Get Biggest Three Rhombus Sums in a Grid LeetCode solution in Java

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class Solution {
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  public int[] getBiggestThree(int[][] grid) {
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    int end = Math.min(grid.length, grid[0].length);
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    int maxThree[] = {0, 0, 0};
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    for (int length = 0; length < end; length++) {
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      searchBigThree(grid, maxThree, length);
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    }
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    Arrays.sort(maxThree);
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    // If there are less than three distinct values, return all of them.
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    if (maxThree[0] == 0) {
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      if (maxThree[1] == 0) {
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        return new int[] {maxThree[2]};
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      }
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      return new int[] {maxThree[2], maxThree[1]};
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    }
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    // reverse array
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    maxThree[0] = maxThree[0] ^ maxThree[2];
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    maxThree[2] = maxThree[0] ^ maxThree[2];
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    maxThree[0] = maxThree[0] ^ maxThree[2];
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    return maxThree;
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  }
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  void searchBigThree(int[][] grid, int[] maxThree, int length) {
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    int end = grid.length - (length == 0 ? 0 : 2 * length);
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    int end1 = grid[0].length - (length);
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    for (int start = 0; start < end; start++) {
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      for (int start1 = length; start1 < end1; start1++) {
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        if (start + start1 >= length) {
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          addToMaxThree(maxThree, getSum(grid, start, start1, length));
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        }
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      }
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    }
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  }
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  /*
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  get sum of edges of rhombus abcd
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          a
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         / \
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        d b
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         \ /
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          c
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  */
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  int getSum(int[][] grid, int i, int j, int length) {
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    if (length == 0) {
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      return grid[i][j];
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    }
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    int sum = 0;
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    // edge ab
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    for (int it = 0; it <= length; it++) {
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      sum = sum + grid[i + it][j + it];
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    }
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    // edge ad
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    for (int it = 1; it <= length; it++) {
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      sum = sum + grid[i + it][j - it];
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    }
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    // edge dc
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    for (int it = 1; it <= length; it++) {
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      sum = sum + grid[i + length + it][j - length + it];
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    }
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    // edge bc
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    for (int it = 1; it < length; it++) {
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      sum = sum + grid[i + length + it][j + length - it];
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    }
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    return sum;
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  }
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  void addToMaxThree(int[] maxThree, int num) {
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    // Do not add duplicate entry
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    if (maxThree[0] == num || maxThree[1] == num || maxThree[2] == num) {
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      return;
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    }
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    Arrays.sort(maxThree);
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    if (maxThree[0] < num) {
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      maxThree[0] = num;
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    }
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  }
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}