1 /* 2 * Copyright (C) 2008 The Guava Authors 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 com.google.common.collect.testing.testers; 18 19 import static com.google.common.collect.testing.features.CollectionFeature.SUPPORTS_CLEAR; 20 import static com.google.common.collect.testing.features.CollectionSize.ZERO; 21 22 import com.google.common.collect.testing.AbstractCollectionTester; 23 import com.google.common.collect.testing.features.CollectionFeature; 24 import com.google.common.collect.testing.features.CollectionSize; 25 26 /** 27 * A generic JUnit test which tests {@code clear()} operations on a collection. 28 * Can't be invoked directly; please see 29 * {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}. 30 * 31 * <p>This class is GWT compatible. 32 * 33 * @author George van den Driessche 34 */ 35 public class CollectionClearTester<E> extends AbstractCollectionTester<E> { 36 @CollectionFeature.Require(SUPPORTS_CLEAR) testClear()37 public void testClear() { 38 collection.clear(); 39 assertTrue("After clear(), a collection should be empty.", 40 collection.isEmpty()); 41 } 42 43 @CollectionFeature.Require(absent = SUPPORTS_CLEAR) 44 @CollectionSize.Require(absent = ZERO) testClear_unsupported()45 public void testClear_unsupported() { 46 try { 47 collection.clear(); 48 fail("clear() should throw UnsupportedOperation if a collection does " 49 + "not support it and is not empty."); 50 } catch (UnsupportedOperationException expected) { 51 } 52 expectUnchanged(); 53 } 54 55 @CollectionFeature.Require(absent = SUPPORTS_CLEAR) 56 @CollectionSize.Require(ZERO) testClear_unsupportedByEmptyCollection()57 public void testClear_unsupportedByEmptyCollection() { 58 try { 59 collection.clear(); 60 } catch (UnsupportedOperationException tolerated) { 61 } 62 expectUnchanged(); 63 } 64 } 65