/* Soot - a J*va Optimization Framework
* Copyright (C) 2004 Ondrej Lhotak
*
* 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.util;
/** A Lisp-style cons cell. */
public final class Cons {
public Cons( Object car, Object cdr ) {
this.car = car;
this.cdr = cdr;
}
final private Object car;
final private Object cdr;
public int hashCode() {
int ret = 0;
if( car != null ) ret += car.hashCode();
if( cdr != null ) ret += cdr.hashCode();
return ret;
}
public boolean equals(Object o) {
if( !( o instanceof Cons ) ) return false;
Cons other = (Cons) o;
if( car == null ) {
if( other.car != null ) return false;
} else {
if( !car.equals(other.car) ) return false;
}
if( cdr == null ) {
if( other.cdr != null ) return false;
} else {
if( !cdr.equals(other.cdr) ) return false;
}
return true;
}
public Object car() { return car; }
public Object cdr() { return cdr; }
}