Java tutorial
//package com.java2s; /* * ==================================================================== * 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. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ public class Main { /** * Check if two objects are equal. * * @param obj1 first object to compare, may be {@code null} * @param obj2 second object to compare, may be {@code null} * @return {@code true} if the objects are equal or both null */ public static boolean equals(final Object obj1, final Object obj2) { return obj1 == null ? obj2 == null : obj1.equals(obj2); } /** * Check if two object arrays are equal. * <p> * <ul> * <li>If both parameters are null, return {@code true}</li> * <li>If one parameter is null, return {@code false}</li> * <li>If the array lengths are different, return {@code false}</li> * <li>Compare array elements using .equals(); return {@code false} if any comparisons fail.</li> * <li>Return {@code true}</li> * </ul> * * @param a1 first array to compare, may be {@code null} * @param a2 second array to compare, may be {@code null} * @return {@code true} if the arrays are equal or both null */ public static boolean equals(final Object[] a1, final Object[] a2) { if (a1 == null) { if (a2 == null) { return true; } else { return false; } } else { if (a2 != null && a1.length == a2.length) { for (int i = 0; i < a1.length; i++) { if (!equals(a1[i], a2[i])) { return false; } } return true; } else { return false; } } } }