Java File Handling: Creating and Writing to Files

Discover how to create and write to files in Java using the createNewFile() method from the File class. This method returns true if the file is successfully created and false if it already exists. Learn the essential steps for effective file handling, including best practices for managing file input and output in your Java applications to ensure smooth data processing.

Java Create and Write To Files

To create a file in Java, use the createNewFile() method from the File class. This method returns true if the file is successfully created, and false if it already exists.

Syntax


import java.io.File;
import java.io.IOException;

public class CreateFile {
  public static void main(String[] args) {
    try {
      File myObj = new File("filename.txt");
      if (myObj.createNewFile()) {
        System.out.println("File created: " + myObj.getName());
      } else {
        System.out.println("File already exists.");
      }
    } catch (IOException e) {
      System.out.println("An error occurred.");
      e.printStackTrace();
    }
  }
}

Output


File created: filename.txt

To specify a directory for file creation, use the full path with double backslashes for Windows or forward slashes for Mac and Linux.

To write to a file, use the FileWriter class and its write() method. Remember to close the file after writing using close():

Example


import java.io.FileWriter;
import java.io.IOException;

public class WriteToFile {
  public static void main(String[] args) {
    try {
      FileWriter myWriter = new FileWriter("filename.txt");
      myWriter.write("Files in Java might be tricky, but it is fun enough!");
      myWriter.close();
      System.out.println("Successfully wrote to the file.");
    } catch (IOException e) {
      System.out.println("An error occurred.");
      e.printStackTrace();
    }
  }
}

Output


Successfully wrote to the file.