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package com.zhifeng.sale;import com.zhifeng.sale.business.dto.SaleSettlementDetailDTO;import org.junit.Test;import java.math.BigDecimal;import java.util.ArrayList;import java.util.List;import java.util.Map;import java.util.stream.Collectors;public class StockZoneTest {    @Test    public void zoneTest(){        List
   
     settlementDetailDTOS = new ArrayList<>();        SaleSettlementDetailDTO s1 = new SaleSettlementDetailDTO();        s1.setStockZoneId("1");        s1.setSettlementFeeType("01");        s1.setSettlementPrice(new BigDecimal(100));        SaleSettlementDetailDTO s2 = new SaleSettlementDetailDTO();        s2.setStockZoneId("1");        s2.setSettlementFeeType("02");        s2.setSettlementPrice(new BigDecimal(100));        SaleSettlementDetailDTO s3 = new SaleSettlementDetailDTO();        s3.setStockZoneId("2");        s3.setSettlementFeeType("01");        s3.setSettlementPrice(new BigDecimal(200));        SaleSettlementDetailDTO s4 = new SaleSettlementDetailDTO();        s4.setStockZoneId("2");        s4.setSettlementFeeType("02");        s4.setSettlementPrice(new BigDecimal(200));        SaleSettlementDetailDTO s5 = new SaleSettlementDetailDTO();        s5.setStockZoneId("2");        s5.setSettlementFeeType("02");        s5.setSettlementPrice(new BigDecimal(500));        settlementDetailDTOS.add(s1);        settlementDetailDTOS.add(s2);        settlementDetailDTOS.add(s3);        settlementDetailDTOS.add(s4);        settlementDetailDTOS.add(s5);        Map
    
     > collect1 = settlementDetailDTOS.stream()                .filter(item -> item.getSettlementFeeType().equals("02"))                .collect(Collectors.groupingBy(SaleSettlementDetailDTO::getStockZoneId));        Map
     
      >> collect = settlementDetailDTOS.stream()                .filter(item -> item.getSettlementFeeType().equals("02"))                .collect(Collectors.groupingBy(SaleSettlementDetailDTO::getSettlementFeeType                        , Collectors.groupingBy(SaleSettlementDetailDTO::getStockZoneId)));        System.out.println(collect1);    }}