guava常用集合交集，差集，并集，补集操作

 <!-- https://mvnrepository.com/artifact/com.google.guava/guava -->
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>21.0</version>
        </dependency>

　<!-- https://mvnrepository.com/artifact/com.google.guava/guava -android结尾兼容jdk1.7 -->
　　　　　<dependency>
   　　　　　　<groupId>com.google.guava</groupId>
    　　　　　　<artifactId>guava</artifactId>
   　　　　　　 <version>22.0-android</version>
　　　　　</dependency>

　　<!-- https://mvnrepository.com/artifact/net.sourceforge.javacsv/javacsv -->
　　　　　　<dependency>
　　　　　　　　<groupId>net.sourceforge.javacsv</groupId>
　　　　　　　　<artifactId>javacsv</artifactId>
　　　　　　　　<version>2.0</version>
　　　　　　</dependency>

引用guava jar文件
工具增强型：https://www.simonjia.top/656.html

import com.csvreader.CsvReader;
import com.google.common.collect.Sets;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.nio.charset.Charset;
import java.util.*;

import static com.google.common.collect.Sets.newHashSet;

/**
 * @Author: SimonHu
 * @Date: 2019/11/12 14:35
 * @Description:
 */
public class BillCompareUtil {
    private static final Logger log = LoggerFactory.getLogger(BillCompareUtil.class);
    
    public static void main(String[] args) {
        String csvFilePath02 = "C:\\Users\\admin\\Desktop\\app订单0905-02.csv";
        String csvFilePath01 = "C:\\Users\\admin\\Desktop\\app订单0905.csv";
        compare(csvFilePath01, csvFilePath02, 3);
    }
    
    /**
     * @param path1
     * @param path2
     * @param type  1交集2差集3并集
     * @return java.util.Map
     * @Description:对比文档 运行出错，请注意使用jdk1.8以上进行编译
     * @Author:SimonHu
     * @Date: 2019/11/12 14:44
     */
    public static Map compare(String path1, String path2, int type) {
        ArrayList<String[]> csvList01 = new ArrayList<String[]>();
        ArrayList<String[]> csvList02 = new ArrayList<String[]>();
        try {
            long start = System.currentTimeMillis();
            Set<Map<String, String>> set1 = newHashSet();
            Set<Map<String, String>> set2 = newHashSet();
            //解决中文编码
            CsvReader reader01 = new CsvReader(path1, ',', Charset.forName("GBK"));
            CsvReader reader02 = new CsvReader(path2, ',', Charset.forName("GBK"));
            //reader.readHeaders(); // 跳过表头   如果需要表头的话，不要写这句。
            //逐行读入除表头的数据
            while (reader01.readRecord()) {
                csvList01.add(reader01.getValues());
            }
            //逐行读入除表头的数据
            while (reader02.readRecord()) {
                csvList02.add(reader02.getValues());
            }
            reader01.close();
            reader02.close();
            for (int row = 0; row < csvList01.size(); row++) {
                Map<String, String> map01 = new HashMap();
                String cell0 = csvList01.get(row)[0];
                String cell1 = csvList01.get(row)[1];
                map01.put("订单号", cell0);
                if (cell1.indexOf(".") == -1) {
                    map01.put("金额", cell1);
                } else {
                    String cell2 = cell1.substring(0, cell1.indexOf("."));
                    map01.put("金额", cell2);
                }
                set1.add(map01);
            }
            for (int row = 0; row < csvList02.size(); row++) {
                Map<String, String> map02 = new HashMap();
                String cell0 = csvList02.get(row)[0];
                String cell1 = csvList02.get(row)[1];
                if (cell1.indexOf(".") == -1) {
                    map02.put("订单号", cell0);
                    map02.put("金额", cell1);
                } else {
                    String s01 = cell1.substring(0, cell1.indexOf("."));
                    map02.put("订单号", cell0);
                    map02.put("金额", s01);
                }
                set2.add(map02);
            }
            Map map = new HashMap();
            List<Map> resultList = new LinkedList<>();
            Sets.SetView result = null;
            if (type == 1) {
                result = Sets.intersection(set1, set2);
                System.out.println("交集  intersection:");
                //intersection交集:
            } else if (type == 2) {
                 result = Sets.difference(set1, set2);
                System.out.println("补集  difference:");
                //difference 补集:这里其实是set2相对于set1的补集
            } else if (type == 3) {
                result = Sets.union(set1, set2);
                System.out.println("并集 union:");
            }else if(type == 4){
                //差集
　　　　　　　　　　result = Sets.symmetricDifference(set1,set2)

　　　　　　　 }
            int i=0;
            for (Object u : result) {
                i++;
                Map paramMap = new HashMap();
                System.out.println(u.toString());
                paramMap.put("text","序号:"+i+"------"+u.toString());
                resultList.add(paramMap);
            }
            Map countMap = new HashMap();
            countMap.put("text","总计:"+i+" 条");
            resultList.add(0,countMap);
            map.put("list", resultList);
            long end = System.currentTimeMillis();
            System.out.println((end - start) + "==========ms");
            return map;
        } catch (IOException e) {
            log.error("文件对比失败------", e);
            return null;
        }
    }
}

csv源文件

app订单0905-02.csv

"201992307383892601","490000.00"
"201950907854593602","490000.00"

app订单0905.cdv

"201992307383892601","490001.00"
"201950907854593602","490000.00"

对比结果

交集 intersection:
{orderNo=201950907854593602, trxAmt=490000}
补集 difference:
{orderNo=201992307383892601, trxAmt=490001}
并集 union:
{orderNo=201992307383892601, trxAmt=490001}
{orderNo=201950907854593602, trxAmt=490000}
{orderNo=201992307383892601, trxAmt=490000}

差集 symmetricDifference:
{orderNo=201950907854593602, trxAmt=4901}
{orderNo=201992307383892601, trxAmt=4900}
{orderNo=201950907854593602, trxAmt=4902}

lib引用jar

guava-21.0.jar 
javacsv.jar