Which of these will create and start this thread?

public class MyRunnable implements Runnable 
{
    public void run() 
    {
        // some code here
    }
}

Option A is correct. wait() causes the current thread to wait until another thread invokes the notify() method or the notifyAll() method for this object.

Option B is wrong. notify() - wakes up a single thread that is waiting on this object's monitor.

Option C is wrong. notifyAll() - wakes up all threads that are waiting on this object's monitor.

Option D is wrong. Typically, releasing a lock means the thread holding the lock (in other words, the thread currently in the synchronized method) exits the synchronized method. At that point, the lock is free until some other thread enters a synchronized method on that object. Does entering/exiting synchronized code mean that the thread execution stops? Not necessarily because the thread can still run code that is not synchronized. I think the word directly in the question gives us a clue. Exiting synchronized code does not directly stop the execution of a thread.

Option B is Correct. The start() method causes this thread to begin execution; the Java Virtual Machine calls the run method of this thread.

Option A is wrong. There is no init() method in the Thread class.

Option C is wrong. The run() method of a thread is like the main() method to an application. Starting the thread causes the object's run method to be called in that separately executing thread.

Option D is wrong. The resume() method is deprecated. It resumes a suspended thread.

Option A. Either of the two events (notification or wait time expiration) will make the thread become a candidate for running again.

Option B is incorrect because a waiting thread will not return to runnable when the lock is released, unless a notification occurs.

Option C is incorrect because the thread will become a candidate immediately after notification, not two seconds afterwards.

Option D is also incorrect because a thread will not come out of a waiting pool just because a lock has been released.

Option A is Correct. The run() method to a thread is like the main() method to an application. Starting the thread causes the object's run method to be called in that separately executing thread.

Option B is wrong. The start() method causes this thread to begin execution; the Java Virtual Machine calls the run method of this thread.

Option C is wrong. The stop() method is deprecated. It forces the thread to stop executing.

Option D is wrong. Is the main entry point for an application.

The Object class defines these thread-specific methods.

Option B, C, and D are incorrect because they do not define these methods. And yes, the Java API does define a class called Class, though you do not need to know it for the exam.

In argCopy[0] = args;, the reference variable argCopy[0], which was referring to an array with two elements, is reassigned to an array ( args) with three elements.

The names array is initialized with five null elements. Then elements 0 and 1 are assigned the String values "a" and "b" respectively (the command-line arguments passed to main). Elements of names array 2, 3, and 4 remain unassigned, so they have a value of null.

An exception is thrown because at some point in (System.out.print(" " + argh[y]);), the value of x will be equal to y, resulting in an attempt to access an index out of bounds for the array. Remember that you can access only as far as length - 1, so loop logical tests should use x < someArray.length as opposed to x < = someArray.length.

The second dimension of the array referenced by theDogs has not been initialized. Attempting to access an uninitialized object element (System.out.println(theDogs[2][0].toString());) raises a NullPointerException.