JAVA THREADS QUIZ

What will be output of the following program code?public class Test implements Runnable{ public void run(){ System.out.print("go"); } public static void main(String arg[]) { Thread t = new Thread(new Test()); t.run(); t.run(); t.start(); }}

An exception is thrown at runtime.

"gogogo" is printed

"go" is printed

"gogo" is printed

Compilation fails.

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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

Compilation succeed but runtime exception

0 1

Compilation error, class A has no start method

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

None of these

1 and 3

1 , 2 and 4

3 only

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

Implementing Runnable interface.

None of these

Extending the thread class.

Both of the above

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

run()

start()

go()

init()

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What will be the output?class One extends Thread{public void run(){for(int i=0; i<2; i++){System.out.print(i);}}}public class Test{public static void main(String args[]){Test t = new Test();t.call(new One());} public void call(One o){o.start();}}

Compilation Error

0 0

None of these

0 1

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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 start() method is not defined.

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

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

The program compiles and runs fine.

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What will be the output of the following program code?public class Test implements Runnable{ public static void main(String[] args){ Thread t = new Thread(this); t.start(); } public void run(){ System.out.println("test"); }}

The program compiles fine, but it does not print anything because t does not invoke the run() method

None of these

The program does not compile because this cannot be referenced in a static method.

The program compiles and runs fine and displays test on the console.

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Predict the output:public class Test extends Thread{ private int i; public void run(){ i++; } public static void main(String[] args){ Test a = new Test(); a.run(); System.out.print(a.i); a.start(); System.out.print(a.i); }}

Prints

Compiler error

IllegalThreadStateException is thrown

Prints

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Analyze the following code:public abstract class Test implements Runnable{ public void doSomething() { };}

The program compiles fine.

The program will not compile because it does not contain abstract methods.

None of these

The program will not compile because it does not implement the run() method.

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