1. | Given the code
String s1 = "yes";
String s2 = "yes";
String s3 = new String(s1);
Which of the following would equate to true?
(A) s1 == s2
(B) s1 = s2
(C) s3 == s1
(D) s1.equals(s2)
(E) s3.equals(s1) |
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Hint
Half-n-half Clue
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2. | Given the class definitions
class Base
{
void display ()
{ System.out.println("Base"); }
}
class Derived extends Base
{
void display ()
{ System.out.println("Derived"); }
}
and objects
Base b = new Base();
Derived d = new Derived();
Base bd = new Derived;
then the print statements
System.out.print(b.display() + " ");
System.out.print(d.display() + " ");
System.out.print(bd.display() + " ");
System.out.println();
will display: |
| | Half-n-half Clue
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3. | Which of the following statements are true?
(A) A Java monitor must either extend Thread or implement Runnable.
(B) The sleep() method should be enclosed in try ... catch block.
(C) The yield() method should be enclosed in try ... catch block.
(D) A thread can be temporarily suspended from running by using the wait() method.
(E) A suspended thread using suspend() method can be revived using the resume() method. |
| | Half-n-half Clue
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4. | Which of the following statements are valid array declaration?
(A) int number();
(B) float average[];
(C) double[] marks;
(D) counter int[]; |
| | Half-n-half Clue
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5. | Consider the following code
int number[] = new int[5]; After execution of this statement, which of the following are true?
(A) number[0] is undefined
(B) number[5] is undefined
(C) number[4] is null
(D) number[2] is 0
(E) number.length() is 5 |
| | Half-n-half Clue
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6. | Which of the following are the wrapper classes?
(A) Random
(B) Byte
(C) Vector
(D) Integer
(E) Short
(F) Double
(G) String |
| | Half-n-half Clue
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7. | Given the following code:
class Base { int x = 10; }
class Derived extends Base
{ int x = 20; }
Base b = new Base();
Derived d = new Derived ( );
Base bd = new Derived();
The statement
System.out.println(b.x + " " + d.x + " " + bd.x);
will produce the output |
| | Half-n-half Clue
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