* 从迭代器指向的 collection 中移除当前迭代元素

* 来达到删除访问中的元素的目的。

* */

public static void main(String[] args) {

map.put(1,"one");

map.put(2,"two");

map.put(3,"three");

map.put(4,"four");

map.put(5,"five");

map.put(6,"six");

map.put(7,"seven");

map.put(8,"eight");

map.put(5,"five");

map.put(9,"nine");

map.put(10,"ten");

Iterator<Map.Entry<Integer, String>> it = map.entrySet().iterator();

while(it.hasNext()){

Map.Entry<Integer, String> entry=it.next();

int key=entry.getKey();

if(key%2==1){

System.out.println("delete this: "+key+" = "+key);

//map.put(key, "奇数"); //ConcurrentModificationException

//map.remove(key); //ConcurrentModificationException

it.remove(); //OK

}

}

//遍历当前的map；这种新的for循环无法修改map内容，因为不通过迭代器。

System.out.println("-------nt最终的map的元素遍历：");

for(Map.Entry<Integer, String> entry:map.entrySet()){

int k=entry.getKey();

String v=entry.getValue();

System.out.println(k+" = "+v);

}

}

}

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