1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package libcore.java.util; 18 19 import java.util.Collection; 20 import java.util.ConcurrentModificationException; 21 import java.util.function.Predicate; 22 import java.util.function.Supplier; 23 24 import static junit.framework.Assert.assertTrue; 25 import static junit.framework.Assert.fail; 26 27 /** 28 * Tests behavior common to all implementations of {@link Collection#removeIf(Predicate)}. 29 */ 30 public class RemoveIfTester { 31 32 private static final Predicate<Integer> isEven = x -> x % 2 == 0; 33 private static final Predicate<Integer> isOdd = isEven.negate(); 34 runBasicRemoveIfTests(Supplier<Collection<Integer>> supp)35 public static void runBasicRemoveIfTests(Supplier<Collection<Integer>> supp) { 36 Collection<Integer> integers = supp.get(); 37 for (int h = 0; h < 100; ++h) { 38 // Insert some ordered integers. 39 integers.add(h); 40 } 41 42 integers.removeIf(isEven); 43 Integer prev = null; 44 for (Integer i : integers) { 45 assertTrue(i % 2 != 0); 46 if (prev != null) { 47 assertTrue(prev <= i); 48 } 49 prev = i; 50 } 51 52 integers.removeIf(isOdd); 53 assertTrue(integers.isEmpty()); 54 } 55 runBasicRemoveIfTestsUnordered(Supplier<Collection<Integer>> supp)56 public static void runBasicRemoveIfTestsUnordered(Supplier<Collection<Integer>> supp) { 57 Collection<Integer> integers = supp.get(); 58 for (int h = 0; h < 100; ++h) { 59 // Insert a bunch of arbitrary integers. 60 integers.add((h >>> 2) ^ (h >>> 5) ^ (h >>> 11) ^ (h >>> 17)); 61 } 62 63 integers.removeIf(isEven); 64 for (Integer i : integers) { 65 assertTrue(i % 2 != 0); 66 } 67 68 integers.removeIf(isOdd); 69 assertTrue(integers.isEmpty()); 70 } 71 72 /** 73 * Removing from an empty collection should not fail. 74 */ runRemoveIfOnEmpty(Supplier<Collection<Integer>> supp)75 public static void runRemoveIfOnEmpty(Supplier<Collection<Integer>> supp) { 76 supp.get().removeIf(x -> { 77 fail(); 78 return false; 79 }); 80 } 81 testRemoveIfNPE(Supplier<Collection<Integer>> supp)82 public static void testRemoveIfNPE(Supplier<Collection<Integer>> supp) { 83 try { 84 supp.get().removeIf(null); 85 fail(); 86 } catch (NullPointerException expected) {} 87 } 88 testRemoveIfCME(Supplier<Collection<Integer>> supp)89 public static void testRemoveIfCME(Supplier<Collection<Integer>> supp) { 90 Collection<Integer> c = supp.get(); 91 c.add(0); 92 93 try { 94 c.removeIf(x -> {c.add(42); return true;}); 95 fail(); 96 } catch (ConcurrentModificationException expected) { 97 } 98 } 99 } 100