Arrays.asList使用注意

当传入的是基本类型时，会把传过来的数组作为list的第一个元素：

[java] view
plain copy

public class ArraysasList {  

  

    public static void main(String[] args) {  

        int[] a = {1,2,3,4,8,10,22,12,214,23};  

        String[] b = {"a","b","c"};  

        Integer[] c = {1,2,3,4,8,10,22,12,214,23};  

        System.out.println(a);  

        System.out.println(Arrays.asList(b));  

        System.out.println(Arrays.asList(c));  

    }  

  

}  

输出结果：

[I@179935d

[a, b, c]

[1, 2, 3, 4, 8, 10, 22, 12, 214, 23]

Arrays第二个问题，在添加或者删除的时候会报错：

[java] view
plain copy

public class ArraysasList {  

  

    public static void main(String[] args) {  

        int[] a = {1,2,3,4,8,10,22,12,214,23};  

        String[] b = {"a","b","c"};  

        Integer[] c = {1,2,3,4,8,10,22,12,214,23};  

        System.out.println(a);  

        System.out.println(Arrays.asList(b));  

        System.out.println(Arrays.asList(c));  

          

        List<String> bList = Arrays.asList(b);  

        bList.add("d");  

        System.out.println(bList);  

    }  

}  

Exception in thread "main" java.lang.UnsupportedOperationException
    at java.util.AbstractList.add(AbstractList.java:148)
    at java.util.AbstractList.add(AbstractList.java:108)
    at ArraysasList.main(ArraysasList.java:16)

源码中写到：

public   void   add( int   index, E element) {

07	throw   new   UnsupportedOperationException();

08

}

09

10	public   E remove( int   index) {

11	throw   new   UnsupportedOperationException();

12

}