Appending to a file in java

Question

I am working on a project. For the project I am using GUI and I want to write a number to a file. I have been successful, and I can write the number to the file that i want to. My problem that hopefully someone can give insite to is that everytime i write a number to a file the new number replaces the old one. How would i go about keeping the current info in the file. My code is:

  public static void writeCodeFile (String filename, int x, String userName) throws IOException{
        BufferedWriter outputWriter = null;
        outputWriter = new BufferedWriter(new FileWriter(filename));
        outputWriter.newLine();
        outputWriter.write(userName +":"+ Integer.toString(x));
        outputWriter.newLine();
        outputWriter.flush();  
        outputWriter.close();   



}

The FileWriter constructor has an overload that would be useful, one with a boolean parameter. — Hovercraft Full Of Eels, Dec 14 '12 at 01:07

score 3 · Accepted Answer · answered Dec 14 '12 at 01:07

3

Use append mode:

outputWriter = new BufferedWriter(new FileWriter(filename, true));

answered Dec 14 '12 at 01:07

Mordechai

15,437
2
41
82

@toby1618 This is straight-forward but dumb solution, especially if you call `writeCodeFile` in a loop. – Nikolay Kuznetsov Dec 14 '12 at 01:27

score 1 · Answer 2 · answered Dec 14 '12 at 01:07

1

When you create the FileWriter, add a second parameter "true" to go into append mode.

answered Dec 14 '12 at 01:07

DrC

7,528
1
22
37

Appending to a file in java

2 Answers2