Can anyone help me with lines 144-168 of the skeleton program for COMP1 2015?

I just can't seem to understand what's happening on each line. I'm a real noob when it comes to programming, so if you guys could keep the language a little simple(stupid, I know since I'm doing AS Computing :P). Thanks guys.

boolean checkRedumMoveIsLegal(String[][] board, int startRank, int startFile, int finishRank, int finishFile, char colourOfPiece) {
    boolean redumMoveIsLegal = false;
    if (colourOfPiece == 'W') {
      if (finishRank == startRank - 1) {
        if ((finishFile == startFile) && (board[finishRank][finishFile].equals("  "))) {
          redumMoveIsLegal = true;
        } else {
          if ((abs(finishFile - startFile) == 1) && (board[finishRank][finishFile].charAt(0) == 'B')) {
            redumMoveIsLegal = true;
          }
        }
      }
    } else {
      if (finishRank == startRank + 1) {
        if ((finishFile == startFile) && (board[finishRank][finishFile].equals("  "))) {
          redumMoveIsLegal = true;
        } else {
          if ((abs(finishFile - startFile) == 1) && (board[finishRank][finishFile].charAt(0) == 'W')) {
            redumMoveIsLegal = true;
          }
        }
      }
    }
    return redumMoveIsLegal;   
  }