1、这个问题是谁提出来的啊，我不会打死你，只会打残你啊，理想很丰满，现实很残酷
2、解决代码如下建立一个hashMap,数值类型为String
3、遍历m1的值，然后赋值到al1找到values值相等的str1
4、输出等于strl值的key值
5、package javaChengShengZhiLu.JavaJichu;import java.util.ArrayList;import java.util.Co造婷用痃llection;import java.util.HashMap;import java.util.HashSet;import java.util.Iterator;import java.util.List;import java.util.Map;import java.util.Set;/*** 把Map集合中value值相同的Key取出来* @author 黄河涛涛h**/public class Map1 { public static void main(String[] args) { //建立一个hashMap,数值类型为String Map<String,String> m1 = new HashMap<String,String>(); m1.put("one","黄"); m1.put("two","河"); m1.put("three","涛"); m1.put("four","涛"); m1.put("five","h"); m1.put("six","牛"); m1.put("seven","B"); //建立一个数组用来存储m1的数值 List<String> al1 = new ArrayList<String>(); //遍历m1的值，然后赋值到al1 Collection values = m1.values(); for(Iterator iterator1 = values.iterator();iterator1.hasNext();){ al1.add((String) iterator1.next()); } //System.out.println(al1.size()); //找到values值相等的str1 String str1 = null; for(int i=0;i<al1.size()-1;i++){ for(int j=i+1;j<al1.size();j++){ if(al1.get(i)==al1.get(j)){ System.out.println(al1.get(i)); str1 = al1.get(i); } } } //输出等于strl值的key值 Collection col1 = m1.entrySet(); String str2 = null; for(Iterator ite2 = col1.iterator();ite2.hasNext();){ Object obj = ite2.next(); str2 = obj.toString(); if(str1.equals(str2.substring(str2.indexOf("=")+1,str2.length()))){ System.out.println(str2.substring(0,str2.lastIndexOf("="))); } } }}
6、代码运行结果
