io.logspace.agent.shaded.mchange.v1.identicator.WeakIdHashKey Maven / Gradle / Ivy
/*
* Distributed as part of c3p0 v.0.9.1.1
*
* Copyright (C) 2005 Machinery For Change, Inc.
*
* Author: Steve Waldman
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 2.1, as
* published by the Free Software Foundation.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this software; see the file LICENSE. If not, write to the
* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*/
package io.logspace.agent.shaded.mchange.v1.identicator;
import java.lang.ref.*;
// revisit equals() if ever made non-final
final class WeakIdHashKey extends IdHashKey
{
Ref keyRef;
int hash;
public WeakIdHashKey(Object keyObj, Identicator id, ReferenceQueue rq)
{
super( id );
if (keyObj == null)
throw new UnsupportedOperationException("Collection does not accept nulls!");
this.keyRef = new Ref( keyObj, rq );
this.hash = id.hash( keyObj );
}
public Ref getInternalRef()
{ return this.keyRef; }
public Object getKeyObj()
{ return keyRef.get(); }
public boolean equals(Object o)
{
// fast type-exact match for final class
if (o instanceof WeakIdHashKey)
{
WeakIdHashKey other = (WeakIdHashKey) o;
if (this.keyRef == other.keyRef)
return true;
else
{
Object myKeyObj = this.keyRef.get();
Object oKeyObj = other.keyRef.get();
if (myKeyObj == null || oKeyObj == null)
return false;
else
return id.identical( myKeyObj, oKeyObj );
}
}
else
return false;
}
public int hashCode()
{ return hash; }
class Ref extends WeakReference
{
public Ref( Object referant, ReferenceQueue rq )
{ super( referant, rq ); }
WeakIdHashKey getKey()
{ return WeakIdHashKey.this; }
}
}