职责链模式调用

public class chainHandlerDemo {
    public static void main(String[] args) {
        PipleLineDemo pipleLineDemo = new PipleLineDemo();
        pipleLineDemo.addLast(new Handler1());
        pipleLineDemo.addLast(new Handler2());

        pipleLineDemo.processStart("I am Head");
    }
}

interface AbstractHandler {
    void handler(ChainHandlerContext chainHandlerContext, Object args);
}

class Handler1 implements AbstractHandler {

    @Override
    public void handler(ChainHandlerContext chainHandlerContext, Object args) {
        String args2 = args + "--->I am Handler1";
        System.out.println(args2);
        chainHandlerContext.doNext(args2);
    }
}

class PipleLineDemo {
    static ChainHandlerContext context = new ChainHandlerContext();

    void addLast(AbstractHandler handler) {
        while (context.next != null) {
            context = context.next;
        }
        context.next = new ChainHandlerContext();
        context.next.handler = handler;
    }

    public PipleLineDemo() {
        context.handler = new AbstractHandler() {
            @Override
            public void handler(ChainHandlerContext chainHandlerContext, Object args) {
                System.out.println(args);
            }
        };
    }

    /**
     * 启动任务入口
     */
    void processStart(Object args) {
        context.doHandler(args);
    }
}

class Handler2 implements AbstractHandler {

    @Override
    public void handler(ChainHandlerContext chainHandlerContext, Object args) {
        String args2 = args + "--->I am Handler2";
        System.out.println(args2);
        chainHandlerContext.doNext(args2);
    }
}

class ChainHandlerContext {
    ChainHandlerContext next;
    AbstractHandler handler;

    void doHandler(Object args) {
        handler.handler(this, args);
    }

    void doNext(Object args) {
        if (next != null) {
            next.doHandler(args);
        }
        else{
            System.out.println(args+"--->I am tail, no any other handler");
        }
    }

}

测试结果