统计每个单词出现的次数

package cn.lbd.Collection;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;

/**统计单词出现的次数
 * this is a cat and this is a mice and where is the food?
 * 思路
 * 1.分割字符串
 * 2.分拣存储
 * 3.查看单词出现的次数
 * Created by linbingdong on 16/3/19.
 */
public class MapDemo01 {
    public static void main(String[] args){
        //分割字符串
        String[] arr = "this is a cat and this is a mice and where is the food?".split(" ");
        //分拣存储
        Map<String,Integer> map = new HashMap<String,Integer>();
        for (String key : arr){
            //System.out.println(key);
            if(!map.containsKey(key)){ //查看是否存在单词,不存在,加入
                map.put(key,1);
            }else{ //存在,value+1
                map.put(key,map.get(key)+1);
            }
        }
            //3.查看单词出现的次数
        Set<String> keySet = map.keySet();//将map中的key放入集合中
        Iterator<String> it = keySet.iterator();//调用迭代器遍历
        while (it.hasNext()){
            String key = it.next();
            Integer value = map.get(key);
            System.out.println(key+"--->"+value);
        }
    }
}