Usage of default in java

The default keyword in Java is used to define the default implementation of a class, interface or method. Its main uses include: defining default methods for classes or interfaces, adding new behaviors without modifying inheritance or implementation classes; The method defines a default implementation, which is used when the method is overridden; provides a default implementation of a method in the interface so that the implementation class can choose to override or use the default implementation.

Usage of default in Java

Get straight to the point

default is in Used in Java to define the default implementation of a class, interface, or method.

Detailed explanation

Classes and interfaces

##default keyword can be used to define the default for a class or interface Methods, which can be overridden by inherited classes or classes that implement the interface.
• Default methods provide a way to add new behavior without modifying the inherited or implementing class.

Method

#default keyword can also be used to define default implementations of methods, which can be used when the method is overridden.
• The default method allows adding new behavior to the inherited class without modifying the parent class.

Syntax

Classes and interfaces:

public interface MyInterface {
    default void myMethod() {
        // Default implementation
    }
}

Methods:

public class MyParentClass {
    public void myMethod() {
        // Default implementation
    }
}

public class MyChildClass extends MyParentClass {
    @Override
    public void myMethod() {
        // Overridden implementation
    }
}

Access Level

Default methods and members have the same access level as the class or interface in which they are defined, unless otherwise declared.

When to use default

When you need to add new behavior to an existing class or interface, but do not want to force inheritance or implementation classes to override this behavior hour.
• When you wish to provide a default implementation of a method so that this implementation is used when there is no override.
• When you wish to provide a default implementation of a method in an interface so that implementing classes can choose to override or use the default implementation.

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