Chain of Responsibility design pattern Demo

  Function: leave approval process, leave within three days, the Director for approval; leave for 3-10 days, manager approval; leave more than 10 days, the general manager for approval.

1. Define a leave request LeaveRequest class.

. 1  public  class LeaveRequest {
 2          Private String name; // leave name 
. 3          Private  int Days; // leave days 
. 4          Private String reason; // leave reasons 
. 5  
. 6          public LeaveRequest (name String, int Days, String reason) {
 . 7              the this = .name name;
 . 8              the this .days = Days;
 . 9              the this .reason = reason;
 10          }
 . 11  
12 is          public String getName () {
13             return name;
14         }
15 
16         public void setName(String name) {
17             this.name = name;
18         }
19 
20         public int getDays() {
21             return days;
22         }
23 
24         public void setDays(int days) {
25             this.days = days;
26         }
27 
28         public String getReason() {
29             return reason;
30         }
31 
32         public void setReason(String reason) {
33             this.reason = reason;
34         }
35     }

2. Define a Leader abstract class, there is a property nextLeader superiors, there is a request to leave the handleRequest method () process

 1 public abstract class Leader {
 2     protected String name;
 3     protected Leader nextLeader;//责任链后期对象
 4     public Leader(){
 5 
 6     }
 7 
 8     public Leader(String name){
 9         super();
10         this.name=name;
11     }
12 
13     public void setNextLeader(Leader nextLeader) {
14         this.nextLeader = nextLeader;
15     }
16 
17      // process the core service request method 
18 is      public  abstract  void the handleRequest (LeaveRequest leaveRequest);
 . 19 }

3. Define a Director of the subclass, override the parent class method, director of treatment within three days, more than three days, to superiors

public  class Director the extends Leader { 

    public Director (String name) {
         Super (name); 
    } 
    @Override 
    public  void the handleRequest (LeaveRequest leaveRequest) {
         IF (leaveRequest.getDays () <. 3 ) {
             // process 
            System.out.println ( " Director approved by ... " ); 
        } the else {
             // not treated, to the next process 
            the this .nextLeader.handleRequest (leaveRequest); 
        } 
    } 
}

4. Similarly, Manager class only 3-10 days leave processing.

 1 public class Manager extends Leader{
 2     public Manager(String name){
 3         super(name);
 4     }
 5     @Override
 6     public void handleRequest(LeaveRequest leaveRequest) {
 7         if (leaveRequest.getDays()>3&&leaveRequest.getDays()<=10){
 8             System.out.println("经理审批成功");
 9         }else {
10             this.nextLeader.handleRequest(leaveRequest);
11         }
12     }
13 }

5.GeneralMmanger class above processes leave 10 days

. 1  public  class include GeneralManager the extends Leader {
 2      public include GeneralManager (String name) {
 . 3          Super (name);
 . 4      }
 . 5      @Override
 . 6      public  void the handleRequest (LeaveRequest leaveRequest) {
 . 7          IF (leaveRequest.getDays () <30 ) {
 . 8              the System. out.println ( "approved by the general manager ..." );
 9          } the else {
 10              System.out.println (leaveRequest.getName () + ":! want to quit it." );
 11          }
 12     }
13 }

6. Test Class Code

 1 public class Main {
 2 
 3     public static void main(String[] args) {
 4         Director director = new Director("主任");
 5         Manager manager = new Manager("经理");
 6         GeneralManager generalManager = new GeneralManager("总经理");
 7         director.setNextLeader(manager);
 8         manager.setNextLeader(generalManager);
 9         LeaveRequest leaveRequest = new LeaveRequest("洪昶", 1, "面试");
10         director.handleRequest(leaveRequest);
11     }
12 }

7. The results show