How to make an array of arrays in Java

Like this:

String[][] arrays = { array1, array2, array3, array4, array5 };

or

String[][] arrays = new String[][] { array1, array2, array3, array4, array5 };

(The latter syntax can be used in assignments other than at the point of the variable declaration, whereas the shorter syntax only works with declarations.)


try

String[][] arrays = new String[5][];

While there are two excellent answers telling you how to do it, I feel that another answer is missing: In most cases you shouldn't do it at all.

Arrays are cumbersome, in most cases you are better off using the Collection API.

With Collections, you can add and remove elements and there are specialized Collections for different functionality (index-based lookup, sorting, uniqueness, FIFO-access, concurrency etc.).

While it's of course good and important to know about Arrays and their usage, in most cases using Collections makes APIs a lot more manageable (which is why new libraries like Google Guava hardly use Arrays at all).

So, for your scenario, I'd prefer a List of Lists, and I'd create it using Guava:

List<List<String>> listOfLists = Lists.newArrayList();
listOfLists.add(Lists.newArrayList("abc","def","ghi"));
listOfLists.add(Lists.newArrayList("jkl","mno","pqr"));

Tags:

Java

Arrays