JAVA THREADS QUIZ

In java a thread can be created by ..........

Implementing Runnable interface.

Extending the thread class.

Both of the above

None of these

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What will be the output?class A extends Thread{ public void run(){ for(int i=0; i<2; i++){ System.out.println(i); } }}public class Test{ public static void main(String argv[]){ Test t = new Test(); t.check(new A(){}); } public void check(A a){ a.start(); }}

0 0

None of these

0 1

Compilation error, class A has no start method

Compilation succeed but runtime exception

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Analyze the following code:public class Test implements Runnable{ public static void main(String[] args){ Test t = new Test(); } public Test(){ Thread t = new Thread(this); t.start(); } public void run(){ System.out.println("test"); }}

The program compiles and runs and displays nothing.

The program has a compilation error because t is defined in both the main() method and the constructor Test().

The program compiles and runs and displays test.

The program compiles fine, but it does not run because you cannot use the keyword this in the constructor.

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What is the output for the below code ?public class Test extends Thread{ public static void main(String argv[]){ Test t = new Test(); t.run(); } public void start(){ for(int i = 0; i < 10; i++){ System.out.println("Value of i = " + i); } }}

Clean compile but no output at runtime

Clean compile and at run time the values 0 to 9 are printed out

A compile time error indicating that no run method is defined for the Thread class

A run time error indicating that no run method is defined for the Thread class

None of these

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Which of the following constructor of class Thread is valid one?

Thread(Runnable threadOb, int priority)

Thread(Runnable threadOb, String threadName)

None of these

Thread(int priority)

Thread(String threadName, int priority)

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Which keyword when applied on a method indicates that only one thread should execute the method at a time.

static

native

volatile

final

synchronized

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Analyze the following code:public class Test implements Runnable{ public static void main(String[] args){ Test t = new Test(); t.start(); } public void run() { }}

The program compiles, but it does not run because the run() method is not implemented.

The program compiles and runs fine.

The program compiles, but it does not run because the start() method is not defined.

The program does not compile because the start() method is not defined in the Test class.

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Which of the following are methods of the Thread class?1) yield()2) sleep(long msec)3) go()4) stop()

1 , 2 and 4

None of these

3 only

1 and 3

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When a class extends the Thread class ,it should override ............ method of Thread class to start that thread.

go()

init()

run()

start()

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What notifyAll() method do?

Wakes up one threads that are waiting on this object's monitor

None of these

Wakes up all threads that are not waiting on this object's monitor

Wakes up all threads that are waiting on this object's monitor

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