Curriculum design patterns Design patterns succinctly 3-2 opening and closing the principle of coding

1 The course explains

2 code coding

 

1 The course explains

2 code coding

2.1 base class

Test categories:

Package com.geely.design.principle.openclose; 

public  class TestJavaCourse {
     public  static  void main (String [] args) { 
        Icourse icourse = new new JavaCourse (96, "Java Development Guide", 298.00 ); 
        System.out.println ( " Buy course number: "+ icourse.getCourseId () +" ; course name: "+ icourse.getCourseName () +" ; the price of the course: "+ icourse.getCourcePrice ()); 
    } 
}

 

Entity classes:

package com.geely.design.principle.openclose;

public class JavaCourse implements Icourse {
    private Integer courseId;
    private String courseName;
    private Double coursePrice;

    public JavaCourse(Integer courseId, String courseName, Double coursePrice) {
        this.courseId = courseId;
        this.courseName = courseName;
        this.coursePrice = coursePrice;
    }

    @Override
    public Integer getCourseId() {
        return this.courseId;
    }

    @Override
    public String getCourseName() {
        return this.courseName;
    }

    @Override
    public Double getCourcePrice() {
        return this.coursePrice;
    }
}

 

interface:

Package Penalty for com.geely.design.principle.openclose; 

public  interface Icourse { 
    Integer getCourseId (); // get course ID 
    String getCourseName (); // get the course name 
    Double getCourcePrice (); // get course price 

}

 

Print log:

Buy Course number: 96; course name: java development course; course price: 298.0 

Process Finished with Exit code 0