/* Soot - a J*va Optimization Framework
* Copyright (C) 2007 Eric Bodden
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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 library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
package soot.jimple.toolkits.infoflow;
import java.util.WeakHashMap;
import soot.EquivalentValue;
import soot.Value;
/**
* An {@link EquivalentValue} with cached hash code and equals-relation.
* @author Eric Bodden
*/
public class CachedEquivalentValue extends EquivalentValue {
protected int code = Integer.MAX_VALUE;
protected WeakHashMap<Value, Boolean> isEquivalent = new WeakHashMap<Value, Boolean>();
public CachedEquivalentValue(Value e) {
super(e);
}
public int hashCode() {
if(code==Integer.MAX_VALUE) {
code = super.hashCode();
}
return code;
}
public boolean equals(Object o) {
if(this.getClass()!=o.getClass()) {
return false;
}
EquivalentValue ev = (EquivalentValue) o;
Value v = ev.getValue();
Boolean b = isEquivalent.get(v);
if(b==null) {
b = super.equals(o);
isEquivalent.put(v,b);
}
return b;
}
}