1 /* 2 * Copyright (C) 2009 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.util.concurrent; 18 19 import static com.google.common.truth.Truth.assertThat; 20 21 import com.google.common.annotations.GwtCompatible; 22 import com.google.common.annotations.GwtIncompatible; 23 import com.google.common.base.Supplier; 24 import com.google.common.base.Suppliers; 25 import java.security.Permission; 26 import java.util.concurrent.Callable; 27 import java.util.concurrent.ExecutionException; 28 import junit.framework.TestCase; 29 30 /** 31 * Unit tests for {@link Callables}. 32 * 33 * @author Isaac Shum 34 */ 35 @GwtCompatible(emulated = true) 36 public class CallablesTest extends TestCase { 37 testReturning()38 public void testReturning() throws Exception { 39 assertNull(Callables.returning(null).call()); 40 41 Object value = new Object(); 42 Callable<Object> callable = Callables.returning(value); 43 assertSame(value, callable.call()); 44 // Expect the same value on subsequent calls 45 assertSame(value, callable.call()); 46 } 47 48 @GwtIncompatible testAsAsyncCallable()49 public void testAsAsyncCallable() throws Exception { 50 final String expected = "MyCallableString"; 51 Callable<String> callable = 52 new Callable<String>() { 53 @Override 54 public String call() throws Exception { 55 return expected; 56 } 57 }; 58 59 AsyncCallable<String> asyncCallable = 60 Callables.asAsyncCallable(callable, MoreExecutors.newDirectExecutorService()); 61 62 ListenableFuture<String> future = asyncCallable.call(); 63 assertSame(expected, future.get()); 64 } 65 66 @GwtIncompatible testAsAsyncCallable_exception()67 public void testAsAsyncCallable_exception() throws Exception { 68 final Exception expected = new IllegalArgumentException(); 69 Callable<String> callable = 70 new Callable<String>() { 71 @Override 72 public String call() throws Exception { 73 throw expected; 74 } 75 }; 76 77 AsyncCallable<String> asyncCallable = 78 Callables.asAsyncCallable(callable, MoreExecutors.newDirectExecutorService()); 79 80 ListenableFuture<String> future = asyncCallable.call(); 81 try { 82 future.get(); 83 fail("Expected exception to be thrown"); 84 } catch (ExecutionException e) { 85 assertThat(e).hasCauseThat().isSameInstanceAs(expected); 86 } 87 } 88 89 @GwtIncompatible // threads testRenaming()90 public void testRenaming() throws Exception { 91 String oldName = Thread.currentThread().getName(); 92 final Supplier<String> newName = Suppliers.ofInstance("MyCrazyThreadName"); 93 Callable<Void> callable = 94 new Callable<Void>() { 95 @Override 96 public Void call() throws Exception { 97 assertEquals(Thread.currentThread().getName(), newName.get()); 98 return null; 99 } 100 }; 101 Callables.threadRenaming(callable, newName).call(); 102 assertEquals(oldName, Thread.currentThread().getName()); 103 } 104 105 @GwtIncompatible // threads testRenaming_exceptionalReturn()106 public void testRenaming_exceptionalReturn() throws Exception { 107 String oldName = Thread.currentThread().getName(); 108 final Supplier<String> newName = Suppliers.ofInstance("MyCrazyThreadName"); 109 class MyException extends Exception {} 110 Callable<Void> callable = 111 new Callable<Void>() { 112 @Override 113 public Void call() throws Exception { 114 assertEquals(Thread.currentThread().getName(), newName.get()); 115 throw new MyException(); 116 } 117 }; 118 try { 119 Callables.threadRenaming(callable, newName).call(); 120 fail(); 121 } catch (MyException expected) { 122 } 123 assertEquals(oldName, Thread.currentThread().getName()); 124 } 125 126 @GwtIncompatible // threads 127 testRenaming_noPermissions()128 public void testRenaming_noPermissions() throws Exception { 129 System.setSecurityManager( 130 new SecurityManager() { 131 @Override 132 public void checkAccess(Thread t) { 133 throw new SecurityException(); 134 } 135 136 @Override 137 public void checkPermission(Permission perm) { 138 // Do nothing so we can clear the security manager at the end 139 } 140 }); 141 try { 142 final String oldName = Thread.currentThread().getName(); 143 Supplier<String> newName = Suppliers.ofInstance("MyCrazyThreadName"); 144 Callable<Void> callable = 145 new Callable<Void>() { 146 @Override 147 public Void call() throws Exception { 148 assertEquals(Thread.currentThread().getName(), oldName); 149 return null; 150 } 151 }; 152 Callables.threadRenaming(callable, newName).call(); 153 assertEquals(oldName, Thread.currentThread().getName()); 154 } finally { 155 System.setSecurityManager(null); 156 } 157 } 158 } 159