Write file with RandomAccessFile.

Question

I am trying to read one file and writting in same file be using Random access file .
File is properties file having Key = Value Pair . where values are empty
When i try to write in file File Pointer is at end of line .
Instead of writing to same line it is writing to new line and overwriting new line contents .
For eg.
this is content =..
So i want write after "=" sign How do i do this
RandomAccessFile raf = new RandomAccessFile("D:\\ycdfcpcaliterals2translate.properties", "rw");
          long filesize1 = raf.length();
          try {
               long fptr =0;
               String line = null;
               while ( (raf.length()-fptr) >0 ) {
                    line = raf.readLine();
                    fptr = raf.getFilePointer();
                    raf.seek(fptr);
                    if ( line != null){
                          raf.writeBytes("Written"); // Want to write Here at end of line
               raf.close();
          } catch (IOException ioErr) {
               System.err.println(ioErr);
          } Please suggest solution

Answer 1

First, the method RandomAccessFile.readLine() reads a full line including the new-line character. To position the file pointer just before the new line, you should seek one position backwards.
More to the point, writing to a RandomAccessFile is always done in "overwrite mode"; you cannot insert characters. Therefore, to achieve the effect of inserting characters, you need to re-write the whole file from the insertion point and onwards. It's probably easiest to write to a temporary file.