ArrayList快速失败机制源码及特殊失效场景分析

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简单的一个ArrayList案例

    public static void main(String[] args) {
   
        List<String> list = new ArrayList<>();
        list.add("1");
        list.add("2");
        list.add("3");
        for (String s : list){
   
            if ("1".equals(s)){
   
                list.remove(s);
            }
        }
    }

• 代码会正常执行吗？
  • 不会，那会导致什么？
  • 数组越界？

直接执行一下：

Connected to the target VM, address: '127.0.0.1:64296', transport: 'socket'
Exception in thread "main" java.util.ConcurrentModificationException
	at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:909)
	at java.util.ArrayList$Itr.next(ArrayList.java:859)
	at com.demo.demo.DemoApplicationTests.main(DemoApplicationTests.java:369)

介绍一下这个异常：

ConcurrentModificationException 并发修改异常

* This exception may be thrown by methods that have detected concurrent
 * modification of an object when such modification is not permissible.
 * <p>
 * For example, it is not generally permissible for one thread to modify a Collection
 * while another thread is iterating over it.  In general, the results of the
 * iteration are undefined under these circumstances.  Some Iterator
 * implementations (including those of all the general purpose collection implementations
 * provided by the JRE) may choose to throw this exception if this behavior is
 *