* 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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