228 Which three will compile and run without exception? (Choose three.) 

 1. private synchronized Object o; 

 2. 

 3. public synchronized void go(){/* code here */} 

 4. private synchronized(this) void go(){/* code here */} 

 5. 

 6. 
(A) 123
(B) 235
(C) 356
(D) 456

223 Which statement is true? (A) The output could be 5-1 6-1 6-2 5-2 (B) The output could be 6-1 6-2 5-1 5-2 (C) The output could be 6-1 5-2 6-2 5-1 (D) The output could be 6-1 6-2 5-1 7-1

224 What is the result? (A) Compilation fails. (B) An exception is thrown at runtime. (C) The code executes normally and prints "foo"; (D) The code executes normally, but nothing is printed.

複選題226 Which two statements are true? (Choose two.) (A) It is possible to synchronize static methods. (B) When a thread has yielded as a result of yield(), it releases its locks. (C) When a thread is sleeping as a result of sleep(), it releases its locks. (D) The Object.wait() method can be invoked only from a synchronized context. (E) The Thread.sleep() method can be invoked only from a synchronized context. (AB) When the thread scheduler receives a notify() request, and notifies a thread, that thread immediately releases its lock.

227 What can be a result? (A) Compilation fails. (B) An exception is thrown at runtime. (C) The code executes and prints "StartedComplete". (D) The code executes and prints "StartedComplete0123". (E) The code executes and prints "Started0123Complete".

複選題229 Which two changes, taken together, would guarantee the output: 1, 2, 3, 4, 5, ? (Choose two.) (A) move the line 12 print statement into the foo() method (B) change line 7 to public synchronized void go(){ (C) change the variable declaration on line 2 to private volatile int x; (D) wrap the code inside the foo() method with a synchronized(this) block (E) wrap the for loop code inside the go() method with a synchronized block synchronized(this){//for loop code here}

230 Given that t1 is a reference to a live thread, which is true? (A) The Thread.sleep() method can take t1 as an argument. (B) The Object.notify() method can take t1 as an argument. (C) The Thread.yield() method can take t1 as an argument. (D) The Thread.setPriority() method can take t1 as an argument. (E) The Object.notify() method arbitrarily chooses which thread to notify.

231 What is the result? (A) Cat (B) Dog (C) Compilation fails. (D) The code runs with no output. (E) An exception is thrown at runtime.

232 What is the result? (A) Compilation fails. (B) An exception is thrown at runtime. (C) The code executes normally and prints "bar". (D) The code executes normally, but nothing prints.

複選題233 Which two are possible results? (Choose two.) (A) 0, 2, 4, 4, 6, 8, 10, 6, (B) 0, 2, 4, 6, 8, 10, 2, 4, (C) 0, 2, 4, 6, 8, 10, 12, 14, (D) 0, 0, 2, 2, 4, 4, 6, 6, 8, 8, 10, 10, 12, 12, 14, 14, (E) 0, 2, 4, 6, 8, 10, 12, 14, 0, 2, 4, 6, 8, 10, 12, 14,

234 From another thread, what provides the most reliable way to ensure that foo will stop executing wait()? (A) foo.notify(); (B) bar.notify(); (C) foo.notifyAll(); (D) Thread.notify(); (E) bar.notifyAll(); (AB) Object.notify();