Store a 2D array into an array?

Question

So I have this method here. This is creating a 2D array.

public static int[][] createCacheArray(int cacheSize, int blockSize, int[] memory, int i) {

    //Create multi-dimension array for cache.

    int [][] cache = new int [cacheSize/blockSize][blockSize];

    for (int column = 0; column < blockSize; column++) {
      for (int row = 0; row < cache.length; row++) {
           cache[row][column] = memory[i];
           i++;
      } 
    }

    return cache;

}

I would like to store the created Cache 2D array into a 1D array because I will be making multiple 2D cache arrays using this same method and I would like to organize them.

Basically I want to go to array [number] where a Cache 2D array is located and then read the contents of that cache 2D array. If there is another method I would gladly appreciate it.

The other way of doing it is this:

 cache = createCacheArray(cacheSize, blockSize, memory, (cacheSize * 0)); cache1 = createCacheArray(cacheSize, blockSize, memory, (cacheSize * 1)); cache2 = createCacheArray(cacheSize, blockSize, memory, (cacheSize * 2)); cache3 = createCacheArray(cacheSize, blockSize, memory, (cacheSize * 3)); 

Here, cache is 2D array, cache1 is a 2D array, cache 2 is a 2D array and so on, but this is inconvenient. The reason why im asking is because these are fixed 64x16 2D arrays. If an array gets filled, then I have to make another 2D array with the same size. Instead of making multiple variables, I was thinking it was possible to somehow store these onto an array. Like the 2D arrays are books and the 1D array is the shelf.

==================

The 2D arrays have numbers inside them.

After doing AndersonVieira's suggestion, all of my 2D arrays are stored into the ArrayList. This is perfect.

All I want to do now is search for a specific number in all of those 2D arrays inside the ArrayList. But I don't know what code to write to do this. I'm still a beginner in Java.

Answer 1

You could create a List<int[][]> and store your caches in there:

List<int[][]> caches = new ArrayList<>();
for (int i = 0; i < numCaches; i++) {
    caches.add(createCacheArray(cacheSize, blockSize, memory, (cacheSize * i)));
}

Then, you could access the caches by doing:

int[][] cache = caches.get(j);

Where j is the index of the desired element in the caches list.

Or, if you need to do something to each stored cache, you could iterate on the list:

for (int[][] cache : caches) {
    doSomething(cache);
}

This would probably be easier to work with than using a 3D array.

Edit:

To check if a 2-dimensional array contains an element, you need to loop through all the positions comparing the position value to the desired value:

static boolean contains(int element, int[][] cache) {
    for (int i = 0; i < cache.length; i++) {
        for (j = 0; j < cache[i].length; j++) {
            if (cache[i][j] == element) {
                return true;
            }
        }
    }
    return false;
}

Then you could create a method that returns the first cache that contains the specified element, or null otherwise:

static int[][] cacheContaining(int element, List<int[][]> caches) {
    for (int[][] cache : caches) {
        if (contains(element, cache)) {
            return cache;
        }
    }
    return null;
}

Answer 2

You could use a 3d array like,

int[][][] cache = {
    createCacheArray(cacheSize, blockSize, memory, (cacheSize * 0)),
    createCacheArray(cacheSize, blockSize, memory, (cacheSize * 1)),
    createCacheArray(cacheSize, blockSize, memory, (cacheSize * 2)),
    createCacheArray(cacheSize, blockSize, memory, (cacheSize * 3))
};
System.out.println(Arrays.deepToString(cache);