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A library jar that provides APIs for Applications written for the Google Android Platform.

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/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You 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 java.util;

/**
 * A {@code Comparator} is used to compare two objects to determine their ordering with
 * respect to each other. On a given {@code Collection}, a {@code Comparator} can be used to
 * obtain a sorted {@code Collection} which is totally ordered. For a {@code Comparator}
 * to be consistent with equals, its {code #compare(Object, Object)}
 * method has to return zero for each pair of elements (a,b) where a.equals(b)
 * holds true. It is recommended that a {@code Comparator} implements
 * {@link java.io.Serializable}.
 *
 * @since 1.2
 */
public interface Comparator {
    /**
     * Compares the two specified objects to determine their relative ordering. The ordering
     * implied by the return value of this method for all possible pairs of
     * {@code (lhs, rhs)} should form an equivalence relation.
     * This means that
     * 
    *
  • {@code compare(a,a)} returns zero for all {@code a}
  • *
  • the sign of {@code compare(a,b)} must be the opposite of the sign of {@code * compare(b,a)} for all pairs of (a,b)
  • *
  • From {@code compare(a,b) > 0} and {@code compare(b,c) > 0} it must * follow {@code compare(a,c) > 0} for all possible combinations of {@code * (a,b,c)}
  • *
* * @param lhs * an {@code Object}. * @param rhs * a second {@code Object} to compare with {@code lhs}. * @return an integer < 0 if {@code lhs} is less than {@code rhs}, 0 if they are * equal, and > 0 if {@code lhs} is greater than {@code rhs}. * @throws ClassCastException * if objects are not of the correct type. */ public int compare(T lhs, T rhs); /** * Compares this {@code Comparator} with the specified {@code Object} and indicates whether they * are equal. In order to be equal, {@code object} must represent the same object * as this instance using a class-specific comparison. *

* A {@code Comparator} never needs to override this method, but may choose so for * performance reasons. * * @param object * the {@code Object} to compare with this comparator. * @return boolean {@code true} if specified {@code Object} is the same as this * {@code Object}, and {@code false} otherwise. * @see Object#hashCode * @see Object#equals */ public boolean equals(Object object); }





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