String replace in a File

This is the code to replace the existing String with the given String in a given file present in the given directory.

Code:

public void replaceStringInFile(File dir, String fileName, String match, String replacingString){
try {
File file = new File(fileName);
if(file.isDirectory()||!file.exists()){
//the fileName specified is not a file hence returning.
return;
}
file = new File(dir, fileName);
RandomAccessFile randomAccessFile = new RandomAccessFile(file, "rw");
long fpointer = randomAccessFile.getFilePointer();
String lineData = "";
while((lineData =randomAccessFile.readLine()) != null){
fpointer = randomAccessFile.getFilePointer() - lineData.length()-2;
if(lineData.indexOf(match) > 0){
System.out.println("Changing string in file "+file.getName());
randomAccessFile.seek(fpointer);
randomAccessFile.writeBytes(replacingString);
// if the replacingString has less number of characters than the matching string line then enter blank spaces.
if(replacingString.length() < style="color: rgb(153, 0, 0);">int difference = (lineData.length() - replacingString.length())+1;
for(int i=0; i < style="color: rgb(51, 51, 255);">" ");
}
}
}
}
} catch (FileNotFoundException ex) {
ex.printStackTrace();
} catch (IOException ex) {
ex.printStackTrace();
} catch (Exception ex){
ex.printStackTrace();
}
}