class keyword in Java

The class keyword is used to declare a new Java class, which is a collection of related variables and/or methods.

Classes are the basic building blocks of object−oriented programming.

A class typically represents some real−world entity such as a geometric Shape or a Person.

A class is a template for an object. Every object is an instance of a class.

To use a class, you instantiate an object of the class, typically with the new operator, then call the methods to access the features of the class.

Class will be defined with access specifier as either public or default only.

We can’t make class as private or protected(can be done only for inner classes)

Example 1

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public class Rectangle
 {
 
       float width;
 
       float height;
 
       public Rectangle(float w, float h){
 
            width = w;
 
            height = h;
       }
 
       public float getWidth(){
 
            return width;
       }
 
       public float getHeight(){ 
            return height;
       }
}
public class Rectangle
 {

       float width;

       float height;

       public Rectangle(float w, float h){

            width = w;

            height = h;
       }

       public float getWidth(){

            return width;
       }

       public float getHeight(){ 
            return height;
       }
}

Example 2

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public class Person
{
 
      String name;
 
      int age;
 
      public int getAge() {
 
           return age;
      }
 
      public String getName() {
 
          return name;
      }
 
 
      public void setName(String name){
          this.name = name;
      }
 
      public void setAge(String age) {
          this.age = age;
      }
 
}
public class Person
{

      String name;

      int age;

      public int getAge() {

           return age;
      }

      public String getName() {

          return name;
      }


      public void setName(String name){
          this.name = name;
      }

      public void setAge(String age) {
          this.age = age;
      }

}

About the Author

Karibasappa G C (KB)
Founder of javainsimpleway.com
I love Java and open source technologies and very much passionate about software development.
I like to share my knowledge with others especially on technology 🙂
I have given all the examples as simple as possible to understand for the beginners.
All the code posted on my blog is developed,compiled and tested in my development environment.
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