Iterator迭代的过程中使用list.remove

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在Iterator迭代的时候,

不能用list.remove(index)直接删除，将产生异常

可以用iterator.remove();

代码:

import java.util.ArrayList;import java.util.Arrays;import java.util.Iterator;import java.util.List;public class MyIterator {List<String> list = new ArrayList<String>(5);public void add() {list.addAll(Arrays.asList("1", "2", "3", "4", "5"));}public static void main(String args[]) {MyIterator myIt = new MyIterator();myIt.add();Iterator<String> iter = myIt.list.iterator();int i = 0;while (iter.hasNext()) {String s = (String) iter.next();System.out.println("" + s);if (s.equals("2")) {iter.remove();}//这一行将导致异常 java.util.ConcurrentModificationExceptionif (s.equals("3")) {myIt.list.remove(i);}i++;}myIt.list.remove(2);System.out.println(myIt.list);}}

异常:

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Exception in thread "main" java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:782)
at java.util.ArrayList$Itr.next(ArrayList.java:754)
at MyIterator.main(MyIterator.java:22)