写一个程序，用于分析一个字符串中各个单词出现的频率，并将单词和它出现的频率输出显示。（单词之间用空格隔开，如“Hello World My First Unit Test”）

public class Test {

public void index() {

String strWords = "Hello World My First Unit Test";

String[] words_Array = strWords.split(" ");

Map<String,Integer> words_Map=new HashMap<String, Integer>();

int arrLength = words_Array.length;

for(int i=0;i<arrLength;i++){

if(!words_Map.containsKey(words_Array[i])){

words_Map.put(words_Array[i], 1);

System.out.println(words_Array[i]);

System.out.println("出现");

System.out.println(words_Map.put(words_Array[i], 1));

System.out.println("次");

}else{

int currentNum = words_Map.get(words_Array[i])+1;

words_Map.remove(words_Array[i]);

words_Map.put(words_Array[i], currentNum);

System.out.println(words_Array[i]);

System.out.println("出现");

System.out.println(words_Map.put(words_Array[i], currentNum));

System.out.println("次");

}

}

}

}