TÀI LIỆU HAY - CHIA SẺ KHÓA HỌC MIỄN PHÍ

Java Interview Questions You Need To Know

If you are looking for a job in the Java development field, then there is a high chance that you will have to go through an interview process. Interviews can be nerve-wracking especially if you are not sure what questions you might be asked. However, preparation is the key to success. Here are some Java interview questions that you should know in order to increase your chances of getting hired.

1. What is Java?

Java is an object-oriented programming language used to develop software applications. It was created in 1995 by James Gosling and his team of developers at Sun Microsystems. Java is the most popular programming language in the world and is used to build server-side applications, games, mobile applications and many other software programs.

2. What is the difference between runtime and compile time?

Runtime errors occur during the execution of the program while compile-time errors occur during the compilation of code. Compile-time errors are easy to fix while runtime errors may require some debugging.

3. What is JVM?

JVM stands for Java Virtual Machine. It is the runtime environment for Java code. It executes Java code by translating it into machine code. JVM has various components such as Classloader, Execution Engine, and Garbage Collector.

4. What is the difference between overloading and overriding?

Overloading occurs when two or more methods in the same class have the same name but different parameters. Overriding occurs when a method in a subclass has the same name, parameters, and return type as a method in its superclass.

5. What is a constructor?

A constructor is a method that is used to initialize an object. It has the same name as the class and does not have a return type. A constructor is called when an object of a class is created.

6. What is the difference between abstract class and interface?

An abstract class can have non-abstract methods while an interface can only have abstract methods. An abstract class can be extended by other classes while an interface can be implemented by any class.

7. What is a package?

A package is a group of related classes, interfaces, and sub-packages. It provides a way to organize code and avoid naming conflicts.

8. What is a static method?

A static method is a method that belongs to the class and not the object of that class. It can be called without creating an object of the class.

9. What is a final keyword?

A final keyword is used to define a constant variable that cannot be changed. It can also be used to create a method that cannot be overridden.

10. What is a synchronized keyword?

The synchronized keyword is used to control access to shared resources in a multi-threaded environment. It ensures that only one thread can access the resource at a time.

In conclusion, these are some of the basic Java interview questions that you should know. Preparing for an interview can be stressful, but with knowledge and practice of these concepts, you can increase your chances of success. Good luck!