Write to text file without overwriting in Java

Question

I am trying to write a method that makes a  log txt file  if one does not already exist and then writes to the file  The problem that I am encountering is every time I call the method  it overwrites the existing log  How do I change the method so that instead of overwriting the data it just updates the file   My Write File Method       File log   new File  log txt       try      if log exists    false               System out println  We had to make a new file                 log createNewFile              PrintWriter out   new PrintWriter log       out append              timeStamp toString                   n        out close         catch IOException e           System out println  COULD NOT LOG

User · Answer

try this one    x000D   x000D  public void writeFile String arg1 String arg2    x000D    try   x000D     if   dir exists      x000D   x000D      if  dir mkdirs      x000D   x000D       Toast makeText getBaseContext     Directory created   x000D         Toast LENGTH SHORT  show    x000D        else   x000D       Toast makeText getBaseContext    x000D          Error writng file     filename  Toast LENGTH LONG  x000D          show    x000D        x000D       x000D   x000D     else   x000D   x000D      File file   new File dir  filename   x000D      if   file exists      x000D       file createNewFile    x000D        x000D       x000D      FileWriter fileWritter   new FileWriter file  true   x000D      BufferedWriter bufferWritter   new BufferedWriter fileWritter   x000D      bufferWritter write arg1     n    x000D      bufferWritter close    x000D   x000D                catch  Exception e    x000D     e printStackTrace    x000D     Toast makeText getBaseContext    x000D        Error writng file     e toString    Toast LENGTH LONG  x000D        show    x000D      x000D   x000D     x000D   x000D   x000D

User · Answer

You can change your PrintWriter and use method getAbsoluteFile    this function returns the absolute File object of the given abstract pathname   PrintWriter out   new PrintWriter new FileWriter log getAbsoluteFile    true

User · Answer

use a FileWriter instead   FileWriter File file  boolean append    the second argument in the constructor tells the FileWriter to append any given input to the file rather than overwriting it   here is some code for your example   File log   new File  log txt    try      if  log exists             System out println  We had to make a new file             log createNewFile               FileWriter fileWriter   new FileWriter log  true        BufferedWriter bufferedWriter   new BufferedWriter fileWriter       bufferedWriter write              timeStamp toString                   n        bufferedWriter close         System out println  Done      catch IOException e        System out println  COULD NOT LOG

User · Answer

Here is a simple example of how it works  best practice to put a try catch into it but for basic use this should do the trick  For this you have a string and file path and apply thus to the FileWriter and the BufferedWriter  This will write  Hello World  Data variable  and then make a new line  each time this is run it will add the Data variable to the next line   import java io BufferedWriter  import java io File  import java io FileWriter    String Data    Hello World   File file   new File  C  Users stuff txt    FileWriter fw   new FileWriter file true   BufferedWriter bw   new BufferedWriter fw   bw write Data   bw newLine    bw close

User · Answer

You can even use FileOutputStream to get what you need  This is how it can be done   File file   new File Environment getExternalStorageDirectory     abc txt    FileOutputStream fOut   new FileOutputStream file  true   OutputStreamWriter osw   new OutputStreamWriter fOut   osw write  whatever you need to write    osw flush    osw close

User · Answer

Just change PrintWriter out   new PrintWriter log   to  PrintWriter out   new PrintWriter new FileWriter log  true

User · Answer

For some reason  none of the other methods worked for me   So i tried this and worked  Hope it helps    JFileChooser c  new JFileChooser    c showOpenDialog c   File write file   c getSelectedFile    String Content    Writing into file n hi  n hello  n hola   try        RandomAccessFile raf   new RandomAccessFile write file   rw        long length   raf length        System out println length       raf setLength length   1        integer value  for spacing     raf seek raf length         raf writeBytes Content       raf close       catch  Exception e        System out println e

User · Answer

JFileChooser c  new JFileChooser    c showOpenDialog c   File write file   c getSelectedFile    String Content    put here the data to be wriiten   try           FileWriter fw   new FileWriter write file       BufferedWriter bw   new BufferedWriter fw       bw append Content       bw append  hiiiii        bw close        fw close          catch Exception e           System out println e

User · Answer

BufferedWriter login   new BufferedWriter new FileWriter  login txt       is an example if you want to create a file in one line

[java] Write to text file without overwriting in Java

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