Finding valid neighbors in 2D array

Question

So, I have a 4x4 2D array (it will always be these dimensions). Starting with a location on the array, some row and column, I want to find all of its valid neighbors. So far, I

Answer 1

public class FindingNeighboursInMatrix {

public static void main(String[] args) {
    int array[][] = { { 1, 2, 3, 4 }, 
                      { 5, 6, 7, 8 }, 
                      { 9, 10, 11, 12 } };

    for (int i = 0; i < array.length; i++) {

        for (int j = 0; j < array[0].length; j++) {

            System.out.println("neightbours of " + array[i][j]);
            int neb[] = findneighbours(i, j, array);
            for (int k = 0; k < neb.length; k++) {
                if (neb[k] != -1) {
                    System.out.print(" " + neb[k] + ",");
                }
            }
            System.out.println();
        }

    }

}

public static int[] findneighbours(int i, int j, int matrix[][]) {
    int neb[] = new int[8];
    // top row
    neb[0] = getvalue(i - 1, j - 1, matrix);
    neb[1] = getvalue(i - 1, j, matrix);
    neb[2] = getvalue(i - 1, j + 1, matrix);

    // left element

    neb[3] = getvalue(i, j - 1, matrix);

    // right element

    neb[4] = getvalue(i, j + 1, matrix);

    // bottom row
    neb[5] = getvalue(i + 1, j - 1, matrix);
    neb[6] = getvalue(i + 1, j, matrix);
    neb[7] = getvalue(i + 1, j + 1, matrix);

    return neb;

}

public static int getvalue(int i, int j, int matrix[][]) {
    int rowSize = matrix.length;
    int colSize = matrix[0].length;

    if (i < 0 || j < 0 || i > rowSize - 1 || j > colSize - 1) {
        return -1;
    }
    return matrix[i][j];
}}