Test Your Java 3

Test Your Java 7 and Test Your Java 8 are advanced questions. Answers are given for each question at the end of each test. Answering these questions increases your knowledge in Java and helps you a lot when you appear for interviews. Solving these basic questions is your first step for Certification Exams preparation.

Test Your Java 3

1. Arrays in Java work differently than what they do in C/C++.
   a) True b) False
2. Arrays are
   a) objects b) object references c) primitive data types d) none
3. char[] c = new char();
   char[] c = new char(4);
   char[] c = new char[];
   All the above three statements are invalid.
   a) True b) False
4. int[] intarray1 = new int[] { 10, 20 };
   int[] intarray2 = { 10, 20 };

   We can form an array in the either way of the above statements.
   a) True b) False

5. int intarray[3] = { 10, 20, 30 };
   System.out.println(intarray[1]);
   The fraction of code outputs 20.
   a) True b) False
6. It is possible to change the size of the array once it is created.
   a) True b) False
7. .

        public class ZeroValue   
        {
          public static void main(String args[])    
          {
            Integer x[] = new Integer[3];
            System.out.println(x[0]);            
          }       
        }
   

   what is the output of the above println statement?
   a) 0 b) 1 c) null d) does not compile e) throws exception

8. int rates[] = {10, 20, 30 };
   System.out.println(rates.length());
   What is the output of the above fragment of code?
   a) 0 b) 2 c) 3 d) does not compile e) throws exception f) none
9. .

        class ArrayArgument    
        {
          void display(int arrays[])   
          {   
            System.out.println(arrays[0] += 2);   
          }
          public static void main(String args[])    
          {
            int intarray[] = { 5, 10, 15 };
            ArrayArgument arrarg = new ArrayArgument();
            arrarg.display(intarray);
            System.out.println(intarray[0]);
          }          
        }

   The above program
   a) both println statements prints the same value 7. b) one println prints 7 and the other 5 c) does not compile. d) compiles but throws an exception e) none

10. Java, like C/C++, treates text string as an array of characters.
    a) True b) False
11. String s1 = "RAMA\nKRISHNA";
    System.out.println(s1);
    The above fraction code prints the output in two different lines.
    a) True b) False
12. String s1 = new String("Hello");
    String s2 = new String("Hellow");
    System.out.println(s1 = s2);
    The output of the above fraction of code is
    a) Hello b) Hellow c) does not compile d) throws an exception e) none
13. .

         class LogicalCompare        
         {
           public static void main(String args[])      
           {
             String  str1 = new String("OKAY");
             String  str2  =  new String(str1);
             System.out.println(str1 == str2);
           }
         } 

    What is the output of the above program?
    a) displays error message b) true c) false d) 0 e) 1 f ) none

14. String s1 = "java";
    String s2 = "java";
    System.out.println(s1.equals(s2));
    System.out.println(s1 == s2);
    Both the above println statements returns true.
    a) True b) False
15. String s1 = "SITHA" ;
    String s2 = "RAMA";
    System.out.println(s1.charAt(0) > s2.charAt(0));
    What is the output of the above code ?
    a) True b) False c) 0 d) does not compile e) throws exception f)none
16. stringWidth() method is defined in _______________ class.
    a) String b) AWT c) Font d) FontMetrics e) none
17. String x = "hellow";
    int y = 9;
    System.out.println(x += y);
    What could be output of the above fragment of code?
    a) does not compile b) throws an exception as string and int are not compatible for addition c) hellow9 d) 9hellow e) none
18. toString() method is defined in
    a) java.lang.String b) java.lang.Object c) java.lang.util d) none
19. "Toolbar".startsWith("bar", 4);
    The above statement returns
    a) False b) True c) does not return any thing d) displays error message e) none
20. The String method compareTo() returns
    a) True b) False c) int value d) 1 e) -1 f) none
21. String str1 = "abcde";
    System.out.println(str1.substring(1, 3));
    The above program prints bc.
    a) True b) False
22. String str1 = "Hellow";
    System.out.println(str1.indexOf('t'));
    What is the output of the above println statement
    a) True b) False c) 1 d) -1 e) 0 f) displays error message g) none
23. .

         class ConcatEqual
         {
           public static void main (String args[])     
           {
             String str1 = "one";;
             String str2 = "two";
             System.out.println(str1.concat(str2).equals(str1 + str2)); 		
           }     
         }

    a) 0 b) 1 c) no output d) -1 e) True f) False g) displays error message h) none

24. String str1 = "Helloww".replace('l', 'w');
    In the above statement, the effect on string Helloww is
    a) the last occurrence of character w is replaced by l b) the first occurrence of l is replaced by w. c) all characters l are replaced by w.
    d) all characters w are replaced by l. e) displays error message
    f) the first occurrence of w is replaced by l. g) none

25. char ch = 'x';
    System.out.println(String.valueOf(ch));
    What could be output of the above fragment of code ?
    a) Unicode value of character x. b) x c) displays error message d) none

ANSWERS

1. a	2. a	3. a	4. a	5. b
6. b	7. c	8. d	9. a	10. b
11. a	12. b	13. c	14. a	15. a
16. d	17. c	18. b	19. b	20. c
21. a	22. d	23. e	24. c	25. b

Your Rating

Correct Answers
1 to 5 : Poor
6 t0 10: Below average
11 t0 15: Average
16 to 20: Good
Above 20: Extraordinary

Pass your comments and suggestions for the improvement of this "Test Your Java 3".