Public Access Modifiers in Java
Introduction
Public access modifier is a keyword in the Java programming language that limits the access of a particular type, field, method, or constructor to other classes and code. The public access modifier allows classes, fields, methods, and constructors to be visible to all other classes in the same package and to all classes in other packages. The public access modifier is one of the four access modifiers available in Java. The other three are private, protected, and default. The public access modifier in Java programs is the most widely used access modifier.
Overview
The public access modifier is one of four in the Java programming language. The other three are private, protected, and default. The public access modifier gives other classes or codes access to a particular type, field, method, or constructor. The public access modifier is the most widely used in Java.
The public access modifier allows classes, fields, methods, and constructors to be visible to all other classes in the same package and to all classes in other packages. It is important to note that a class, field, method, or constructor with the public access modifier can be accessed from any other class, regardless of the package.
Syntax
The syntax for the public access modifier is as follows:
public class ClassName {
//class body
}
public int fieldName;
public void methodName() {
//method body
}
public ClassName(int parameter) {
//constructor body
}
The public access modifier is a keyword before the class, field, method, or constructor. For example, the public access modifier is used before the class name when declaring a class. It is also used before the field, method, or constructor is declared.
How to use the Public access modifier
The public access modifier has several uses in Java programs. It is often used to make classes, fields, methods, and constructors visible to other classes and codes. The public access modifier allows classes, fields, methods, and constructors to be visible to all other classes in the same package and to all classes in other packages.
The public access modifier is also used to make classes, fields, methods, and constructors accessible outside the package. This is useful when creating APIs or libraries that need to be accessed from other classes or packages.
The public access modifier is also used to make classes, fields, methods, and constructors accessible from different parts of the same program. This is useful when different parts of a program need to access the same data or functionality.
Advantages
The public access modifier has several advantages in Java programs. The most obvious advantage is that it allows classes, fields, methods, and constructors to be visible to all other classes in the same package and to all classes in other packages. This is useful when creating APIs or libraries that need to be accessed from other classes or packages.
The public access modifier makes classes, fields, methods, and constructors accessible outside the package. This is useful when creating APIs or libraries that need to be accessed from other classes or packages.
The public access modifier also makes classes, fields, methods, and constructors accessible from different parts of the same program. This is useful when different parts of a program need to access the same data or functionality.
Disadvantages
The public access modifier has some disadvantages in Java programs. The most obvious disadvantage is that it makes classes, fields, methods, and constructors accessible from all other classes in the same package and from all classes in other packages. This can lead to security issues as anyone can access the classes, fields, methods, and constructors with the public access modifier.
Another disadvantage of the public access modifier is that it can lead to code that is difficult to maintain and debug. When classes, fields, methods, and constructors are accessible from all other classes, it can be difficult to track down the source of an issue.
Program
public class PublicAccessModifierDemo {
public int num1 = 10;
public int num2 = 20;
public void add() {
System.out.println("The addition of two numbers is : " + (num1 + num2));
}
public static void main(String args[]) {
PublicAccessModifierDemo obj = new PublicAccessModifierDemo();
obj.add();
}
}
Output
The addition of two numbers is: 30
Conclusion
The public access modifier is one of the four access modifiers available in Java. It is the most widely used access modifier and allows classes, fields, methods, and constructors to be visible to all other classes in the same package and to all classes in other packages. The public access modifier is useful for creating APIs or libraries that need to be accessed from other classes or packages. However, it can also lead to security issues and make code difficult to maintain and debug.