TCS Java Developer Interview Questions and Answers for Freshers

Compile time polymorphism is achieved through method overloading, while runtime polymorphism is achieved through method overriding.

• Compile time polymorphism is also known as static polymorphism.

• It is achieved by having multiple methods in the same class with the same name but different parameters.

• Example: method overloading in Java.

• Runtime polymorphism is also known as dynamic polymorphism.

• It is achieved by having a method in a superclass and a method with the same signature ...read more

Exceptions in Spring Boot can be handled using try-catch blocks, @ExceptionHandler annotation, and global exception handling.

• Use try-catch blocks to handle exceptions within a specific method.

• Use @ExceptionHandler annotation to handle exceptions at the controller level.

• Implement a global exception handler using @ControllerAdvice and @ExceptionHandler annotations.

• Customize error responses using ResponseEntityExceptionHandler.

• Use @ResponseStatus annotation to specify the HTTP s...read more

A classLoader is a part of the Java Runtime Environment that dynamically loads Java classes into the Java Virtual Machine.

• ClassLoader is responsible for loading classes at runtime in Java.

• It follows a delegation hierarchy to search for classes.

• There are different types of class loaders like Bootstrap, Extension, and System class loaders.

• Custom class loaders can be created to load classes from different sources like network or database.

Polymorphism is the ability of an object to take on multiple forms.

• Polymorphism allows objects of different classes to be treated as objects of a common superclass.

• There are two types of polymorphism: compile-time (method overloading) and runtime (method overriding).

• Example: Animal superclass with Dog and Cat subclasses, both overriding the makeSound() method.

Constructor is a special method that is used to initialize objects in Java.

• Constructor has the same name as the class name

• It does not have a return type

• It can be overloaded

• It is called automatically when an object is created

• Example: public class Car { public Car() { // constructor code here } }