1 /* 2 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 /** 25 * @test 26 * @bug 8072726 27 * @summary Tests for Enumeration-to-Iterator conversion. 28 * @run testng EnumerationAsIterator 29 */ 30 31 import org.testng.annotations.DataProvider; 32 import org.testng.annotations.Test; 33 34 import java.util.ArrayList; 35 import java.util.Arrays; 36 import java.util.Collection; 37 import java.util.Collections; 38 import java.util.Enumeration; 39 import java.util.Iterator; 40 import java.util.List; 41 import java.util.NoSuchElementException; 42 import java.util.concurrent.atomic.AtomicInteger; 43 import java.util.function.Supplier; 44 45 import static org.testng.Assert.*; 46 47 @Test 48 public class EnumerationAsIterator { of(String description, Supplier<Enumeration<?>> s, Collection<?> exp)49 static Object[] of(String description, Supplier<Enumeration<?>> s, Collection<?> exp) { 50 return new Object[]{description, s, exp}; 51 } 52 of(String description, Collection<?> c, Collection<?> exp)53 static Object[] of(String description, Collection<?> c, Collection<?> exp) { 54 return of(description, () -> Collections.enumeration(c), exp); 55 } 56 57 /** 58 * A wrapper Enumeration that doesn't override the 59 * default method on Enumeration. 60 */ wrapInDefault(Enumeration<T> e)61 static <T> Enumeration<T> wrapInDefault(Enumeration<T> e) { 62 return new Enumeration<>() { 63 @Override 64 public boolean hasMoreElements() { 65 return e.hasMoreElements(); 66 } 67 68 @Override 69 public T nextElement() { 70 return e.nextElement(); 71 } 72 }; 73 } 74 75 @DataProvider 76 public static Iterator<Object[]> unmodifiable() { 77 return Arrays.asList( 78 of("Default-wrapped ArrayList", 79 () -> wrapInDefault( 80 Collections.enumeration(new ArrayList<>(Arrays.asList("a")))), 81 Arrays.asList("a")), 82 83 of("Unmodifiable ArrayList", 84 Collections.unmodifiableList(new ArrayList<>(Arrays.asList("a"))), 85 Arrays.asList("a")), 86 87 of("Modifiable ArrayList", 88 new ArrayList<>(Arrays.asList("a")), 89 Arrays.asList("a")) 90 ).iterator(); 91 } 92 93 @DataProvider 94 public static Iterator<Object[]> others() { 95 return Arrays.asList( 96 of("Default Collections.emptyEnumeration()", 97 () -> wrapInDefault(Collections.emptyEnumeration()), 98 Collections.emptyList()), 99 100 of("Collections.emptyEnumeration()", 101 Collections::emptyEnumeration, 102 Collections.emptyList()), 103 104 of("Collections.emptyList()", 105 Collections.emptyList(), 106 Collections.emptyList()), 107 108 of("Collections.singletonList()", 109 Collections.singletonList("a"), 110 Collections.singletonList("a")), 111 112 of("Arrays.asList(...)", 113 Arrays.asList("a", "b", "c"), 114 Arrays.asList("a", "b", "c")) 115 ).iterator(); 116 } 117 118 @DataProvider 119 public static Iterator<Object[]> all() { 120 List<Object[]> all = new ArrayList<>(); 121 unmodifiable().forEachRemaining(all::add); 122 others().forEachRemaining(all::add); 123 return all.iterator(); 124 } 125 126 @Test(dataProvider = "all") 127 public void consumeByNext(String description, Supplier<Enumeration<?>> s, Collection<?> exp) { 128 Iterator<?> i = s.get().asIterator(); 129 int count = 0; 130 while (i.hasNext()) { 131 assertTrue(i.hasNext()); 132 133 i.next(); 134 count++; 135 } 136 assertEquals(count, exp.size()); 137 138 assertFalse(i.hasNext()); 139 140 try { 141 i.next(); 142 fail(); 143 } catch (NoSuchElementException e) { 144 } 145 } 146 147 @Test(dataProvider = "all") 148 public void consumeByForEachRemaining(String description, 149 Supplier<Enumeration<?>> s, 150 Collection<?> exp) { 151 Iterator<?> i = s.get().asIterator(); 152 AtomicInteger ai = new AtomicInteger(); 153 i.forEachRemaining(e -> ai.getAndIncrement()); 154 assertEquals(ai.get(), exp.size()); 155 i.forEachRemaining(e -> ai.getAndIncrement()); 156 assertEquals(ai.get(), exp.size()); 157 158 assertFalse(i.hasNext()); 159 160 try { 161 i.next(); 162 fail(); 163 } catch (NoSuchElementException e) { 164 } 165 } 166 167 @Test(dataProvider = "all") 168 public void consumeByNextThenForEachRemaining(String description, 169 Supplier<Enumeration<?>> s, 170 Collection<?> exp) { 171 Iterator<?> i = s.get().asIterator(); 172 AtomicInteger ai = new AtomicInteger(); 173 if (i.hasNext()) { 174 i.next(); 175 ai.getAndIncrement(); 176 } 177 i.forEachRemaining(e -> ai.getAndIncrement()); 178 assertEquals(ai.get(), exp.size()); 179 i.forEachRemaining(e -> ai.getAndIncrement()); 180 assertEquals(ai.get(), exp.size()); 181 182 assertFalse(i.hasNext()); 183 184 try { 185 i.next(); 186 fail(); 187 } catch (NoSuchElementException e) { 188 } 189 } 190 191 @Test(dataProvider = "all") 192 public void contents(String description, Supplier<Enumeration<?>> s, Collection<?> exp) { 193 assertEquals(copy(s.get()), exp); 194 } 195 196 private List<?> copy(Enumeration<?> input) { 197 List<Object> output = new ArrayList<>(); 198 input.asIterator().forEachRemaining(output::add); 199 return output; 200 } 201 202 @Test(dataProvider = "unmodifiable", 203 expectedExceptions=UnsupportedOperationException.class) 204 public void removeThrowsAfterAdvancingE(String description, 205 Supplier<Enumeration<?>> s, 206 Collection<?> exp) { 207 Enumeration<?> e = s.get(); 208 e.nextElement(); 209 e.asIterator().remove(); 210 } 211 212 @Test(dataProvider = "unmodifiable", 213 expectedExceptions=UnsupportedOperationException.class) 214 public void removeThrowsAfterAdvancingI(String description, 215 Supplier<Enumeration<?>> s, 216 Collection<?> exp) { 217 Iterator<?> i = s.get().asIterator(); 218 i.next(); 219 i.remove(); 220 } 221 } 222