src/java/org/apache/commons/functor/core/comparator/ComparableComparator.java

/*
 * Copyright 2003,2004 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.commons.functor.core.comparator;

import java.io.Serializable;
import java.util.Comparator;

/**
 * See Commons-Collections for a public version 
 * of this class.
 * 
 * @version $Revision$ $Date$
 * @author Rodney Waldhoff
 */
final class ComparableComparator implements Comparator, Serializable {
    public ComparableComparator() {
    }
 
    /**
     * @see java.util.Comparator#compare(Object, Object)
     */
    public int compare(Object o1, Object o2) {
        return ((Comparable)o1).compareTo(o2);
    }
    
    /**
     * @see java.lang.Object#equals(Object)
     */
    public boolean equals(Object obj) {
        return (obj instanceof ComparableComparator);
    }

    /**
     * @see java.lang.Object#hashCode()
     */
    public int hashCode() {
        return toString().hashCode();
    }

    /**
     * @see java.lang.Object#toString()
     */
    public String toString() {
        return" ComparableComparator";
    }
    
    public static final ComparableComparator instance() {
        return INSTANCE;
    }
    
    public static final ComparableComparator INSTANCE = new ComparableComparator();

}