Fixing Movement Logic in Java

Question

I currently developing a Chess Game in java using the eclipse IDE,

I Have all the movement of the pieces down apart from the Pawn which is the hardest because the Pawn has to be able to make to different moves

The Pawn should be able to move twice at the start and then only one after that

Currently I have set the pawn to only move twice but I am stuck on getting the rest of the logic to work

I have been working with the idea of an if/else statement

I could use some help writing it

Here is the Code so far for the Pawn and I have included comment's for your use

Update to Problem it is only with the black pawn is not moving right I was able to set the white one the right way but not the black I dont know why it doesnt work

 //Pawn Movement
    private boolean isValidPawnMove(int sourceRow, int sourceColumn, int targetRow, int targetColumn) {

        boolean isValid = false;
        if( isTargetLocationFree() ){
            if( sourceColumn == targetColumn){
                if(  sourcePiece.getColor() == Piece.COLOR_WHITE ){

                    // White Pawn
                    if( sourceRow+1 == targetRow || sourceRow == 1 && targetRow == 3){//Pawns can move to at the start then only 1 after that 
                        isValid = true;
                    }else{
                        isValid = false;
                    }
                }
                else{

                    // Black Pawn
                    if( sourceRow-1 == targetRow || sourceRow == -1 && targetRow == -3){
                        isValid = true;
                    }else{
                        isValid =  false;
                    }
                }
            }else{

                //If you try to move left or right into a different Column 
                isValid = false;

            }

        //Take square occupied by an opponent’s piece, which is diagonally in front 
        }else if( isTargetLocationCaptureable() ){

            if( sourceColumn+1 == targetColumn || sourceColumn-1 == targetColumn){
                //One column to the right or left
                if(  sourcePiece.getColor() == Piece.COLOR_WHITE ){
                    //White Piece 
                    if( sourceRow+1 == targetRow ){
                        //Move one up
                        isValid = true;
                    }else{
                        //Not moving one up
                        isValid = false;
                    }
                }else{
                    //Black Piece
                    if( sourceRow-1 == targetRow ){
                        //Move one down
                        isValid = true;
                    }else{
                        //Not moving one down
                        isValid = false;
                    }
                }
            }else{
                //Not one column to the left or right
                isValid = false;
            }
        }
        return isValid;
    }

Thanks for any help you can provide

Answer 1

I think the easiest solution is to explicitly check the source and target rows as white pawns can only move two forward from the second rank, so your logic becomes (for white):

if( sourceRow+1 == targetRow || sourceRow == 2 && targetRow == 4) {

Obviously you will also need to check that (sourceColumn, 3) is also empty.