Thread: Very simple file I/O question

So I'm practicing file I/O, but I know nothing about it in java.

I keep getting my file erased every time I call my function.

What happens is this:

I call the "createNewPlayer" function, and it creates the player and writes it to the player info to the file, no problem.
Then I call it again for the second player, and it immediately erases the player information, and then ends up putting in the new information, but it's missing the original info.

...here's the code.

public void play() throws Exception
        {
                boolean play;
 
                // ask user if he wants to play
                play = promptToPlay();
 
                java.io.File file = new java.io.File("Tic-Tac-Toe.txt");
 
                if(play)
                {
                        boolean new_player;
 
                        new_player = promptNew_Existing();
 
                        if(new_player)
                        {
                                [B]player1 = createNewPlayer(file);[/B]
                        }
                        else
                                player1 = retrievePlayer(file); //get user name and stuff
 
                        new_player = promptNew_Existing();
 
                        if(new_player)
                        {
                                [B]player2 = createNewPlayer(file);[/B]
                        }
                        else
                                player2 = retrievePlayer(file);
 
 
                        player1.inCellValue = 9;
                        player2.inCellValue = 1;
        }

And then my createPlayer function....

Note the line that I originally commented out. That's when I was getting the erased file, so I've tried fixing the problem. I'm presuming that creating a new file erases the original one.

As a result, I'm trying to pass a file through the function, and then open the file.

However, I don't even know how to open a file in java lol. The syntax is apparently wrong. Plus I don't even know if this will prevent the file from being erased.

public Player createNewPlayer(java.io.File file) throws Exception
        {
                Player player = new Player();
 
//              java.io.File file = new java.io.File("Tic-Tac-Toe.txt");
 
                java.io.PrintWriter output;
                output.open(file);
 
                // receive player info
                player.receiveName();
                player.receiveSymbol();
 
 
                // write player information to file
                output.println(player.name + " " + player.symbol + " " + player.numWins + " " + player.numLosses);
 
                output.close();
 
                return player;
        }

Thanks in advance.

What exactly do you mean by "use FileWriter instead"?

I changed

java.io.PrintWriter output;
         output.open(file);;

To

java.io.FileWriter output = new java.io.FileWriter(file, true);

I added the "true" because I looked up the constructors and apparently that appends to the end of the file? I presume that's what I want to do.

But this doesn't compile....so I'm doing something wrong.

Here it is

HTML Code:

output.println(player.name + " " + player.symbol + " " + player.numWins + " " + player.numLosses);
                      ^
  symbol:   method println(String)
  location: variable output of type FileWriter
1 error

Errr that formatting seems to be bad

HTML Code:

TicTacToe.java:154: error: cannot find symbol
                output.println(player.name + " " + player.symbol + " " + player.numWins + " " + player.numLosses);
                      ^
  symbol:   method println(String)
  location: variable output of type FileWriter
1 error

Note the difference in the ^ symbol

--- Update ---

OK....and....API? What's that?

Oh okay, I just did it.

You're supposed to use "write" not "println" ..... they're very sneaky!!

Haha, thanks a lot for the help man. Finally got it up and compiling.