Question 1

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

A. Thread(Runnable threadOb, int priority) B. Thread(int priority) C. Thread(Runnable threadOb, String threadName) D. Thread(String threadName, int priority)

Question 2

What is the output for the below code? <pre class="prettyprint"> class A implements Runnable{ public void run(){ System.out.println(Thread.currentThread().getName()); } } 1. public class Test{ 2. public static void main(String... args){ 3. A a = new A(); 4. Thread t = new Thread(a); 5. t.setName("good"); 6. t.start(); 7. } 8. } </pre>

A. good B. null C. Compilation fails with an error at line 5 D. Compilation succeed but Runtime Exception

Question 3

Predict the output: <pre class="prettyprint"> 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); } } </pre>

A. Prints B. Prints C. Prints D. Compiler error

Question 4

What will be the output after compiling and executing the following code? <pre class="prettyprint"> public class Test implements Runnable{ public static void main(String[] args) throws InterruptedException{ Thread a = new Thread(new Test()); a.start(); System.out.print("Begin"); a.join(); System.out.print("End"); } public void run(){ System.out.print("Run"); } } </pre>

A. Compilation fails. B. An exception is thrown at runtime. C. "BeginRunEnd" is printed. D. "BeginEndRun" is printed.

Question 5

What will be the output of the following program code? <pre class="prettyprint"> 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"); } } </pre>

A. The program does not compile because this cannot be referenced in a static method. B. The program compiles fine, but it does not print anything because t does not invoke the run() method C. The program compiles and runs fine and displays test on the console. D. None of the above

Question 6

Given the code. What will be the result? <pre class="prettyprint"> public class Test implements Runnable{ public static void main(String[] args) throws InterruptedException{ Thread a = new Thread(new Test()); a.start(); System.out.print("Begin"); a.join(); System.out.print("End"); } public void run(){ System.out.print("Run"); } } </pre>

A. Compilation fails. B. An exception is thrown at runtime. C. "BeginRunEnd" is printed. D. "BeginEndRun" is printed.

Question 7

What will be the output? <pre class="prettyprint"> 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(); } } </pre>

A. 0 0 B. Compilation Error C. 0 1 D. None of these

Question 8

What will happen when you attempt to compile and run the following code? <pre class="prettyprint"> 1. public class Test extends Thread{ 2. public static void main(String argv[]){ 3. Test t = new Test(); 4. t.run(); 5. t.start(); 6. } 7. public void run(){ 8. System.out.println("run-test"); 9. } 10. } </pre>

A. run-test run-test B. run-test C. Compilation fails due to an error on line 4 D. Compilation fails due to an error on line 7

Question 9

Analyze the following code: <pre class="prettyprint"> 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"); } } </pre>

A. The program has a compilation error because t is defined in both the main() method and the constructor Test(). B. The program compiles fine, but it does not run because you cannot use the keyword this in the constructor. C. The program compiles and runs and displays nothing. D. The program compiles and runs and displays test.

Question 10

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

A. 1 , 2 and 4 B. 1 and 3 C. 3 only D. None of the above

Java thread MCQ