如何用 Java 创建自定义类?

原文:https://www . geesforgeks . org/如何在 java 中创建自定义类/

是对象的集合。类不是真实世界的实体,它只是模板、原型或蓝图。类不占用内存。我们可以根据自己的选择编写一个自定义类,用于说明目的。下面的程序中显示了一个示例作为助手类。

示例:

Java 语言(一种计算机语言,尤用于创建网站)

// Java Program to Creating our Own Custom Class

// Importing input output classes
import java.io.*;

// Class 1
// Helper class
class Employee {

    // Member variables of this class

    // first attribute
    int id;
    // second attribute
    int salary;
    // third attribute
    String name;

    // Member function of this class

    // Method 1
    public void printDetails()
    {
        // Print and display commands
        System.out.println("My id is " + id);
        System.out.println("This is my name " + name);
    }

    // Method 2
    public int getSalary()
    {

        // Simply returning the salary
        return salary;
    }
}

// Class 2
// Main class
class Custom {

    // Main driver method
    public static void main(String[] args)
    {

        // Display message only
        System.out.println("This is the custom class");

        // Creating object of custom class in the main()
        // method Instantiating a new Employee object
        Employee harry = new Employee();

        // Again creating object of custom class and
        // instantiating a new Employee object
        Employee robin = new Employee();

        // Initializing values for first object created
        // above
        harry.id = 23;
        harry.salary = 100000;
        harry.name = "Ritu bhatiya";

        // Initializing values for second object created
        // above
        robin.id = 25;
        robin.salary = 150000;
        robin.name = "Amit thripathi";

        // Printing object attributes by
        // calling the method as defined in our class
        harry.printDetails();
        robin.printDetails();

        // Calling the method again of our class and
        // storing it in a variable
        int salary = robin.getSalary();

        // Print and display the above salary
        System.out.println("Salary of robin : " + salary
                           + "{content}quot;);

        System.out.println("ID : " + harry.id);
    }
}

Output

This is the custom class
My id is 23
This is my name Ritu bhatiya
My id is 25
This is my name Amit thripathi
Salary of robin : 150000$
ID : 23