java - Arrays.asList() doubt? -

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people aslist method convert array list , not copying, every change in 'alist' reflect 'a'. add new values in 'alist' illegal, since array have fixed size.

but, aslist() method returns arraylist<t>. how compiler differentiates line 3 5. line 3 gives me exception (unsupportedoperationexception).

        string[] = {"a","b","c","d"};//1         list<string> alist =  arrays.aslist(a);//2         alist.add("e");//3         list<string> b = new arraylist<string>();//4         b.add("a");//5

this list implementation receive arrays.aslist special view on array - can't change it's size.

the return type of arrays.aslist() java.util.arrays.arraylist confused java.util.arraylist. arrays.arraylist shows array as list.


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