| 1) What is the size of a Char? |
| a) 4 bits |
| b) 7 bits |
| c) 8 bits |
| d) 16 bits - correct answer |
| 2) A class cannot be declared: |
| a) Static |
| b) Private - correct answer |
| c) Default |
| 3) Following code will result in: int a = 3.5; |
| a) Compilation error - correct answer |
| b) Runtime error |
| c) a being 3.5 |
| d) a being 3. |
| 4) Following code will result in: int a1 = 5; double a2 = (float)a1; |
| a) Compilation error |
| b) Runtime error |
| c) No errors - correct answer |
| 5) Following code will result in: int a = 9/0; |
| a) Compilation error: Divisions must be in a try block. |
| b) Compilation error: DivideByZeroException |
| c) Runtime Exception - correct answer |
| d) No Error: a is NaN |
| 6) Following code will result in: float a = 9/0; |
| a) Compilation error: Divisions must be in a try block |
| b) Compilation error: DivideByZeroException |
| c) Runtime Exception - correct answer |
| d) No Error: a is NaN |
| 7) A class can be transient |
| a) True |
| b) False - correct answer |
| 8) Following code will result in: class A { int b = 1; public static void main(String [] args) {System.out.println("b is " + b); }} |
| a) Compilation error - correct answer |
| b) Runtime Error |
| c) Runtime Exception |
| d) Output of b is 1 |
| 9) Following code will result in: class A { public static void main(String [] args) {B b = new A(); }} class B extends A {} |
| a) Compile error - correct answer |
| b) Runtime Exception |
| c) No error |
| 10) Following code will result in: class A { public static void main(String [] args) {A a = new B(); }} class B extends A {} |
| a) Compiler error |
| b) Runtime Exception |
| c) No errors - correct answer |
| 11) Methods that are marked protected can be called in any subclass of that class. |
| a) True - correct answer |
| b) False |
| 12) An abstract class can have non-abstract methods. |
| a) True - correct answer |
| b) False |
| 13) Java keywords are written in lowercase as well as uppercase. |
| a) True |
| b) False - correct answer |
| 14) What is an instanceof |
| a) A methods in object |
| b) An operator and keyword - correct answer |
| 15) Primitive datatypes are allocated on a stack. |
| a) True - correct answer |
| b) False |
| 16) Can you compare a boolean to an integer? |
| a) Yes |
| b) No - correct answer |
| 17) If class A implements an interface does it need to implement all methods of that interface? |
| a) Yes, always. |
| b) No, not when A is abstract - correct answer |
| 18) Integer a = new Integer(2); Integer b = new Integer(2); What happens when you do if (a==b)? |
| a) Compiler error |
| b) Runtime Exception |
| c) True |
| d) False - correct answer |
| 19) The methods wait(), notify() and notifyAll() in Object need to be called from synchronized pieces of code. |
| a) True - correct answer |
| b) False |
| 20) Inner classes can be defined within methods. |
| a) True - correct answer |
| b) False |
| 21) Synchronized is a keyword to tell a Thread to grab an Object lock before continuing execution. |
| a) True - correct answer |
| b) False |
| 22) The default statement of a switch is always executed. |
| a) True |
| b) False - correct answer |
| 23) How can you prevent a member variable from becoming serialized? |
| a) By marking it private |
| b) By marking it volatile |
| c) By marking it transient - correct answer |
| d) You can not. |
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