MVC Pattern代表模型 - 视图 - 控制器模式.此模式用于分离应用程序的问题.
模型 - 模型表示对象或JAVA POJO携带数据.如果控制器的数据发生变化,它也可以有更新控制器的逻辑.
查看 - 视图表示模型包含的数据的可视化.
控制器 - 控制器同时作用于模型和视图.它控制数据流到模型对象,并在数据发生变化时更新视图.它使视图和模型分开.
我们将创建一个学生对象充当模型. StudentView 将是一个视图类,可以在控制台上打印学生详细信息, StudentController 是负责存储数据的控制器类学生对象并相应地更新视图 StudentView .
MVCPatternDemo ,我们的演示类,将使用 StudentController 演示使用MVC模式.
创建模型.
Student.java
public class Student { private String rollNo; private String name; public String getRollNo() { return rollNo; } public void setRollNo(String rollNo) { this.rollNo = rollNo; } public String getName() { return name; } public void setName(String name) { this.name = name; } }
创建视图.
StudentView.java
public class StudentView { public void printStudentDetails(String studentName, String studentRollNo){ System.out.println("Student: "); System.out.println("Name: " + studentName); System.out.println("Roll No: " + studentRollNo); } }
创建控制器.
StudentController.java
public class StudentController { private Student model; private StudentView view; public StudentController(Student model, StudentView view){ this.model = model; this.view = view; } public void setStudentName(String name){ model.setName(name); } public String getStudentName(){ return model.getName(); } public void setStudentRollNo(String rollNo){ model.setRollNo(rollNo); } public String getStudentRollNo(){ return model.getRollNo(); } public void updateView(){ view.printStudentDetails(model.getName(), model.getRollNo()); } }
使用 StudentController 演示MVC设计模式用法的方法.
MVCPatternDemo.java
public class MVCPatternDemo { public static void main(String[] args) { //fetch student record based on his roll no from the database Student model = retriveStudentFromDatabase(); //Create a view : to write student details on console StudentView view = new StudentView(); StudentController controller = new StudentController(model, view); controller.updateView(); //update model data controller.setStudentName("John"); controller.updateView(); } private static Student retriveStudentFromDatabase(){ Student student = new Student(); student.setName("Robert"); student.setRollNo("10"); return student; } }
验证输出.
Student: Name: Robert Roll No: 10 Student: Name: John Roll No: 10