package ee;

import java.util.HashMap;
import java.util.Iterator;

public class Demo {
    public static void main(String[] args) {
        HashMap<Integer, Integer> count = new HashMap<Integer, Integer>();
        count.put(1,11);
        count.put(2,22);
        count.put(3,33);
        //错误的 会抛出异常 ----ConcurrentModificationException
      /* for (Integer i : count.keySet()) {
            if(i == 2){
                count.remove(i);
            }
            System.out.println(i);
        }*/
        //正确的    it.remove();  // 这个可以实现 遍历的过程中删除某个元素
       Iterator<Integer> it = count.keySet().iterator();
        while(it.hasNext()) {
            Integer key = it.next();
            if(key == 2){
                it.remove();  // 这个可以实现 遍历的过程中删除某个元素
            }
            if(key == 3){
                count.put(key, 44);
            }
        }

        for (Integer value : count.values()) {
            System.out.println(value);
        }


    }

}