100 Java Interview Questions

Here is the list of 100 Java interview questions

1. What is Java?
2. What are the key features of Java?
3. What is the difference between JDK, JRE, and JVM?
4. What is a class in Java?
5. What is an object in Java?
6. What is the difference between a class and an object?
7. What is inheritance in Java?
8. What is polymorphism in Java?
9. What is encapsulation in Java?
10. What is abstraction in Java?
11. What is a constructor in Java?
12. What is the purpose of the main() method in Java?
13. What is the final keyword in Java?
14. What is static keyword in Java?
15. What is an interface in Java?
16. What is an abstract class in Java?
17. What is a package in Java?
18. What is a string in Java?
19. What is a StringBuffer in Java?
20. What is a StringBuilder in Java?
21. What is the difference between StringBuffer and StringBuilder in Java?
22. What is an array in Java?
23. What is an ArrayList in Java?
24. What is a LinkedList in Java?
25. What is a Map in Java?
26. What is a Set in Java?
27. What is the difference between a List and a Set in Java?
28. What is a Iterator in Java?
29. What is a Comparator in Java?
30. What is a Thread in Java?
31. What is synchronization in Java?
32. What is the difference between wait() and sleep() methods in Java?
33. What is the difference between notify() and notifyAll() methods in Java?
34. What is a deadlock in Java?
35. What is the purpose of the synchronized keyword in Java?
36. What is a try-catch block in Java?
37. What is an exception in Java?
38. What is the difference between checked and unchecked exceptions in Java?
39. What is the purpose of throw keyword in Java?
40. What is the purpose of throws keyword in Java?
41. What is the difference between final, finally, and finalize in Java?
42. What is the purpose of the super keyword in Java?
43. What is the purpose of the this keyword in Java?
44. What is a lambda expression in Java?
45. What is a functional interface in Java?
46. What is a stream in Java?
47. What is a lambda expression in Java?
48. What is the difference between filter() and map() methods in Java?
49. What is the difference between a stream and a collection in Java?
50. What is the difference between findFirst() and findAny() methods in Java?
51. What is the purpose of Optional class in Java?
52. What is the difference between imperative and declarative programming in Java?
53. What is the purpose of the @Override annotation in Java?
54. What is a reflection in Java?
55. What is the purpose of the getClass() method in Java?
56. What is a ClassLoader in Java?
57. What is a jar file in Java?
58. What is a war file in Java?
59. What is a servlet in Java?
60. What is a JSP in Java?
61. What is a JDBC in Java?
62. What is a connection pool in Java?
63. What is a prepared statement in Java?
64. What is the difference between a Statement and a PreparedStatement in Java?
65. What is a Hibernate in Java?
66. What is a JPA in Java?
67. What is a Spring framework in Java?
68. What is the purpose of @Autowired annotation in Java?
69. What is the purpose of @Transactional annotation in Java?
70. What is the purpose of @RequestMapping annotation in Java?
71. What is the difference between @PathVariable and @RequestParam annotations in Java?
72. What is a Bean in Spring framework?
73. What is a dependency injection in Spring framework?
74. What is the difference between constructor injection and setter injection in Spring framework?
75. What is a scope in Spring framework?
76. What is the purpose of @Component annotation in Spring framework?
77. What is the purpose of @Configuration annotation in Spring framework?
78. What is the purpose of @Service annotation in Spring framework?
79. What is the purpose of @Repository annotation in Spring framework?
80. What is the purpose of @Controller annotation in Spring framework?
81. What is AOP in Spring framework?
82. What is the purpose of @Aspect annotation in Spring framework?
83. What is a proxy object in Spring framework?
84. What is a transaction in Spring framework?
85. What is a join point in AOP?
86. What is a pointcut in AOP?
87. What is an advice in AOP?
88. What is a weaving in AOP?
89. What is a CGLIB in Spring framework?
90. What is a JUnit in Java?
91. What is the purpose of @Test annotation in JUnit?
92. What is a Mockito in Java?
93. What is the purpose of @Mock annotation in Mockito?
94. What is the purpose of @InjectMocks annotation in Mockito?
95. What is a Maven in Java?
96. What is a Gradle in Java?
97. What is a Jenkins in Java?
98. What is a SonarQube in Java?
99. What is a JMeter in Java?
100. What is a SOAP in Java?

I hope these 100 Java interview questions will help you prepare well for your Java interview. Good luck!