Java8去重

package com.cdyfsz.autoaudit.rule.tool.test;

import com.cdyfsz.autoaudit.rule.tool.dto.ExcelAuditConclusionDto;
import com.cdyfsz.autoaudit.rule.tool.utils.CollectionUtils;

import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.util.function.Function;
import java.util.function.Predicate;
import java.util.stream.Collectors;
import static java.util.stream.Collectors.collectingAndThen;
import static java.util.stream.Collectors.toCollection;

public class testMain01 {
    public static void main(String[] args) {
        List<ExcelAuditConclusionDto> auditConclusionCodeList = new ArrayList<>();
        ExcelAuditConclusionDto excelAuditConclusionDto1 = new  ExcelAuditConclusionDto();
        excelAuditConclusionDto1.setAuditConclusionCode("01");
        excelAuditConclusionDto1.setAuditConclusion("结论1");
        excelAuditConclusionDto1.setAuditConclusionParentCode("001");
        ExcelAuditConclusionDto excelAuditConclusionDto2 = new  ExcelAuditConclusionDto();
        excelAuditConclusionDto2.setAuditConclusionCode("01");
        excelAuditConclusionDto2.setAuditConclusion("结论1");
        excelAuditConclusionDto2.setAuditConclusionParentCode("001");
        ExcelAuditConclusionDto excelAuditConclusionDto3 = new  ExcelAuditConclusionDto();
        excelAuditConclusionDto3.setAuditConclusionCode("02");
        excelAuditConclusionDto3.setAuditConclusion("结论2");
        excelAuditConclusionDto3.setAuditConclusionParentCode("002");

        auditConclusionCodeList.add(excelAuditConclusionDto1);
        auditConclusionCodeList.add(excelAuditConclusionDto2);
        auditConclusionCodeList.add(excelAuditConclusionDto3);




        if (CollectionUtils.isNotEmpty(auditConclusionCodeList)) {

            // 去重
            auditConclusionCodeList = auditConclusionCodeList.stream().collect(collectingAndThen(
                    toCollection(() -> new TreeSet<>(Comparator.comparing(ExcelAuditConclusionDto::getAuditConclusionCode))), ArrayList::new)
            );

            auditConclusionCodeList = auditConclusionCodeList.stream().collect(collectingAndThen(
                    toCollection(()-> new TreeSet<>(Comparator.comparing(ExcelAuditConclusionDto::getAuditConclusionCode))),ArrayList::new)
            );
            // 去重
            auditConclusionCodeList =  auditConclusionCodeList.stream().filter(distinctByKey(ExcelAuditConclusionDto::getAuditConclusionCode)).collect(Collectors.toList());


        }


        for (ExcelAuditConclusionDto rd :auditConclusionCodeList){
            System.out.println(rd.getAuditConclusionCode()+"====="+rd.getAuditConclusion());
        }


    }


    private static <T> Predicate<T> distinctByKey(Function<? super T, ?> keyExtractor) {
        Set<Object> seen = ConcurrentHashMap.newKeySet();
        return t -> seen.add(keyExtractor.apply(t));
    }
}