责任链模式进行参数校验

定义模板handler

package com.zj.study.xx;
​
/**
 * @author Zpain
 * @date 2023/6/25 16:08
 */
public abstract class Handler<T> {
​
    protected Handler<T> next;
​
    public void setNext(Handler<T> next) {
        this.next = next;
    }
​
    /**
     * 执行任务
     * @param a
     */
    public abstract void doHandler(T a);
​
    public static class Builder<T> {
        private Handler<T> head;
        private Handler<T> tail;
​
        public Builder<T> addHandler(Handler<T> handler) {
            if (this.head == null) {
                this.head = handler;
                this.tail = handler;
                return this;
            }
            this.tail.setNext(handler);
            this.tail = handler;
            return this;
        }
​
        public Handler<T> build() {
            return this.head;
        }
    }
​
}
​

定义执行计划

package com.zj.study.xx;
​
/**
 * @author zhangjun
 * @date 2023/6/25 16:14
 */
public class Ahandler<T> extends Handler<T> {
    @Override
    public void doHandler(T a) {
        if (!"a".equals(a)) {
            System.out.println("a error");
            return;
        }
        if (null != next) {
            next.doHandler(a);
        }
    }
}
​

package com.zj.study.xx;
​
/**
 * @author zhangjun
 * @date 2023/6/25 16:14
 */
public class Bhandler<T> extends Handler<T> {
    @Override
    public void doHandler(T b) {
        if (!"b".equals(b)) {
            System.out.println("b error");
            return;
        }
        if (null != next) {
            next.doHandler(b);
        }
    }
}
​

package com.zj.study.xx;
​
/**
 * @author zhangjun
 * @date 2023/6/25 16:14
 */
public class Chandler<T> extends Handler<T> {
    @Override
    public void doHandler(T c) {
        if (!"a".equals(c)) {
            System.out.println("c error");
            return;
        }
        if (null != next) {
            next.doHandler(c);
        }
    }
}
​

package com.zj.study.xx;
​
/**
 * @author zhangjun
 * @date 2023/6/25 16:14
 */
public class Dhandler<T> extends Handler<T> {
    @Override
    public void doHandler(T d) {
        System.out.println("ok");
    }
}
​

最终执行

   Handler.Builder<String> builder = new Handler.Builder<>();
        Handler.Builder<String> builder1 = builder.addHandler(new Ahandler<String>())
                .addHandler(new Bhandler<String>())
                .addHandler(new Chandler<String>())
                .addHandler(new Dhandler<String>());
        builder1.build().doHandler("a");

注入Spring

package com.zj.study.yyy;
​
import com.zj.study.A;
import com.zj.study.B;
​
/**
 * @author Zpain
 * @date 2023/6/25 16:08
 */
public interface Handler2 {
    /**
     * 执行任务
     *
     * @param b
     */
    B doHandler(B b);
​
​
}
​
@AllArgsConstructor
@NoArgsConstructor
@Data
public class B {
    private int id;
    private int num;
}

定义执行计划

package com.zj.study.yyy;
​
import com.zj.study.B;
import org.springframework.stereotype.Service;
​
/**
 * @author Zpain
 * @date 2023/6/25 16:53
 */
@Service
public class AaHandler implements Handler2 {
​
    /**
     * 执行任务
     *
     * @param b
     */
    @Override
    public B doHandler(B b) {
        if (b.getId() < 10) {
            throw new RuntimeException("id error");
        }
        return b;
    }
}
​

package com.zj.study.yyy;
​
import com.zj.study.B;
import org.springframework.stereotype.Service;
​
/**
 * @author Zpain
 * @date 2023/6/25 16:53
 */
@Service
public class BbHandler implements Handler2 {
​
    /**
     * 执行任务
     *
     * @param b
     */
    @Override
    public B doHandler(B b) {
        if (b.getNum() < 10) {
            throw new RuntimeException("num error");
        }
        return b;
    }
}
​

package com.zj.study.yyy;
​
import com.zj.study.B;
import org.springframework.stereotype.Service;
​
/**
 * @author Zpain
 * @date 2023/6/25 16:53
 */
@Service
public class CcHandler implements Handler2 {
​
    /**
     * 执行任务
     *
     * @param b
     */
    @Override
    public B doHandler(B b) {
        System.out.println("ok");
        return b;
    }
}
​

注入到Spring中

package com.zj.study.yyy;
​
import com.zj.study.B;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
​
import java.util.ArrayList;
import java.util.List;
​
/**
 * @author Zpain
 * @date 2023/6/25 17:15
 */
@Component
public class HandlerAdaptor {
    @Autowired
    private List<Handler2> list;
​
    public B execute(B b) {
        for (Handler2 handleIntercept : list) {
            b = handleIntercept.doHandler(b);
        }
        return b;
    }
​
}
​

最终执行

 @Autowired
    private HandlerAdaptor adaptor;
​
    @Test
    public void get3() {
        B b = new B(10, 10);
        B execute = adaptor.execute(b);
        log.info("b:{}", JSON.toJSONString(execute));
    }

如果想要执行顺序 自行定义 sort或者@Order，或者实现Ordered方式