目录

• 一、定义
• 二、普通责任链模式
• 三、异步责任链模式

一、定义

责任链模式(Chain of Responsibility Pattern)：避免将一个请求的发送者与接受者耦合在一起，让多个对象都有机会处理请求。将接受请求的对象连接成一条链，并且沿着这条链传递请求，直到有一个对象能够处理它为止。

在很多源码都有涉及，如Mybatis拦截器、Filter…

责任链模式属于行为型模式。

二、普通责任链模式

抽象处理类：AbstractProcessor

/**
 * 抽象处理类
 */
public abstract class AbstractProcessor {
    // 责任链
    private AbstractProcessor nextProcessor;

    public void setNextProcessor(AbstractProcessor nextProcessor){
        this.nextProcessor = nextProcessor;
    }

    /**
     * 链路调用
     * @param obj
     */
    public void execute(Object obj) {
        this.processor(obj);
        if (this.nextProcessor != null){
            this.nextProcessor.execute(obj);
        }
    }

    public abstract void processor(Object obj);
}

具体类：ParamsProcessor、CheckProcessor、FinalProcessor

public class ParamsProcessor extends AbstractProcessor{

    @Override
    public void processor(Object obj) {
        System.out.println("paramsProcessor>>>>>>>>>>" + obj.toString());
    }
}

public class CheckProcessor extends AbstractProcessor{

    @Override
    public void processor(Object obj) {
        System.out.println("checkProcessor>>>>>>>>>>" + obj.toString());
    }
}

public class FinalProcessor extends AbstractProcessor{

    @Override
    public void processor(Object obj) {
        System.out.println("finalProcessor>>>>>>>>>>" + obj.toString());
    }
}

测试类：ProcessorMainTest

public class ProcessorMainTest {
    public static void main(String[] args) {
        /**
         * 构建一个链路
         * paramsProcessor -> checkProcessor -> finalProcessor
         */
        AbstractProcessor paramsProcessor = new ParamsProcessor();
        AbstractProcessor checkProcessor = new CheckProcessor();
        AbstractProcessor finalProcessor = new FinalProcessor();

        paramsProcessor.setNextProcessor(checkProcessor);
        checkProcessor.setNextProcessor(finalProcessor);

        paramsProcessor.execute("Java责任链模式");
    }
}

执行结果

paramsProcessor>>>>>>>>>>Java责任链模式
checkProcessor>>>>>>>>>>Java责任链模式
finalProcessor>>>>>>>>>>Java责任链模式

三、异步责任链模式

异步责任链模式采用责任链模式、生产者消费者模式组合。

抽象处理类：AbstractAsynProcessor

/**
 * 异步责任链：采用线程、生产者消费者模式实现
 */
public abstract class AbstractAsynProcessor extends Thread {
    // 用于存放当前责任链需要处理的对象
    protected BlockingQueue<Object> queue;
    // 链路对象
    private AbstractAsynProcessor nextProcessor;

    /**
     * 执行
     *
     * @param obj
     */
    public void execute(Object obj) throws InterruptedException {
        this.processor(obj);
        if (this.nextProcessor != null) {
            this.nextProcessor.getQueue().put(obj);
        }
    }

    @Override
    public void run() {
        // 执行
        try {
            while (true) {
                // 生产者消费者
                Object obj = this.queue.take();
                execute(obj);
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    public abstract void processor(Object obj);

    public BlockingQueue<Object> getQueue() {
        return queue;
    }

    public void setNextProcessor(AbstractAsynProcessor nextProcessor) {
        this.nextProcessor = nextProcessor;
    }
}

具体类：AsynParamsProcessor、AsynCheckProcessor、AsynFinalProcessor

public class AsynParamsProcessor extends AbstractAsynProcessor {

    public AsynParamsProcessor() {
        // 初始化队列
        this.queue = new LinkedBlockingQueue<>();
    }

    @Override
    public void processor(Object obj) {
        System.out.println("asynParamsProcessor>>>>>>>>>>" + obj.toString());
    }
}

public class AsynCheckProcessor extends AbstractAsynProcessor {

    public AsynCheckProcessor(){
        this.queue = new LinkedBlockingQueue<>();
    }

    @Override
    public void processor(Object obj) {
        System.out.println("asynCheckProcessor>>>>>>>>>>" + obj.toString());
    }
}

public class AsynFinalProcessor extends AbstractAsynProcessor {

    public AsynFinalProcessor() {
        this.queue = new LinkedBlockingQueue<>();
    }

    @Override
    public void processor(Object obj) {
        System.out.println("asynFinalProcessor>>>>>>>>>>" + obj.toString());
    }
}

测试类：AsynProcessorMainTest

public class AsynProcessorMainTest {
    public static void main(String[] args) throws InterruptedException {
        /**
         * 构建一个链路
         * asynParamsProcessor -> asynCheckProcessor -> asynFinalProcessor
         */
        AbstractAsynProcessor asynParamsProcessor = new AsynParamsProcessor();
        asynParamsProcessor.start();
        AbstractAsynProcessor asynCheckProcessor = new AsynCheckProcessor();
        asynCheckProcessor.start();
        AbstractAsynProcessor asynFinalProcessor = new AsynFinalProcessor();
        asynFinalProcessor.start();

        asynParamsProcessor.setNextProcessor(asynCheckProcessor);
        asynCheckProcessor.setNextProcessor(asynFinalProcessor);

        Scanner input = new Scanner(System.in);
        while (true) {
            Thread.sleep(1000);
            System.out.print("请输入：");
            asynParamsProcessor.getQueue().put(input.next());
        }
    }
}

执行结果

请输入：Java异步责任链
asynParamsProcessor>>>>>>>>>>Java异步责任链
asynCheckProcessor>>>>>>>>>>Java异步责任链
asynFinalProcessor>>>>>>>>>>Java异步责任链

到此这篇关于Java 设计模式之责任链模式及异步责任链详解的文章就介绍到这了,更多相关Java 设计模式内容请搜索自由互联以前的文章或继续浏览下面的相关文章希望大家以后多多支持自由互联！

【本文由：http://www.1234xp.com/cdn.html 提供,感谢支持】