001 /* 002 * Created on Apr 12, 2009 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with 005 * the License. You may obtain a copy of the License at 006 * 007 * http://www.apache.org/licenses/LICENSE-2.0 008 * 009 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on 010 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the 011 * specific language governing permissions and limitations under the License. 012 * 013 * Copyright @2009 the original author or authors. 014 */ 015 package org.fest.test; 016 017 /** 018 * Understands verification of the equals/hashCode contract. 019 * 020 * @author Alex Ruiz 021 */ 022 public interface EqualsHashCodeContractTestCase { 023 024 void should_not_be_equal_to_Object_not_being_of_same_type(); 025 026 /** 027 * If two objects are equal, they must remain equal as long as they are not modified. 028 */ 029 void should_have_consistent_equals(); 030 031 /** 032 * The object must be equal to itself, which it would be at any given instance; unless you intentionally override the 033 * equals method to behave otherwise. 034 */ 035 void should_have_reflexive_equals(); 036 037 /** 038 * If object of one class is equal to another class object, the other class object must be equal to this class object. 039 * In other words, one object can not unilaterally decide whether it is equal to another object; two objects, and 040 * consequently the classes to which they belong, must bilaterally decide if they are equal or not. They BOTH must 041 * agree. 042 */ 043 void should_have_symmetric_equals(); 044 045 /** 046 * If the first object is equal to the second object and the second object is equal to the third object; then the 047 * first object is equal to the third object. In other words, if two objects agree that they are equal, and follow the 048 * symmetry principle, one of them can not decide to have a similar contract with another object of different class. 049 * All three must agree and follow symmetry principle for various permutations of these three classes. 050 */ 051 void should_have_transitive_equals(); 052 053 /** 054 * If two objects are equal, then they must have the same hash code, however the opposite is NOT true. 055 */ 056 void should_maintain_equals_and_hashCode_contract(); 057 058 /** 059 * Verifies that the implementation of the method <code>equals</code> returns <code>false</code> if a 060 * <code>null</code> is passed as argument. 061 */ 062 void should_not_be_equal_to_null(); 063 }