initial boat placement for battleship game

boat_placement.java

/*
	Initialize all boat positions for a given player
*/
private boolean initBoatPositions(String message) {
	boatPositions = new String[(Player.boats).length][];
	String[] boatInfo = message.split(",");
	
	ArrayList<String> usedPositions = new ArrayList<String>();
	
	for(String boat : boatInfo) {
		int boatIndex;
		String[] explodedBoat = boat.split("\\s+");
		
		for(boatIndex=0; boatIndex < (Player.boats).length; boatIndex++)
			if(explodedBoat[0].equals(Player.boats[boatIndex]))
				break;
		
		if(boatIndex >=0) {
			if(!addBoat(boatIndex, explodedBoat, usedPositions)) {
				return false;
			}
		}
		else
			return false;
	}
	
	return true;
}


/*
	Add a boat position to the player's boat setup.
*/
private boolean addBoat(int boatIndex, String[] explodedBoat, ArrayList<String> usedPositions) {
	if(boatPositions[boatIndex] != null)
		return false;
		
	if(explodedBoat.length-1 != Player.boatLengths[boatIndex])
		return false;
				
	boatPositions[boatIndex] = new String[Player.boatLengths[boatIndex]];
		
	for(int i=1; i < explodedBoat.length; i++) {
		if(validPosition(explodedBoat[i]) && !usedPositions.contains(explodedBoat[i])) {
			boatPositions[boatIndex][i-1] = explodedBoat[i];
			usedPositions.add(explodedBoat[i]);
		}
		else
			return false;
	}
	
	String fPos = boatPositions[boatIndex][0];
	char i;
	int j, ncol, nrow;
	ncol = nrow = 0;			
	i = fPos.charAt(0);
	j = Integer.parseInt(fPos.substring(1,fPos.length()));
		
	for(String pos : boatPositions[boatIndex]) {
		if(pos.charAt(0) == i)
			nrow++;
		if(Integer.parseInt(pos.substring(1, pos.length())) == j)
			ncol++;	
	}
		
	if((ncol !=  Player.boatLengths[boatIndex]) && (nrow != Player.boatLengths[boatIndex]))
		return false;		
	
	return true;	
}

/*
	Validates that a given string position
	is a valid position on the game board
	(in range A1-J10)
*/
private boolean validPosition(String position) {
	try {
		if(1 < position.length() && position.length() < 4) {
			int m = position.charAt(0) - 64;
			int n = Integer.parseInt(position.substring(1, position.length()));
		
			if(m > 10 || n < 1)
				return false;
			if(1 < (m+n) && (m+n) < 21)
				return true;
		}
		return false;
	} catch(NumberFormatException nfe) {
		return false;
	}
}