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.CollectionSize.ZERO; 20 import static com.google.common.collect.testing.features.MapFeature.SUPPORTS_CLEAR; 21 22 import com.google.common.collect.testing.AbstractMapTester; 23 import com.google.common.collect.testing.features.CollectionSize; 24 import com.google.common.collect.testing.features.MapFeature; 25 26 /** 27 * A generic JUnit test which tests {@code clear()} operations on a map. 28 * Can't be invoked directly; please see 29 * {@link com.google.common.collect.testing.MapTestSuiteBuilder}. 30 * 31 * <p>This class is GWT compatible. 32 * 33 * @author George van den Driessche 34 * @author Chris Povirk 35 */ 36 public class MapClearTester<K, V> extends AbstractMapTester<K, V> { 37 @MapFeature.Require(SUPPORTS_CLEAR) testClear()38 public void testClear() { 39 getMap().clear(); 40 assertTrue("After clear(), a map should be empty.", 41 getMap().isEmpty()); 42 } 43 44 @MapFeature.Require(absent = SUPPORTS_CLEAR) 45 @CollectionSize.Require(absent = ZERO) testClear_unsupported()46 public void testClear_unsupported() { 47 try { 48 getMap().clear(); 49 fail("clear() should throw UnsupportedOperation if a map does " 50 + "not support it and is not empty."); 51 } catch (UnsupportedOperationException expected) { 52 } 53 expectUnchanged(); 54 } 55 56 @MapFeature.Require(absent = SUPPORTS_CLEAR) 57 @CollectionSize.Require(ZERO) testClear_unsupportedByEmptyCollection()58 public void testClear_unsupportedByEmptyCollection() { 59 try { 60 getMap().clear(); 61 } catch (UnsupportedOperationException tolerated) { 62 } 63 expectUnchanged(); 64 } 65 } 66