// Copyright (c) 2002, Eric D. Friedman All Rights Reserved.

package gnu.trove;

import java.io.Serializable;

/**
 * Interface to support pluggable hashing strategies in maps and sets.
 * Implementors can use this interface to make the trove hashing
 * algorithms use object values, values provided by the java runtime,
 * or a custom strategy when computing hashcodes.
 * 
 * Created: Sat Aug 17 10:52:32 2002
 *
 * @author Eric Friedman
 * @version $Id: TObjectHashingStrategy.java,v 1.1 2002/08/18 16:43:15 ericdf Exp $
 */

public interface TObjectHashingStrategy extends Serializable {
    
    /**
     * Computes a hash code for the specified object.  Implementors
     * can use the object's own hashCode method, the Java
     * runtime's identityHashCode, or a custom scheme.
     * 
     * @param object for which the hashcode is to be computed
     * @return the hashCode
     */
    public int computeHashCode(Object o);

    /**
     * Compares o1 and o2 for equality.  Strategy implementors may use
     * the objects' own equals() methods, compare object references,
     * or implement some custom scheme.
     *
     * @param o1 an Object value
     * @param o2 an Object value
     * @return true if the objects are equal according to this strategy.
     */
    public boolean equals(Object o1, Object o2);
} // TObjectHashingStrategy