Random number

package uns_p;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Calendar;
import java.util.Scanner;

public class Uns_P_C {
    public static void main(String args[]){

        String[] week_name = {"Mon.","Tue.","Wed.","Thu","Fri.","Sat.","Sun."};

        Calendar calendar = Calendar.getInstance();

        int year = calendar.get(Calendar.YEAR);
        int month = calendar.get(Calendar.MONTH) + 1;
        int day = calendar.get(Calendar.DATE);
        int hour = calendar.get(Calendar.HOUR_OF_DAY);
        int minute = calendar.get(Calendar.MINUTE);
        int second = calendar.get(Calendar.SECOND);
        int week = calendar.get(Calendar.DAY_OF_WEEK) - 1;

        @SuppressWarnings("resource")
        Scanner scan = new Scanner(System.in);

        System.out.println("Set label.");

        String val1 = scan.next();

        System.out.println("Please enter a numeric value.");

        int val = scan.nextInt();

        System.out.println("Output number of " + val);
        System.out.println("Output location of.");
        String str = scan.next();
        System.out.println("output : " + str);

        try{
              File file = new File(str);
              FileWriter filewriter = new FileWriter(file);

              filewriter.write("Date and time of creation : [ " + year
                      + " / " + month + " / " + day + " / " + week_name[week] + " ] Time to : "
                      + hour + ":");
              if (minute < 10){
                  filewriter.write("0" + minute);
              }else{
                  filewriter.write(minute);
              }
              filewriter.write("." + second + "s (JST 20:00 - 8:00 in CST)\n");
              filewriter.write("File dt : " + str + " \n");
              filewriter.write("Label : " + val1 + " \n");
              filewriter.write("Numeric value : " + val + " \n");

              filewriter.close();
            }catch(IOException e){
              System.out.println(e);
            }
        double D;

        for (int i = 0; i < val; i++){
            D = Math.random();
            System.out.println(D);
            try{
                  File file = new File(str);
                  FileWriter filewriter1 = new FileWriter(file, true);

                  filewriter1.write("Resalt : " + D + " \n");


                  filewriter1.close();
                }catch(IOException e){
                  System.out.println(e);
                }
        }
    }
}