List和Map的链式添加

package com.wing.ai.cloud.system.modular.proxy;

import java.util.ArrayList;
import java.util.Collection;

/**
 * @ProjectName: ai-cloud
 * @Package: com.wing.ai.cloud.system.modular.proxy
 * @ClassName: ArrayListProxy
 * @Author: heluwei
 * @Description: ArrayList代理类,用来实现链式添加
 * @Date: 2020/4/14 14:01
 * @Version: 1.0
 */
public class ArrayListProxy<E> extends ArrayList<E> {

    /**
     * 重写ArrayList的所有构造函数---start
     */
    public ArrayListProxy(Collection<? extends E> c) {
        super(c);
    }

    public ArrayListProxy(int initialCapacity) {
        super(initialCapacity);
    }


    public ArrayListProxy() {
        super();
    }
    //重写ArrayList的所有构造函数---end

    /**
     * 对 ArrayList 的 add() 的方法进行封转返回  ArrayListProxy 来实现 链式添加
     * @param e
     * @return
     */
    public ArrayListProxy addObject(E e){
        if(this.add(e)){
            return this;
        }
        throw new ArrayStoreException("ArrayListProxy add element fail!");
    }

    /**
     * 对 ArrayList 的 addAll() 的方法进行封转返回  ArrayListProxy 来实现 链式添加
     */
    public ArrayListProxy addAllObject(Collection<? extends E> e){
        if(this.addAll(e)){
            return this;
        }
        throw new ArrayStoreException("ArrayListProxy addAll element fail!");
    }
}

使用:

package com.wing.mall.base.test;

import java.util.ArrayList;
import java.util.List;

/**
 * @ProjectName: baby
 * @Package: com.wing.mall.base.test
 * @ClassName: AddAllList
 * @Author: heluwei
 * @Description: 测试合并两个list
 * @Date: 2020/4/14 14:47
 * @Version: 1.0
 */
public class AddAllList {
    public static void main(String[] args) {
        ArrayListProxy<String> listA = new ArrayListProxy<>();
        //链式添加元素
        listA.addObject("A_a").addObject("A_b");
        ArrayListProxy<String> listB = new ArrayListProxy<>();
        listB.addObject("B_a").addObject("B_b");
        ArrayListProxy<String> list = new ArrayListProxy<>();
        //链式合并元素
        list.addAllObject(listA).addAllObject(listB);
        list.forEach(s -> {
            System.out.println(s);
        });
    }
}

Map:

package com.wing.ai.cloud.system.modular.proxy;

/**
 * @ProjectName: ai-cloud
 * @Package: com.wing.ai.cloud.system.modular.proxy
 * @ClassName: HashMapProxy
 * @Author: heluwei
 * @Description: HashMap 的代理类 实现链式添加元素
 * @Date: 2020/4/14 14:03
 * @Version: 1.0
 */

import java.util.HashMap;
import java.util.Map;

/**
 *HashMap 的代理类 实现链式添加元素
 * example:  HashMapProxy hashMapProxy   = new HashMapProxy();
 *            hashMapProxy.putObject("a","b").putObject("c","d");
 * @param <K>
 * @param <V>
 */
public class HashMapProxy<K,V> extends HashMap<K,V> {

    /**
     * @Description 重写HashMap的所有构造函数---start
     * @Date 2020/4/14 14:03
     */
    public HashMapProxy(int initialCapacity) {
        super(initialCapacity);
    }

    public HashMapProxy() {
        super();
    }

    public HashMapProxy(Map<? extends K, ? extends V> m) {
        super(m);
    }


    public HashMapProxy(int initialCapacity, float loadFactor) {
        super(initialCapacity,loadFactor);
    }
    //重写HashMap的所有构造函数---end

    /**
     * 对 HashMap 的 put() 的方法进行封转返回  HashMapProxy 来实现 链式添加
     * @param key
     * @param value
     * @return
     */
    public HashMapProxy putObject(K key,V value){
        this.put(key, value);
        return this;
    }

}

 测试:

package com.wing.mall.base.test;

/**
 * @ProjectName: baby
 * @Package: com.wing.mall.base.test
 * @ClassName: TestLianShiMap
 * @Author: heluwei
 * @Description: 链式使用Map
 * @Date: 2020/4/14 15:32
 * @Version: 1.0
 */
public class TestLianShiMap {
    public static void main(String[] args) {
        HashMapProxy<Object, Object> mapProxy = new HashMapProxy<>();
        mapProxy.putObject("a", "a")
                .putObject("b","b");
        mapProxy.forEach((k,v) ->{
            System.out.println(k+":"+v);
        });
    }
}
原文地址:https://www.cnblogs.com/bulrush/p/12698344.html