arrays - How to add item to a list of arraylist that filled before in java -


i have booklist below

public static arraylist<list<string>> bookslist = new arraylist<list<string>>();

and filled shown below,

bookslist.add(arrays.aslist("coders @ work", null)); bookslist.add(arrays.aslist("code complete",null)); bookslist.add(arrays.aslist("the mythical man month",null)); bookslist.add(arrays.aslist("don't make me think",null)); bookslist.add(arrays.aslist("the pragmatic programmer",null));

i want add item list of specific row of arraylist

bookslist.get(0).add("buyed"); bookslist.get(0).add(0,"buyed");

but doesn't work. how add more items? or there better way handle situation?

you cannot add or remove elements of list created arrays.aslist().

its javadoc states indeed :

returns fixed-size list backed specified array.

to able add new elements after list created, wrap fixed size list in new arraylist.

for example :

bookslist.add(arrays.aslist("coders @ work", null));

could written :

bookslist.add(new arraylist<>(arrays.aslist("coders @ work", null)));

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