【Sets】使用Google Guava工程中Sets工具包，实现集合的并集/交集/补集/差集

获取两个txt文档的内容~存储进集合中求集合的并集/交集/补集/差集

package com.sxd.readLines.aboutDB;import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.File;import java.io.FileReader;import java.io.FileWriter;import java.io.IOException;import java.util.HashSet;import java.util.Set;import com.google.common.collect.Sets;public class Test {        /**     *      * @throws IOException     */    @org.junit.Test    public void test1() throws IOException  {        Set<String> set1 = readFile4List(new File("D:/B/1.txt"));        Set<String> set2 = readFile4List(new File("D:/B/DB.txt"));                Set<String> result1 = Sets.union(set1, set2);//合集，并集        Set<String> result2 = Sets.intersection(set1, set2);//交集        Set<String> result3 = Sets.difference(set1, set2);//差集 1中有而2中没有的        Set<String> result4 = Sets.symmetricDifference(set1, set2);//相对差集 1中有2中没有  2中有1中没有的 取出来做结果                //可以分别把4种不同结果 写出文件                BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(new File("d:/B/result.txt")));        bufferedWriter.write("共有:"+result1.size()+"条\r\n");        for (String string : result1) {            bufferedWriter.write(string+"\r\n");        }        bufferedWriter.close();                    }        public Set<String> readFile4List(File file) throws IOException{        BufferedReader bufferedReader = new BufferedReader(new FileReader(file));        Set<String> set = new HashSet<String>();        String str = null;        while((str =bufferedReader.readLine()) != null){            if(str.length() > 6){                set.add(str.substring(3));            }else{                set.add(str);            }                    }        return set;    }    }