Disclaimer: The answers provided are AI-generated and may contain inaccuracies. Please verify the answers before use.
1. Which provides a runtime environment for Java byte code to be executed?
Answer: b. JVM
2. Which of the following are not Java keywords?
Answer: c. then
3. The default value of a static integer variable of a class in Java is,
Answer: a. 0
4. Multiple inheritance means,
Answer: a. one class inheriting from more superclasses
5. Which statement is not true in the Java language?
Answer: b. A private member of a class cannot be accessed by the methods of the same class (False).
6. To prevent any method from overriding, we declare the method as,
Answer: c. final
7. Which one of the following is not true?
Answer: c. An abstract class cannot have non-abstract methods (False).
8. The fields in an interface are implicitly specified as,
Answer: d. both static and final
9. Which of the following is true?
Answer: c. A finally block is executed whether an exception is thrown or not.
10. What is garbage collection in the context of Java?
Answer: c. When all references to an object are gone, the memory used by the object is automatically reclaimed.
11. The Java runtime system automatically calls this method while garbage collection.
Answer: b. finalize()
12. The correct order of the declarations in a Java program is,
Answer: a. Package declaration, import statement, class declaration
13. An overloaded method consists of,
Answer: d. Both (a) and (b) above
14. A protected member can be accessed in, Which is the false option?
Answer: b. non-subclass of the same package (False).
15. All exception types are subclasses of the built-in class
Answer: d. Throwable
16. When an overridden method is called from within a subclass, it will always refer to the version of that method defined by the
Answer: b. Subclass
17. Java compiler javac translates Java source code into
Answer: b. Byte code
18. In Java, a character constant’s value is its integer value in the
Answer: b. Unicode
19. In Java, a try block should immediately be followed by one or more .................... blocks.
Answer: d. Catch
20. An abstract data type typically comprises a ............... and a set of .................. respectively.
Answer: d. Data representation, operations.
21. Which method can be defined only once in a program?
Answer: b. finalize method
22. Which concept of Java is a way of converting real world objects in terms of class?
Answer: c. Abstraction
23. Declaring a method final means:
Answer: d. It cannot be overridden.
24. Which of the following statements regarding static methods are correct?
Answer: c. 2 and 4
25. Which statements are correct for the given case?
Answer: c. UberTaxi.taxiBooking() is a valid invocation of taxiBooking()
26. Which of the following statements is/are true about constructor?
Answer: c. Only (i) and (iii) are true
27. Which of the following is true about the use of java access modifiers?
Answer: b. You cannot specify accessibility of local variables. They are only accessible within the block in which they are declared.
28. When will thread A become a candidate to get another turn to execute after calling wait(4000)?
Answer: b. After object B is notified, or after four seconds.
29. Which exception class could be used to produce a suitable catch block for Integer.parseInt("one")?
Answer: c. NumberFormatException
30. When compared java.io.BufferedWriter to java.io.FileWriter, which extra capability does exist in only one of the two as a method?
Answer: d. writing a line separator to the stream
31. Which of the following is/are true about packages in Java?
Answer: b. Only 1, 2 and 3
32. How to propagate the unchecked Exceptions?
Answer: d. Unchecked exceptions are automatically propagated
33. Which of the following is true about generics in Java?
Answer: d. All of the mentioned
34. Which collection class helps you to expand or shrink its size and gives its elements indexed access, but whose techniques are not synchronised?
Answer: c. java.util.ArrayList
35. Given that Thing is a class, how many objects and how many reference variables are created by the given code?
Answer: c. Two objects are created. Three reference variables are created.
36. Can data flow through a given stream in both directions?
Answer: b. No; a stream has one direction only, input or output.
37. What are valid statements for daemon threads?
Answer: d. All of above.
38. What is difference between starting thread with run() and start() method?
Answer: a. When you call start() method, main thread internally calls run() method to start newly created Thread.
39. What are the rules applicable to define multiple try, catch & finally blocks?
Answer: a. 1,2,3
40. An abstract data type typically comprises a ............... and a set of .................. respectively.
Answer: d. Data representation, operations
41. Which of the following primitive data types are not integer types? Select the two correct answers.
Answer: b) float, d) double
42. Which one of the following array declaration statements is not legal? Select the one correct answer.
Answer: c) int a[][] = new int [][4];
43. Given the following declaration: char c = 'A'; What is the simplest way to convert the character value in c into an int? Select the one correct answer.
Answer: a) int i = c;
44. Which of the following expressions evaluate to true? Select the two correct answers.
Answer: a) (false | true), c) (4 <= 4)
45. Which is true? (Choose all that apply.)
Answer: c) "X extends Y" is correct if X and Y are either both classes or both interfaces
46. Is this comment correct?
public class JavaComment{
public static void main(String a[]){
System.out.pri/* my comment line*/ntln("Is this comment correct?");
}
}Answer: Yes, the comment is correctly placed. The compiler ignores the text between /* and */.
47. A java interface can contain _______.
Answer: d. public static Final Variables and abstract methods both
48. Which class is used to create a thread in Java?
Answer: a. Thread
49. What happens when a constructor is defined for an interface?
Answer: a. Compilation failure
50. What happens when we access the same variable defined in two interfaces implemented by the same class?
Answer: a. The interfaceName.variableName needs to be defined
51. Suppose you are working in a Java project. You have a requirement where you need a dynamic or resizable array-like data structure that can allow you to add, remove, and access elements at a specific index efficiently. It should also automatically adjust its size as elements are added or removed. Which of the following class will you use to fulfil your requirement?
Answer: c) ArrayList
52. Which of these is a super class of all errors and exceptions in the Java language?
Answer: b. Throwable
53. What is the output of this program?
Answer cannot be determined without seeing the code.
54. File Class is inside which package?
Answer: d. java.io
55. Which method is used to reads one byte of data from the input stream?
Answer: c) read()
56. The input stream is used to read data from numerous input devices like the keyboard, network, etc.
Answer: a. TRUE
57. Scope of the local variable is_________
Answer: b) Within the Method or block
58. What is the difference between constructor method and method?
Answer: a) Constructor will be automatically invoked when an object is created. Whereas method has to be call explicitly.
59. When a string literal is used in the program, Java automatically creates instances of the string class.
Answer: a) True
60. What is the result of expression 5.45 + "3.2"?
Answer: d) The String "5.453.2"
61. What is an example of polymorphism?
Answer: c) Method overloading
62. What is the result of executing the following code when the value of x is 2:
Cannot be determined without seeing the code.
63. What is the effect of compiling and (if possible) running this class:
class Example {
public static void main(String[] args) {
// Example code here
}
}Cannot be determined without seeing the class code.
64. What will be the result of compiling and running the following program?
class Pra1 {
public static void main(String[] args) {
byte[][] ba={{1,2,3,4},{1,2,3}};
System.out.println(ba[1].length+" "+ba.length);
}
}Answer: a) 3 2
66. Find the output / error of below java code.
class Pra1 {
public static void main(String[] args) {
int x=32;
int y=2;
if((x<y) && (++x<32))
System.out.println(x++);
System.out.println(x);
}
}Answer: b) 33