Core Java - Level I

Practice 30 Core Java - Level I interview questions with detailed answers. Part of the Core Java track on Java Interview Hub.

• What is Java?
• What are the features of Java?
• What is JVM and why is it important?
• What is the difference between JDK, JRE, and JVM?
• What is the use of the public static void main(String[] args) method?
• Explain the concept of Object-Oriented Programming in Java?
• What is inheritance in Java?
• What is polymorphism in Java?
• Explain encapsulation with an example in Java.
• What is an interface in Java?
• Explain the concept of an abstract class.
• What are constructors in Java?
• What is method overloading?
• What is method overriding?
• What is a package in Java?
• Explain the final keyword in Java.
• What are Java Exceptions?
• What is the difference between checked and unchecked exceptions?
• What is the static keyword used for in Java?
• What is a thread in Java?
• Explain the difference between == and .equals() in Java.
• What is garbage collection in Java?
• What is the Collections Framework in Java?
• Explain synchronized keyword in Java.
• What are generics in Java?
• What is the use of 'this' keyword in Java?
• What is Enum in Java?
• What are threads?
• What is multithreading?
• Explain volatile keyword in Java.