Java中大于二维数组的二维网格

Question

I'm writing a program that takes coordinates as input, and conceptualizes the coordinates in a grid, for which I'm using a 2D array. The problem is that some of the coordinates are larger than a billion, and I believe that the max size of a 2D array is somewhere around 800 million. I know that I can increase the memory allocated to the JVM to increase the max size; but is there a way to do this without going past the default max size, or another x by y grid system that doesn't have a max size? Thanks

Answer 1

Am I understanding you right? You would do something like this for (1,3)?

[0][0][1][0]
[0][0][0][0]
[0][0][0][0]
[0][0][0][0]

If your code requires an array of that size to store the coordinates, reconsider how your program works. One other way of storing coordinates with with an ArrayList or something where each entry would be a different occupied location in your array. That way you're only using memory for spots that are occupied and not ones that aren't. Because if you do it the way you plan, you'll be using 32 bits for EVERY coordinate on the grid when you KNOW most of them will be 0.