With this tutorial we shall show you how to use FileWriter and BufferedReader classes in odrer to append content to a file using Java. The idea is very simple.You have an already created File that has some content in it and you want to write new content at the end of the existing one.
In order to do that we are going to use the special FileWriter constructor: FileWriter(String fileName, boolean append). So if the second argument is true the file will be opened and the new content that we are going to write into it will be append at the end of the existing one. Note that if you just use the FileWriter(String fileName) constructor the file will be opened and when you try to write new content to the file the old one will be erased.
We have a txt file which already has a sentence written into it:
words.txt:
JavaCodeGeeks is the best!So, let’s take a look at the code:
package com.javacodegeeks.java.core;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
public class AppendFileJavaExample {
private static String filepath="C:\\Users\\nikos7\\Desktop\\words.txt";
public static void main(String[] args) {
try {
String newData = " Java is super cool!";
FileWriter fileWritter = new FileWriter(filepath, true);
BufferedWriter bwr = new BufferedWriter(fileWritter);
bwr.write(newData);
bwr.close();
System.out.println("The new content has been successfully appended to the File");
} catch (IOException e) {
e.printStackTrace();
}
}
}Output:
The new content has been successfully appended to the FileAnd the content of the file:
words.txt:
JavaCodeGeeks is the best! Java is super cool!
This was an example on how to append content to a file in Java.
