1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package org.apache.harmony.tests.java.util; 19 20 import java.util.EmptyStackException; 21 import java.util.Stack; 22 23 public class StackTest extends junit.framework.TestCase { 24 25 Stack s; 26 27 /** 28 * java.util.Stack#Stack() 29 */ 30 public void test_Constructor() { 31 // Test for method java.util.Stack() 32 assertEquals("Stack creation failed", 0, s.size()); 33 } 34 35 /** 36 * java.util.Stack#empty() 37 */ 38 public void test_empty() { 39 // Test for method boolean java.util.Stack.empty() 40 assertTrue("New stack answers non-empty", s.empty()); 41 s.push("blah"); 42 assertTrue("Stack should not be empty but answers empty", !s.empty()); 43 s.pop(); 44 assertTrue("Stack should be empty but answers non-empty", s.empty()); 45 s.push(null); 46 assertTrue("Stack with null should not be empty but answers empty", !s 47 .empty()); 48 } 49 50 /** 51 * java.util.Stack#peek() 52 */ 53 public void test_peek() { 54 // Test for method java.lang.Object java.util.Stack.peek() 55 String item1 = "Ichi"; 56 String item2 = "Ni"; 57 String item3 = "San"; 58 s.push(item1); 59 assertTrue("Peek did not return top item when it was the only item", s 60 .peek() == item1); 61 s.push(item2); 62 s.push(item3); 63 assertTrue("Peek did not return top item amoung many other items", s 64 .peek() == item3); 65 s.pop(); 66 assertTrue("Peek did not return top item after a pop", s.pop() == item2); 67 s.push(null); 68 assertNull("Peek did not return top item (wanted: null)", 69 s.peek()); 70 s.pop(); 71 s.pop(); 72 try { 73 s.pop(); 74 fail("EmptyStackException expected"); 75 } catch (EmptyStackException e) { 76 //expected 77 } 78 } 79 80 /** 81 * java.util.Stack#pop() 82 */ 83 public void test_pop() { 84 // Test for method java.lang.Object java.util.Stack.pop() 85 String item1 = "Ichi"; 86 String item2 = "Ni"; 87 Object lastPopped; 88 s.push(item1); 89 s.push(item2); 90 91 try { 92 lastPopped = s.pop(); 93 assertTrue("a) Pop did not return top item", lastPopped == item2); 94 } catch (EmptyStackException e) { 95 fail( 96 "a) Pop threw EmptyStackException when stack should not have been empty"); 97 } 98 99 try { 100 lastPopped = s.pop(); 101 assertTrue("b) Pop did not return top item", lastPopped == item1); 102 } catch (EmptyStackException e) { 103 fail( 104 "b) Pop threw EmptyStackException when stack should not have been empty"); 105 } 106 107 s.push(null); 108 try { 109 lastPopped = s.pop(); 110 assertNull("c) Pop did not return top item", lastPopped); 111 } catch (EmptyStackException e) { 112 fail( 113 "c) Pop threw EmptyStackException when stack should not have been empty"); 114 } 115 116 try { 117 lastPopped = s.pop(); 118 fail( 119 "d) Pop did not throw EmptyStackException when stack should have been empty"); 120 } catch (EmptyStackException e) { 121 return; 122 } 123 124 } 125 126 /** 127 * java.util.Stack#push(java.lang.Object) 128 */ 129 public void test_pushLjava_lang_Object() { 130 Object [] array = {new Integer(0), new Object(), 131 new Float(0), new String()}; 132 133 Stack<Object> stack = new Stack<Object>(); 134 for(int i = 0; i < array.length; i++) { 135 stack.push(array[i]); 136 } 137 for(int i = 0; i < array.length; i++) { 138 assertEquals(array.length - i, stack.search(array[i])); 139 } 140 } 141 142 /** 143 * java.util.Stack#search(java.lang.Object) 144 */ 145 public void test_searchLjava_lang_Object() { 146 // Test for method int java.util.Stack.search(java.lang.Object) 147 String item1 = "Ichi"; 148 String item2 = "Ni"; 149 String item3 = "San"; 150 s.push(item1); 151 s.push(item2); 152 s.push(item3); 153 assertEquals("Search returned incorrect value for equivalent object", 3, s 154 .search(item1)); 155 assertEquals("Search returned incorrect value for equal object", 3, s 156 .search("Ichi")); 157 s.pop(); 158 assertEquals("Search returned incorrect value for equivalent object at top of stack", 159 1, s.search(item2)); 160 assertEquals("Search returned incorrect value for equal object at top of stack", 161 1, s.search("Ni")); 162 s.push(null); 163 assertEquals("Search returned incorrect value for search for null at top of stack", 164 1, s.search(null)); 165 s.push("Shi"); 166 assertEquals("Search returned incorrect value for search for null", 2, s 167 .search(null)); 168 s.pop(); 169 s.pop(); 170 assertEquals("Search returned incorrect value for search for null--wanted -1", 171 -1, s.search(null)); 172 } 173 174 static class BugStack<E> extends Stack<E> { 175 public void setLength(int elementCount) { 176 this.elementCount = elementCount; 177 } 178 179 public int getLength() { 180 return elementCount; 181 } 182 } 183 184 //test for wrong exception threw by pop method 185 public void test_pop_modify_elementCount() { 186 BugStack<String> testStack = new BugStack<String>(); 187 testStack.push("A"); 188 testStack.push("B"); 189 testStack.setLength(20); 190 try { 191 testStack.pop(); 192 fail("Should throw ArrayIndexOutOfBoundsException here"); 193 } catch (ArrayIndexOutOfBoundsException e) { 194 //Expected to throw ArrayIndexOutOfBoundsException here 195 } catch (EmptyStackException e) { 196 fail("Should throw ArrayIndexOutOfBoundsException here"); 197 } 198 } 199 200 /** 201 * Sets up the fixture, for example, open a network connection. This method 202 * is called before a test is executed. 203 */ 204 protected void setUp() { 205 s = new Stack(); 206 } 207 208 /** 209 * Tears down the fixture, for example, close a network connection. This 210 * method is called after a test is executed. 211 */ 212 protected void tearDown() { 213 } 214 } 215
