170、从类似如下的文本文件中读取出所有的姓名，并打印出重复的姓名和重复的次数
170、从类似如下的文本文件中读取出所有的姓名，并打印出重复的姓名和重复的次数，并按重复次数排序：1,张三,282,李四,353,张三,284,王五,355,张三,286,李四,357,赵六,288,田七,35
程序代码如下（答题要博得用人单位的喜欢，包名用该公司，面试前就提前查好该公司的网址，如果查不到，现场问也是可以的。还要加上实现思路的注释）：package com.huawei.interview;import java.io.BufferedReader;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.util.Comparator;import java.util.HashMap;import java.util.Iterator;import java.util.Map;import java.util.TreeSet;public class GetNameTest {
/*** @param args*/public static void main(String[] args) {// TODO Auto-generated method stub//InputStream ips = GetNameTest.class.getResourceAsStream("/com/huawei/interview/info.txt");//用上一行注释的代码和下一行的代码都可以，因为info.txt与GetNameTest类在同一包下面，所以，可以用下面的相对路径形式Map results = new HashMap();InputStream ips = GetNameTest.class.getResourceAsStream("info.txt");BufferedReader in = new BufferedReader(new InputStreamReader(ips));String line = null;try {while((line=in.readLine())!=null){dealLine(line,results);}sortResults(results);} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}static class User{publicString name;public Integer value;public User(String name,Integer value){this.name = name;this.value = value;}
@Overridepublic boolean equals(Object obj) {// TODO Auto-generated method stub//下面的代码没有执行，说明往treeset中增加数据时，不会使用到equals方法。boolean result = super.equals(obj);System.out.println(result);return result;}}private static void sortResults(Map results) {// TODO Auto-generated method stubTreeSet sortedResults = new TreeSet(new Comparator(){public int compare(Object o1, Object o2) {// TODO Auto-generated method stubUser user1 = (User)o1;User user2 = (User)o2;/*如果compareTo返回结果0，则认为两个对象相等，新的对象不会增加到集合中去* 所以，不能直接用下面的代码，否则，那些个数相同的其他姓名就打印不出来。* *///return user1.value-user2.value;//return user1.value<user2.value?-1:user1.value==user2.value?0:1;if(user1.value<user2.value){return -1;}else if(user1.value>user2.value){return 1;}else{return user1.name.compareTo(user2.name);}}});Iterator iterator = results.keySet().iterator();while(iterator.hasNext()){String name = (String)iterator.next();Integer value = (Integer)results.get(name);if(value > 1){sortedResults.add(new User(name,value));}}printResults(sortedResults);}private static void printResults(TreeSet sortedResults){Iterator iterator= sortedResults.iterator();while(iterator.hasNext()){User user = (User)iterator.next();System.out.println(user.name + ":" + user.value);}}public static void dealLine(String line,Map map){if(!"".equals(line.trim())){String [] results = line.split(",");if(results.length == 3){String name = results;Integer value = (Integer)map.get(name);if(value == null) value = 0;map.put(name,value + 1);}}}}
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