Write double to a file using DataOutputStream : FileOutputStream « File « Java Tutorial

1. Java Tutorial
2. File
3. FileOutputStream

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

public class Main {
  public static void main(String[] args) throws Exception {
    String strFilePath = "C:/Double.txt";
    FileOutputStream fos = new FileOutputStream(strFilePath);
    DataOutputStream dos = new DataOutputStream(fos);
    double d = 1;
    dos.writeDouble(d);
    dos.close();
  }
}