I've run into some problems trying to append to an existing text file.
It doesn't seem to append a line text. So far i've got this method:
public static void addLine(File f, String line) {
try {
FileWriter fw = new FileWriter(f.getName(), true);
BufferedWriter buffer = new BufferedWriter(fw);
PrintWriter pw = new PrintWriter(buffer);
pw.println(line);
pw.close();
} catch (IOException e) {
System.err.println("IOException: " + e.getMessage());
}
}
and in my main i've got the following:
public static void main(String[] args) {
File f = new File("adresOfFile");
if (f.exists() && !f.isDirectory()) {
System.out.println("File " + f.getName() + " exists!");
System.out.println("\n" + "Path: " + f.getAbsolutePath());
System.out.println("\n" + "Parent: " + f.getParent());
System.out.println("\n" + "--------------CONTENT OF FILE-------------");
addLine(f, "");
addLine(f, "The line to append");
try {
displayContent(f);
} catch (IOException e) {
System.out.println(e.getMessage());
}
} else {
System.out.println("File not found");
}
}
When I run the program it doesn't seem to give any errors. Running the program should print out the existing text (displayContent), which is done after appending (addLine). But when I run it, it only shows the existing text, without the appended line.
It doesn't show up in the text file either. I tried to put a System.out.println(); in the method, and it prints, so I know its running the method properly, just not appending.
EDIT AWNSER: replaced f.getName() with f, and added pw.flush before pw.close()
I think that your displayContent(File) function has bugs.
The above code does append to the file. Have a look at the file to see if anything is appended.
Also do you need to create PrintWriter object each time you append a line? If there are many continuous lines to be appended, try using a single PrintWriter/ BufferedWriter object by creating a static/final object.
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