What is the difference between default and protected in Java?

Default and protected are used as access specifiers in java.

If you don't use any specifier, it is treated as default . The default modifier is accessible only within package.

Example of default access modifier

In this example, we have created two packages pack and mypack. We are accessing the A class from outside its package, since A class is not public, so it cannot be accessed from outside the package.

//save by A.java

package pack;

class A

{

void msg( )

{

System.out.println("Hello");}

}

//save by B.java

package mypack;

import pack.*;

class B{

public static void main(String args[]){

A obj = new A();//Compile Time Error

obj.msg();//Compile Time Error

}

}

In the above example, the scope of class A and its method msg() is default so it cannot be accessed from outside the package.

The protected access modifier is accessible within package and outside the package but through inheritance only.

The protected access modifier can be applied on the data member, method and constructor. It can't be applied on the class.

Example of protected access modifier

In this example, we have created the two packages pack and mypack. The A class of pack package is public, so can be accessed from outside the package. But msg method of this package is declared as protected, so it can be accessed from outside the class only through inheritance.

//save by A.java

package pack;

public class A{

protected void msg(){System.out.println("Hello");}

}

//save by B.java

package mypack;

import pack.*;

class B extends A{

public static void main(String args[]){

B obj = new B();

obj.msg();

}

}

Output : Hello