1，参数为null
当 Arrays.asList(null)//会报错：java.lang.NullPointerException
2，asList操作基本数据类型的数组，直接输出返回值为地址
int[] array02 = new int[]{1,2,3,4,5,6};
//Object list02 = Arrays.asList(array02);//返回值不是List<Integer>
System.out.println(Arrays.asList(array02));//输出值为地址
3，asList操作String类型的数组，返回的List大小固定，不能使用remove/add方法
String[] array = new String[]{"1","2","3","4","5","6"};
System.out.println(Arrays.asList(array));
//sList.add("1");//报错：java.lang.UnsupportedOperationException
//sList.remove("1");//报错：java.lang.UnsupportedOperationException
//原因：返回的ArrayList并不是ArrayList类，而是Arrays的内部类
Arrays.asList(array)调用如下方法：
/**
* Returns a fixed-size list backed by the specified array. (Changes to
* the returned list "write through" to the array.) This method acts
* as bridge between array-based and collection-based APIs, in
* combination with {@link Collection#toArray}. The returned list is
* serializable and implements {@link RandomAccess}.
*
* <p>This method also provides a convenient way to create a fixed-size
* list initialized to contain several elements:
* <pre>
* List<String> stooges = Arrays.asList("Larry", "Moe", "Curly");
* </pre>
*
* @param <T> the class of the objects in the array
* @param a the array by which the list will be backed
* @return a list view of the specified array
*/
@SafeVarargs
@SuppressWarnings("varargs")
public static <T> List<T> asList(T... a) {
return new ArrayList<>(a);
}
