equals.
Object	getId()
int	hashCode() these should be overwritten by extending Cache key since they define what the cache does in the first place
void	readExternal(ObjectInput in)
String	toString()
void	writeExternal(ObjectOutput out)

Methods inherited from class java.lang.Object

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

Field Detail

id

protected Object id

The database primaryKey. This primaryKey is used by: org.jboss.ejb.plugins.EntityInstanceCache.setKey() - to set the EntityEnterpriseContext id org.jboss.ejb.plugins.jrmp.interfaces.EntityProxy.invoke(): - implementing Entity.toString() --> cacheKey.getId().toString() - implementing Entity.hashCode() --> cacheKey.getId().hashCode() - etc... org.jboss.ejb.plugins.local.BaseLocalProxyFactory.EntityProxy.getId()

mo

protected MarshalledObject mo

The Marshalled Object representing the key

hashCode

protected int hashCode

The Marshalled Object's hashcode

Constructor Detail

CacheKey

public CacheKey()

CacheKey

public CacheKey(Object id)

Method Detail

getId

public Object getId()

writeExternal

public void writeExternal(ObjectOutput out)
                   throws IOException

Specified by:

writeExternal in interface Externalizable

Throws:

IOException

readExternal

public void readExternal(ObjectInput in)
                  throws IOException,
                         ClassNotFoundException

Specified by:

readExternal in interface Externalizable

Throws:

IOException

ClassNotFoundException

hashCode

public int hashCode()

these should be overwritten by extending Cache key since they define what the cache does in the first place

equals

public boolean equals(Object object)

This method uses the id implementation of equals if the mo is null since this indicates that the id class did implement equals. If mo is not null, then the MarshalledObject equals is used to compare keys based on their serialized form. Relying on the serialized form does not always work.

toString

public String toString()