In this blog, we are going to learn about Access Specifiers in Java.

Access Specifiers in Java

1. Public: Fields, methods and constructors declared public (least restrictive) within a public class are visible to any class in the Java program, whether these classes are in the same package or in another package.

   • Public Specifiers achieves the highest level of accessibility.

2. Protected: Fields, methods and constructors declared protected in a superclass can be accessed only by classes in same package as well as by subclasses in other packages.

   • Classes in the same package can also access protected fields, methods and constructors as well, even if they are not a subclass of the protected member’s class.
   • The protected access modifier can be applied on the data member, method and constructor. It can’t be applied on the class/interface. Like default case+can access subclass of different package
   • Methods and fields declared as protected can only be accessed by the subclasses in other package or any class within the package of the protected members’ class.

3. Default: Default modifier is accessible only within package.

   • When you don’t set access specifier for the element, it will follow the default accessibility level.
   • There is no default specifier keyword.
   • Can access class, method, or field which belongs to same package,but not from outside this package.
   • Classes, variables, and methods can be default accessed(accessible only by classes in same package).

4. Private: Cannot be accesses by anywhere outside the enclosing class.

   • Has lowest level of accessibility and not visible within subclasses and are not inherited by subclasses(within package and in different package).
   • Helps to achieve encapsulation and hide data from the outside world.
   • Here, 2 classes A and Simple are defined. A class contains private data member and private method.As we are accessing these private members from outside class, so there is compile time error.
   • The private access modifiers is accessible only within the class.

//example of private access modifier
class A{  
	private int data=40;     
    private void msg()
 {
	System.out.println("Hello java");
 }  
 } 

public class Simple{   
	public static void main(String args[])
	{     
        A obj=new A();    
	System.out.println(obj.data); // Compile Time Error  
   obj.msg(); // Compile Time Error  
   } }