oracle.toplink.essentials.internal.identitymaps.WeakCacheKey Maven / Gradle / Ivy
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package oracle.toplink.essentials.internal.identitymaps;
import java.lang.ref.*;
import java.util.Vector;
/**
* Purpose: Container class for storing objects in an IdentityMap.
* The weak cache key uses a weak reference to allow garbage collection of its object.
* The cache key itself however will remain and thus should cleaned up every no and then.
*
Responsibilities:
* - Hold key and object.
*
- Maintain and update the current writeLockValue.
*
* @since TOPLink/Java 1.0
*/
public class WeakCacheKey extends CacheKey {
/** Reference is maintained weak to allow garbage collection */
protected WeakReference reference;
/**
* Initialize the newly allocated instance of this class.
* @param primaryKey contains values extracted from the object
* @param writeLockValue is the write lock value, null if optimistic locking not being used for this object.
* @param readTime the time TopLInk read the cache key
*/
public WeakCacheKey(Vector primaryKey, Object object, Object writeLockValue, long readTime) {
super(primaryKey, object, writeLockValue, readTime);
}
public Object getObject() {
return getReference().get();
}
public WeakReference getReference() {
return reference;
}
public void setObject(Object object) {
setReference(new WeakReference(object));
}
protected void setReference(WeakReference reference) {
this.reference = reference;
}
}