java - Multi-Dimensional ArrayList initialized with values -

i'm new coding. teacher introduced arrays , arraylists. have multi-dimensional array this:

private string[][] pods = {{"pod1", ""}, {"pod2", ""}, {"pod3", ""}, {"pod4", ""}}; 

i'd switch arraylist, need edit information in there.

how this, multi-dimensional arraylist? i'd initialize above information.

i've tried this:

private arraylist<arraylist<string>> pods = new arraylist(); 

whenever put stuff between parenthesis, invalid operator error.

by way, in case wondering - not class assignment. i'm trying on own.

thanks.

firstly, approach half-correct.

you can have arraylist of arraylists double-dimensional array.

however...

you're initializing list raw type. java 7, can change assignment diamond-type inference:

list<list<string>> pods = new arraylist<>(); 

in earlier versions:

list<list<string>> pods = new arraylist<list<string>>(); 

you need populate lists.

for that, you'll need iteration.

here's complete java 7 example (using list "code interface" guideline suggests).

string[][] info = {{"pod1", ""}, {"pod2", ""}, {"pod3", ""}, {"pod4", ""}}; list<list<string>> pods = new arraylist<>(); (string[] level1: info) {     list<string> list = arrays.aslist(level1);     // use instead if intend modify inner lists     // list<string> list = new arraylist<>(arrays.aslist(level1));     pods.add(list); } system.out.println(pods); 

output

[[pod1, ], [pod2, ], [pod3, ], [pod4, ]] 

and now, java 8 mojo:

string[][] info = {{"pod1", ""}, {"pod2", ""}, {"pod3", ""}, {"pod4", ""}}; list<list<string>> pods =      arrays.stream(info)         .map((a) -> arrays.aslist(a))         // use instead if intend modify inner lists         // .map((a) -> arrays.stream(a).collect(collectors.tolist()))         .collect(collectors.tolist()); system.out.println(pods); 

(same) output

[[pod1, ], [pod2, ], [pod3, ], [pod4, ]]