/*
* NOTE: This copyright does *not* cover user programs that use HQ
* program services by normal system calls through the application
* program interfaces provided as part of the Hyperic Plug-in Development
* Kit or the Hyperic Client Development Kit - this is merely considered
* normal use of the program, and does *not* fall under the heading of
* "derived work".
*
* Copyright (C) [2004, 2005, 2006], Hyperic, Inc.
* This file is part of HQ.
*
* HQ is free software; you can redistribute it and/or modify
* it under the terms version 2 of the GNU 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 General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA.
*/
package org.hyperic.hibernate;
/**
* A utility class for checking equality and generating hash codes for persisted
* objects that use a numeric primary key as their logical identifier.
*/
class LogicalIdentityHelper {
private LogicalIdentityHelper() {
}
/**
* Check if the object to check is equal to this object.
*
* @param thisObject This object.
* @param toCheck The object to check.
* @return <code>true</code> if the object to check is equal to this object.
*/
public static boolean equals(PersistedObject thisObject, Object toCheck) {
if (thisObject == toCheck) {
return true;
}
if (toCheck == null || !(toCheck instanceof PersistedObject)) {
return false;
}
PersistedObject o = (PersistedObject)toCheck;
return equals(thisObject.getId(), o.getId());
}
/**
* Check if the object to check is equal to this object.
*
* @param thisObject This object.
* @param toCheck The object to check.
* @return <code>true</code> if the object to check is equal to this object.
*/
public static boolean equals(LongIdPersistedObject thisObject, Object toCheck) {
if (thisObject == toCheck) {
return true;
}
if (toCheck == null || !(toCheck instanceof LongIdPersistedObject)) {
return false;
}
LongIdPersistedObject o = (LongIdPersistedObject)toCheck;
return equals(thisObject.getId(), o.getId());
}
private static boolean equals(Number thisObjectId, Number toCheckObjectId) {
return thisObjectId == toCheckObjectId ||
(thisObjectId != null &&
toCheckObjectId != null &&
thisObjectId.equals(toCheckObjectId));
}
/**
* Generate a hash code for this object.
*
* @param thisObject This object.
* @return The hash code for this object.
*/
public static int hashCode(PersistedObject thisObject) {
return hashCode(thisObject.getId());
}
/**
* Generate a hash code for this object.
*
* @param thisObject This object.
* @return The hash code for this object.
*/
public static int hashCode(LongIdPersistedObject thisObject) {
return hashCode(thisObject.getId());
}
private static int hashCode(Number num) {
int result = 17;
result = 37*result + (num != null ? num.hashCode() : 0);
return result;
}
}