Java tutorial
import java.io.ByteArrayOutputStream; import java.io.DataOutputStream; import java.io.FileOutputStream; import java.io.IOException; public class Main { public static void main(String args[]) throws IOException { int howMany = 20; ByteArrayOutputStream bout = new ByteArrayOutputStream(howMany * 4); DataOutputStream dout = new DataOutputStream(bout); for (int i = 0; i <= 20; i++) { dout.writeInt(i); } FileOutputStream fout = new FileOutputStream("fibonacci.dat"); try { bout.writeTo(fout); fout.flush(); } finally { fout.close(); } } }