Newgen Placement Paper -: Java Questions With Answers

Newgen Previous Years Solved Sample Placement Papers

1. What will be the output of the following Java code?

   
   class newthread extends Thread
   {
       Thread t;
       newthread()
       {
           t1 = new Thread(this, "Thread_1");
           t2 = new Thread(this, "Thread_2");
           t1.start();
           t2.start();
       }
       public void run()
       {
           t2.setPriority(Thread.MAX_PRIORITY);    
           System.out.print(t1.equals(t2));
       }    
   }
   class multithreaded_programing
   {
       public static void main(String args[])
       {
           new newthread();        
       }
   }
       

   A: truetrue

   B: falsefalse

   C: true

   D: false

   Ans: B

   Explanation:

   This program was previously done by using Runnable interface, here we have used Thread class. This shows both methods are equivalent, we can use any of them to create a thread.

   Output:

   
   $ javac multithreaded_programing.java
   $ java multithreaded_programing
   falsefalse
       

2. Which one of the following is not an access modifier?

   A: Protected

   B: Void

   C: Public

   D: Private

   Ans: B

   Explanation:

   Public, private, protected and default are the access modifiers.

3. What will be the output of the following Java program?

   
   final class A 
   {
       int i;
   }    
   class B extends A 
   {
       int j;
       System.out.println(j + " " + i);  
   }    
   class inheritance 
   {
       public static void main(String args[])
       {
           B obj = new B();
           obj.display();     
       }
   }
       

   A: 2 2

   B: 3 3

   C: Runtime Error

   D: Compilation Error

   Ans: D

   Explanation:

   Class A has been declared final hence it cannot be inherited by any other class. Hence class B does not have member i, giving compilation error.

   Output:

   
   $ javac inheritance.java
   Exception in thread "main" java.lang.Error: Unresolved compilation problem: 
       i cannot be resolved or is not a field
       

4. What is the numerical range of a char data type in Java?

   A: 0 to 256

   B: -128 to 127

   C: 0 to 65535

   D: 0 to 32767

   Ans: C

   Explanation:

   Char occupies 16-bit in memory, so it supports 216 i:e from 0 to 65535.

5. Which class provides system independent server side implementation?

   A: Server

   B: ServerReader

   C: Socket

   D: ServerSocket

   Ans: D

   Explanation:

   ServerSocket is a java.net class which provides system independent implementation of server side socket connection.