Write UTF String, integer and double with DataOutputStream : FileOutputStream « File « Java Tutorial

1. Java Tutorial
2. File
3. FileOutputStream

import java.io.BufferedOutputStream;
import java.io.DataOutputStream;
import java.io.FileOutputStream;

public class Main {
  public static void main(String[] argv) throws Exception {
    FileOutputStream fileOut = new FileOutputStream("data.txt");
    BufferedOutputStream buffer = new BufferedOutputStream(fileOut);
    DataOutputStream dataOut = new DataOutputStream(buffer);
    dataOut.writeUTF("Hello!");
    dataOut.writeInt(4);
    dataOut.writeDouble(100.0);
    dataOut.close();
    buffer.close();
    fileOut.close();
  }
}