import java.io.*;
import java.util.zip.GZIPOutputStream;

public class GZipFile {
    public static void main(String[] args) {
        String sourceFile = "example.txt";
        String gzippedFile = "example.txt.gz";

        try {
            FileInputStream fileInputStream = new FileInputStream(sourceFile);
            FileOutputStream fileOutputStream = new FileOutputStream(gzippedFile);
            GZIPOutputStream gzipOutputStream = new GZIPOutputStream(fileOutputStream);

            byte[] buffer = new byte[1024];
            int bytesRead;
            while ((bytesRead = fileInputStream.read(buffer)) != -1) {
                gzipOutputStream.write(buffer, 0, bytesRead);
            }

            fileInputStream.close();
            gzipOutputStream.finish();
            gzipOutputStream.close();

            System.out.println("File " + sourceFile + " was compressed to " + gzippedFile);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}