Q31 In Java, how is a 'static' variable different from an 'instance' variable?

Q32 What is polymorphism in Java?

Q33 What distinguishes an abstract class from a regular class in Java?

Q34 What will the following code output:
class Test {
static int x = 10;
} public class Main {
public static void main(String[] args) {
Test t1 = new Test(); System.out.println(t1.x); } }

Q35 Determine the output of this pseudocode:

CLASS Animal METHOD sound PRINT "Generic Sound" END CLASS Dog EXTENDS Animal METHOD sound PRINT "Bark" END CLASS Main CREATE Dog d CALL d.sound

Q36 What will be the result of this pseudocode?

CLASS Book VARIABLE title = "Java Programming" METHOD getTitle PRINT title END CLASS Main CREATE Book b CALL b.getTitle

Q37 Analyze this pseudocode:

CLASS Shape METHOD area RETURN 0 END CLASS Circle EXTENDS Shape VARIABLE radius = 5 METHOD area RETURN 3.14 * radius * radius END CLASS Main CREATE Circle c PRINT c.area

Q38 Identify the issue in this code snippet:
class Book {
private String title; void setTitle(String title) {
title = title; }
}

Q39 Find the error in this Java code:
class Animal {
Animal() {
System.out.println("An animal is created");
}
} class Dog extends Animal {
Dog() { super();
System.out.println("A dog is created");
}
} public class Main {
public static void main(String[] args) {
Dog dog = new Dog();
}
}

Q40 How does StringBuilder differ from StringBuffer in Java?

Q41 In Java, what is an interface?

Q42 Can an interface in Java contain default methods?

Q43 Can an interface in Java extend multiple interfaces?

Q44 Analyze the output of this code snippet:
interface A {
int val = 5;
}
interface B extends A {
int val = 10;
}
class Test implements B {
void display() {
System.out.println(val);
}
} public class Main {
public static void main(String[] args) {
Test t = new Test();
t.display();
}
}

Q45 What does the 'import' statement do in a Java program?

Q46 What is the significance of the CLASSPATH environment variable in Java?

Q47 What is an exception in Java?

Q48 What happens if an exception is thrown in a try block and is not caught in the corresponding catch block?

Q49 What is the difference between checked and unchecked exceptions in Java?

Q50 Analyze the output of this code snippet:
try {
int[] arr = new int[5];
arr[10] = 100;
System.out.println("Value set");
}
catch (ArrayIndexOutOfBoundsException e) {
System.out.println("Index Error");
}

Q51 Determine the output of this pseudocode:
TRY PRINT "Start" THROW NEW EXCEPTION "Failed" CATCH EXCEPTION PRINT "Caught" END TRY PRINT "End"

Q52 Identify the issue in this code snippet:
try {
int x = 5 / 0;
}
catch (Exception e) {
e.printStackTrace();
}
finally {
System.out.println("Done");
}

Q53 Find the error in this Java code:
try {
File file = new File("test.txt");
FileReader fr = new FileReader(file);
}
catch (FileNotFoundException e) {
System.out.println("File not found");
}

Q54 Identify the flaw in this Java code:
class CustomException extends Exception { }
try {
throw new CustomException();
}
catch (CustomException e) {
System.out.println("Custom exception caught");
}

Q55 What are generics in Java?

Q56 Which collection type does not allow duplicate elements?

Q57 Analyze the output of this code snippet:
List list = new ArrayList<>();
list.add("Java");
list.add("Java");
System.out.println(list.get(1));

Q58 What will be the result of this pseudocode?

CREATE map SET map["Java"] = 1 SET map["Python"] = 2 SET map["Java"] = 3 PRINT map["Java"]

Q59 What will this pseudocode output?

CREATE map SET map[1] = "Java" SET map[2] = "Python" SET map[1] = "C++" PRINT map[1]

Q60 Spot the mistake:
Set set = new TreeSet<>(); set.add(null);