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  • Question
  • What will be the output of the program?
    String s = "hello"; 
    Object o = s; 
    if( o.equals(s) )
    {
        System.out.println("A"); 
    } 
    else
    {
        System.out.println("B"); 
    } 
    if( s.equals(o) )
    {
        System.out.println("C"); 
    } 
    else
    { 
        System.out.println("D"); 
    }
    
    1. A
    2. B
    3. C
    4. D


  • Options
  • A. 1 and 3
  • B. 2 and 4
  • C. 3 and 4
  • D. 1 and 2

  • Correct Answer
  • 1 and 3 


  • Java.lang Class problems


    Search Results


    • 1. What will be the output of the program?
      class Q207 
      { 
          public static void main(String[] args) 
          {
              int i1 = 5; 
              int i2 = 6; 
              String s1 = "7"; 
              System.out.println(i1 + i2 + s1); /* Line 8 */
          } 
      }
      

    • Options
    • A. 18
    • B. 117
    • C. 567
    • D. Compiler error
    • Discuss
    • 2. What will be the output of the program?
      interface Foo141 
      { 
          int k = 0; /* Line 3 */
      } 
      public class Test141 implements Foo141 
      {
          public static void main(String args[]) 
          {
              int i; 
              Test141 test141 = new Test141(); 
              i = test141.k; /* Line 11 */
              i = Test141.k; 
              i = Foo141.k; 
          } 
      }
      

    • Options
    • A. Compilation fails.
    • B. Compiles and runs ok.
    • C. Compiles but throws an Exception at runtime.
    • D. Compiles but throws a RuntimeException at runtime.
    • Discuss
    • 3. What will be the output of the program?
      public class SqrtExample 
      {
          public static void main(String [] args) 
          {
              double value = -9.0;
              System.out.println( Math.sqrt(value));
          }
      }
      

    • Options
    • A. 3.0
    • B. -3.0
    • C. NaN
    • D. Compilation fails.
    • Discuss
    • 4. What will be the output of the program?
      String a = "ABCD"; 
      String b = a.toLowerCase(); 
      b.replace('a','d'); 
      b.replace('b','c'); 
      System.out.println(b);
      

    • Options
    • A. abcd
    • B. ABCD
    • C. dccd
    • D. dcba
    • Discuss
    • 5. What will be the output of the program?
      public class BoolTest 
      {
          public static void main(String [] args) 
          {
              int result = 0;
      
              Boolean b1 = new Boolean("TRUE");
              Boolean b2 = new Boolean("true");
              Boolean b3 = new Boolean("tRuE");
              Boolean b4 = new Boolean("false");
      
              if (b1 == b2)  /* Line 10 */
                  result = 1;
              if (b1.equals(b2) ) /* Line 12 */
                  result = result + 10;
              if (b2 == b4)  /* Line 14 */
                  result = result + 100;
              if (b2.equals(b4) ) /* Line 16 */
                  result = result + 1000;
              if (b2.equals(b3) ) /* Line 18 */
                  result = result + 10000;
      
              System.out.println("result = " + result);
          }
      }
      

    • Options
    • A. 0
    • B. 1
    • C. 10
    • D. 10010
    • Discuss
    • 6. What will be the output of the program?
      public class ObjComp 
      {
          public static void main(String [] args ) 
          {
              int result = 0;
              ObjComp oc = new ObjComp();
              Object o = oc;
      
              if (o == oc)  
                  result = 1;
              if (o != oc)  
                  result = result + 10;
              if (o.equals(oc) )  
                  result = result + 100;
              if (oc.equals(o) )  
                  result = result + 1000;
      
              System.out.println("result = " + result);
          }
      }
      

    • Options
    • A. 1
    • B. 10
    • C. 101
    • D. 1101
    • Discuss
    • 7. What will be the output of the program?
      public class Example 
      {
          public static void main(String [] args) 
          {
              double values[] = {-2.3, -1.0, 0.25, 4};
              int cnt = 0;
              for (int x=0; x < values.length; x++) 
              {
                  if (Math.round(values[x] + .5) == Math.ceil(values[x])) 
                  {
                      ++cnt;
                  }
              }
              System.out.println("same results " + cnt + " time(s)");
          }
      }
      

    • Options
    • A. same results 0 time(s)
    • B. same results 2 time(s)
    • C. same results 4 time(s)
    • D. Compilation fails.
    • Discuss
    • 8. What will be the output of the program?
      class Tree { } 
      class Pine extends Tree { } 
      class Oak extends Tree { } 
      public class Forest1 
      { 
          public static void main (String [] args)
          { 
              Tree tree = new Pine(); 
              if( tree instanceof Pine ) 
                  System.out.println ("Pine"); 
              else if( tree instanceof Tree ) 
                  System.out.println ("Tree"); 
              else if( tree instanceof Oak ) 
                  System.out.println ( "Oak" ); 
              else 
                  System.out.println ("Oops "); 
          } 
      }
      

    • Options
    • A. Pine
    • B. Tree
    • C. Forest
    • D. Oops
    • Discuss
    • 9. What will be the output of the program?
      public class WrapTest 
      {
          public static void main(String [] args) 
          {
              int result = 0;
              short s = 42;
              Long x = new Long("42");
              Long y = new Long(42);
              Short z = new Short("42");
              Short x2 = new Short(s);
              Integer y2 = new Integer("42");
              Integer z2 = new Integer(42);
      
              if (x == y) /* Line 13 */
                  result = 1;
              if (x.equals(y) ) /* Line 15 */
                  result = result + 10;
              if (x.equals(z) ) /* Line 17 */
                  result = result + 100;
              if (x.equals(x2) ) /* Line 19 */
                  result = result + 1000;
              if (x.equals(z2) ) /* Line 21 */
                  result = result + 10000;
      
              System.out.println("result = " + result);
          }
      }
      

    • Options
    • A. result = 1
    • B. result = 10
    • C. result = 11
    • D. result = 11010
    • Discuss
    • 10. What will be the output of the program?
      String x = "xyz";
      x.toUpperCase(); /* Line 2 */
      String y = x.replace('Y', 'y');
      y = y + "abc";
      System.out.println(y);
      

    • Options
    • A. abcXyZ
    • B. abcxyz
    • C. xyzabc
    • D. XyZabc
    • Discuss


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