java.util.Arrays$ArrayList cannot be cast to java.util.ArrayList

完整报错：

HTTP Status 500 – Internal Server Error

---

Type Exception Report

Message Request processing failed; nested exception is java.lang.ClassCastException: java.util.Arrays$ArrayList cannot be cast to java.util.ArrayList

Description The server encountered an unexpected condition that prevented it from fulfilling the request.

Exception

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.ClassCastException: java.util.Arrays$ArrayList cannot be cast to java.util.ArrayList 
  
报错代码：
 
  
        String[] temp = s.split(",");

        //将结果作为ArrayList返回
        return （ArrayList）Arrays.asList(temp);
 
  
更正后写法：
 
  
 
 
  
   private ArrayList strToArrayList(String s){
        String[] temp = s.split(",");

        //将结果作为ArrayList返回
        List result = Arrays.asList(temp);
        ArrayList arrayList= new ArrayList<>(result);

        return arrayList;

    }
 
  
 错误原因：java.util.Arrays.ArrayList下有一个ArrayList子类，所以会出现这个错误，不能直接强转类型。
 
  
asList方法返回的是一个List，所以可以通过两步来将它转换成java.util.ArrayList的类型。