java设计模式--责任链模式

责任链模式：将能够处理同一类请求的对象连成一条链，如果不能处理则传递给链上的下一个对象。

//请假对象
public class QingjiaRequest {
    
    private String name;
    
    private int days;
    
    private String reason;

    public QingjiaRequest(String name, int days, String reason) {
        this.name = name;
        this.days = days;
        this.reason = reason;
    }

    public String getName() {
        return name;
    }

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

    public int getDays() {
        return days;
    }

    public void setDays(int days) {
        this.days = days;
    }

    public String getReason() {
        return reason;
    }

    public void setReason(String reason) {
        this.reason = reason;
    }

}

//抽象类
public abstract class Leader {
    
    String name;
    
    Leader nextLeader;

    public Leader(String name) {
        this.name = name;
    }

    public void setNextLeader(Leader nextLeader) {
        this.nextLeader = nextLeader;
    }
    
    //设置责任链的处理对象（核心）
    public abstract void handleRequest(QingjiaRequest qingjiaRequest);

}

//主任
public class Zhuren extends Leader{

    public Zhuren(String name){
        super(name);
    }
    
    
    public void handleRequest(QingjiaRequest qingjiaRequest) {
        if(qingjiaRequest.getDays()<3){
            System.out.println("员工请假小于3天");
            System.out.println("审批通过");
        }else{
            if(this.nextLeader!=null){
                this.nextLeader.handleRequest(qingjiaRequest);
            }
        }
        
        
    }

}

//经理
public class Manager extends Leader{

    public Manager(String name){
        super(name);
    }
    
    
    public void handleRequest(QingjiaRequest qingjiaRequest) {
        if(qingjiaRequest.getDays()<10&&qingjiaRequest.getDays()>3){
            System.out.println("经理审批通过");
        }else{
             //经理处理后的逻辑
        }
        
        
    }

}

public static void main(String[] args) {
        
        QingjiaRequest qingjiaRequest = new QingjiaRequest("张三", 2, "请假");
        //QingjiaRequest qingjiaRequest1 = new QingjiaRequest("张三", 5, "请假");
        Leader a = new Zhuren("张主任");
        Leader b = new Manager("王经理");
        //可以用一个容器对象责任链对象进行一些封装
        a.setNextLeader(b);
        //开始请假
        a.handleRequest(qingjiaRequest);
        
    }

应用场景：try catch,javascript 冒泡，servlet filter,struts2 拦截器