Access Modifier in Java

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 In Java, access modifiers are keywords used to define the scope or accessibility of variables, methods, and classes. There are four types of access modifiers in Java:

  1. Public: Public access modifier makes the class, method, or variable accessible from any class or package.

  2. Private: Private access modifier makes the class, method, or variable accessible only within the same class.

  3. Protected: Protected access modifier makes the class, method, or variable accessible within the same class, any subclass, and any package.

  4. Default or Package-private: If no access modifier is specified, then it is considered as default or package-private. The class, method, or variable is accessible within the same class and any other class within the same package.

Access modifiers are used to encapsulate the implementation details and to provide proper access control to the methods and variables. By restricting access to certain methods and variables, we can prevent them from being modified or accessed by unintended classes or methods.

e are some examples of each access specifier in Java:

  1. Public access specifier:
csharp
public class MyClass {
    public int publicVar = 10;
    public void publicMethod() {
        // method implementation
    }
}

In this example, the class and its members are accessible from any other class or package.

  1. Private access specifier:
csharp
public class MyClass {
    private int privateVar = 10;
    private void privateMethod() {
        // method implementation
    }
}

In this example, the class members are only accessible within the same class.

  1. Protected access specifier:
csharp
public class MyClass {
    protected int protectedVar = 10;
    protected void protectedMethod() {
        // method implementation
    }
}

In this example, the class members are accessible within the same class, any subclass, and any package.

  1. Default or Package-private access specifier:
csharp
class MyClass {
    int defaultVar = 10;
    void defaultMethod() {
        // method implementation
    }
}

In this example, the class members are only accessible within the same class and any other class within the same package. Note that the access specifier keyword is omitted here, and this is how we define package-private access.


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