java8 分組計算數量和計算總數

package com.pig4cloud.pigx.admin.api.vo;

import lombok.Builder;
import lombok.Data;
import lombok.experimental.Tolerate;

import java.util.*;
import java.util.stream.Collectors;

/***
 *
 *Create by 範春宇 on 2019/12/26 17:22
 */
@Data
public class RealSkuVo implements Cloneable{

	private String realEan;
	private Integer realQty;


	public static void main(String[] args) throws CloneNotSupportedException {

		List<RealSkuVo> list = new ArrayList<>();
		RealSkuVo a = new RealSkuVo();
		RealSkuVo b1 = (RealSkuVo)a.clone();
		b1.setRealEan("asdasda");
		b1.setRealQty(1);

		RealSkuVo b2 = (RealSkuVo)a.clone();
		b2.setRealEan("asdasda2");
		b2.setRealQty(1);
		RealSkuVo b3 = (RealSkuVo)a.clone();
		b3.setRealEan("asdasda3");
		b3.setRealQty(1);
		RealSkuVo b4 = (RealSkuVo)a.clone();
		b4.setRealEan("asdasda3");
		b4.setRealQty(1);
		list.add(b1);
		list.add(b2);
		list.add(b3);
		list.add(b4);


		Map<String, LongSummaryStatistics> collect = list.stream().collect(Collectors.groupingBy(RealSkuVo::getRealEan,Collectors.summarizingLong(RealSkuVo::getRealQty)));


		Map<String, Long> collect1 = list.stream().collect(Collectors.groupingBy(RealSkuVo::getRealEan, Collectors.counting()));


		System.out.println(collect);
	}


}