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1. 

What will be the output of the program? 

public class Q126 implements Runnable 
{ 
    private int x; 
    private int y; 

    public static void main(String [] args) 
    { 
        Q126 that = new Q126(); 
        (new Thread(that)).start( ); /* Line 8 */
        (new Thread(that)).start( ); /* Line 9 */
    } 
    public synchronized void run( ) /* Line 11 */
    { 
        for (;;) /* Line 13 */
        { 
            x++; 
            y++; 
            System.out.println("x = " + x + "y = " + y); 
        } 
    } 
}

A. An error at line 11 causes compilation to fail
B. Errors at lines 8 and 9 cause compilation to fail.
C. The program prints pairs of values for x and y that might not always be the same on the same line (for example, "x=2, y=1")
D. The program prints pairs of values for x and y that are always the same on the same line (for example, "x=1, y=1". In addition, each value appears once (for example, "x=1, y=1" followed by "x=2, y=2")
2. 

What will be the output of the program? 

class MyThread extends Thread 
{ 
    MyThread() {} 
    MyThread(Runnable r) {super(r); } 
    public void run() 
    { 
        System.out.print("Inside Thread ");
    } 
} 
class MyRunnable implements Runnable 
{ 
    public void run() 
    { 
        System.out.print(" Inside Runnable"); 
    } 
} 
class Test 
{  
    public static void main(String[] args) 
    { 
        new MyThread().start(); 
        new MyThread(new MyRunnable()).start(); 
    } 
}

A. Prints "Inside Thread Inside Thread"
B. Prints "Inside Thread Inside Runnable"
C. Does not compile
D. Throws exception at runtime
3. 

What will be the output of the program? 

class s1 implements Runnable 
{ 
    int x = 0, y = 0; 
    int addX() {x++; return x;} 
    int addY() {y++; return y;} 
    public void run() { 
    for(int i = 0; i < 10; i++) 
        System.out.println(addX() + " " + addY()); 
} 
    public static void main(String args[]) 
    { 
        s1 run1 = new s1(); 
        s1 run2 = new s1(); 
        Thread t1 = new Thread(run1); 
        Thread t2 = new Thread(run2); 
        t1.start(); 
        t2.start(); 
    } 
}
A. Compile time Error: There is no start() method
B. Will print in this order: 1 1 2 2 3 3 4 4 5 5...
C. Will print but not exactly in an order (e.g: 1 1 2 2 1 1 3 3...)
D. Will print in this order: 1 2 3 4 5 6... 1 2 3 4 5 6...
4. 

What will be the output of the program? 

class MyThread extends Thread 
{
    public static void main(String [] args) 
    {
        MyThread t = new MyThread();
        t.start();
        System.out.print("one. ");
        t.start();
        System.out.print("two. ");
    }
    public void run() 
    {
        System.out.print("Thread ");
    }
}

A. Compilation fails
B. An exception occurs at runtime.
C. It prints "Thread one. Thread two."
D. The output cannot be determined.
5. 

What will be the output of the program? 

class s1 extends Thread
{ 
    public void run() 
    { 
        for(int i = 0; i < 3; i++) 
        { 
            System.out.println("A"); 
            System.out.println("B"); 
        } 
    } 
} 
class Test120 extends Thread 
{ 
    public void run() 
    { 
        for(int i = 0; i < 3; i++) 
        { 
            System.out.println("C"); 
            System.out.println("D"); 
        } 
    } 
    public static void main(String args[]) 
        { 
        s1 t1 = new s1(); 
        Test120 t2 = new Test120(); 
        t1.start(); 
        t2.start(); 
    } 
}

A. Compile time Error There is no start() method
B. Will print in this order AB CD AB...
C. Will print but not be able to predict the Order
D. Will print in this order ABCD...ABCD...