org.hibernate.action.internal.DelayedPostInsertIdentifier Maven / Gradle / Ivy
/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2008-2011, Red Hat Inc. or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat Inc.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program 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 distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.hibernate.action.internal;
import java.io.Serializable;
import java.util.concurrent.atomic.AtomicLong;
/**
* Acts as a stand-in for an entity identifier which is supposed to be
* generated on insert (like an IDENTITY column) where the insert needed to
* be delayed because we were outside a transaction when the persist
* occurred (save currently still performs the insert).
*
* The stand-in is only used within the {@link org.hibernate.engine.spi.PersistenceContext}
* in order to distinguish one instance from another; it is never injected into
* the entity instance or returned to the client...
*
* @author Steve Ebersole
* @author Sanne Grinovero
*/
public class DelayedPostInsertIdentifier implements Serializable, Comparable {
private static final AtomicLong SEQUENCE = new AtomicLong( 0 );
private final long identifier;
/**
* Constructs a DelayedPostInsertIdentifier
*/
public DelayedPostInsertIdentifier() {
long value = SEQUENCE.incrementAndGet();
if ( value < 0 ) {
synchronized (SEQUENCE) {
value = SEQUENCE.incrementAndGet();
if ( value < 0 ) {
SEQUENCE.set( 0 );
value = 0;
}
}
}
this.identifier = value;
}
@Override
public boolean equals(Object o) {
if ( this == o ) {
return true;
}
if ( o == null || getClass() != o.getClass() ) {
return false;
}
final DelayedPostInsertIdentifier that = (DelayedPostInsertIdentifier) o;
return identifier == that.identifier;
}
@Override
public int hashCode() {
return (int) ( identifier ^ ( identifier >>> 32 ) );
}
@Override
public String toString() {
return "";
}
@Override
public int compareTo(DelayedPostInsertIdentifier that) {
if ( this.identifier < that.identifier ) {
return -1;
}
else if ( this.identifier > that.identifier ) {
return 1;
}
else {
return 0;
}
}
}