How do I create a file and write to it?

java

file-io

java-7

try-with-resources

byAlex Kataev·Feb 12, 2025

Create and write to a file with the File class and FileWriter in Java:

import java.io.*;

public class SimpleFileWriter {
    public static void main(String[] args) {
        String fileName = "example.txt";
        String content = "SomeContent";
        
        try {
            File file = new File(fileName);
            if (file.createNewFile()) {
                FileWriter writer = new FileWriter(file);
                writer.write(content); // Spilling ink onto the parchment
                writer.close(); // Stashed the quill! 
            } // Else, the file already exists; don't want to accidentally summon a demon by overwriting files, do we?
        } catch (IOException e) {
            // A wild error has appeared!
            e.printStackTrace();
        }
    }
}

Advanced file writing: text files in Java 7+

Java 7 introduced some cool kids on the block: java.nio.file for easy file operations.

import java.nio.file.*;
import java.io.IOException;
import java.util.*;

public class AdvancedFileWriter {
    public static void main(String[] args) {
        Path pathToFile = Paths.get("example.txt");
        List<String> lines = Arrays.asList("Java is love,", "Java is life!");

        try {
            Files.write(pathToFile, lines, StandardCharsets.UTF_8,
                        StandardOpenOption.CREATE, StandardOpenOption.APPEND);
            // Who needs coffee when you got Java.
        } catch (IOException e) {
            // Debugging—it's like being the detective in a crime movie where you are also the murderer.
            e.printStackTrace();
        }
    }
}

Binary files: Efficiently managing bytes

For binary data, such as image or video files, OutputStream is your wingman.

import java.io.*;

public class BinaryFileWriter {
    public static void main(String[] args) {
        String fileName = "example.bin";
        byte[] data = new byte[]{ 0x4a, 0x61, 0x76, 0x61 };

        try (FileOutputStream fos = new FileOutputStream(fileName)) {
            fos.write(data); // Java in bytes... Isn't it beautiful?
        } catch (IOException e) {
            // IOException: Because users always close their streams.😂
            e.printStackTrace();
        }
    }
}

Simplified file writing: Apache Commons IO & Google Guava

Writing files has never been easier with the help of Apache Commons IO and Google Guava.

Apache Commons IO

import org.apache.commons.io.FileUtils;
import java.io.File;
import java.io.IOException;

public class CommonsFileWriter {
    public static void main(String[] args) {
        File file = new File("example.txt");
        String data = "Easy peasy lemon squeezy!";
        
        try {
            FileUtils.writeStringToFile(file, data, "UTF-8");
            // Writing files is easier than peeling a banana!
        } catch (IOException e) {
            // Welcome to Catch statement. Enjoy your stay!
            e.printStackTrace();
        }
    }
}

Google Guava

import com.google.common.io.Files;
import java.io.File;
import java.nio.charset.StandardCharsets;

public class GuavaFileWriter {
    public static void main(String[] args) {
        File file = new File("example.txt");
        String data = "Simplified I/O with Google Guava!";
        
        try {
            Files.write(data, file, StandardCharsets.UTF_8);
            // Guava makes I/O as simple as ABC.
        } catch (IOException e) {
            // Catching exceptions is a hobby, isn't it?
            e.printStackTrace();
        }
    }
}