Learn Java by Example: Java Program to Calculate Standard Deviation

Java Program to Create File and Write to the File

In this example, we will learn to create files in Java and write some information to the file.


Example 1: Java Program to Create a File

// importing the File class
import java.io.File;

class Main{
  public static void main(String[] args){

    // create a file object for the current location
    File file = new File("JavaFile.java");

    try {

      // create a new file with name specified
      // by the file object
      boolean value = file.createNewFile();
      if (value) {
        System.out.println("New Java File is created.");
      else {
        System.out.println("The file already exists.");
    catch(Exception e) {

In the above example, we have created a file object named file. The file object is linked with the specified path.

// javaFile.java is equivalent to
// currentdirectory/JavaFile.java
File file = new File("JavaFile.java");

We then use the createNewFile() method of the File class to create new file to the specified path.

Note: If the file JavaFile.java is not already present, then only the new file is created. Otherwise the program returns The file already exists.

Example 2: Java Program to Write Content to the File

In Java, we can use the FileWriter class to write data to a file. In the previous example, we have created the file named JavaFile.java. Now let’s write a program to the file.

// importing the FileWriter class
import java.io.FileWriter;

class Main{
  public static void main(String args[]){

    // creates a multiline string using + operator
    // the string is a Java Program
    String program = "class JavaFile { " +
                       "public static void main(String[] args) { " +
                         "System.out.println("This is file");"+
     try {
       // Creates a Writer using FileWriter
       FileWriter output = new FileWriter("JavaFile.java");

       // Writes the program to file
       System.out.println("Data is written to the file.");

       // Closes the writer
     catch (Exception e) {

In the above example, we have used the FileWriter lass to write the string data to the file Javafile.java.

When you run the program, the file JavaFile.java will includes the data present in the string program.



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Disclaimer: The information and code presented within this recipe/tutorial is only for educational and coaching purposes for beginners and developers. Anyone can practice and apply the recipe/tutorial presented here, but the reader is taking full responsibility for his/her actions. The author (content curator) of this recipe (code / program) has made every effort to ensure the accuracy of the information was correct at time of publication. The author (content curator) does not assume and hereby disclaims any liability to any party for any loss, damage, or disruption caused by errors or omissions, whether such errors or omissions result from accident, negligence, or any other cause. The information presented here could also be found in public knowledge domains.