/* Written by Jen Chen
   Updated on June, 2005.
   Copyrighted by Jen Chen
 	An example to manipulate the fields in a csv file then redirect the result to
a tab delimited file.
*/
import java.io.*;
import java.util.*;

public class File_Writer {
  public static void main(String[] args) throws IOException{
    File output = new File("output.txt");  //create a new file for output.
    output.createNewFile();  //create a new file if necessary.
    BufferedWriter out = new BufferedWriter(new FileWriter(output));
    String fname = "Details.csv";
    fname = fname.trim();

    BufferedReader in = null;
    try{
      in = new BufferedReader(new FileReader(fname));
    }
    catch(Exception e){
      System.out.println("Unable to open the specified file!");
      System.out.println(e);
      System.exit(1);
    }
    StringTokenizer st;
    int total = 1, qty = 0;
    double price_unit = 0., sum = 0.;

try{
  in = new BufferedReader(new FileReader(fname));
  String  line = in.readLine(); //read into the column headers.

String st3 = "---------------------------------------------------------------------";
System.out.println(st3);
System.out.printf("%-35s%-15s%-10s%-20s","Description","Unit price","Quantity","Total");
System.out.println(st3);

  out.write(st3 + "\n"); //write the column headers to the output file.
  out.write("Description\tUnit Price\t\tQuantity\tTotal" + "\n"); //write the column headers to the output file.
  out.write(st3 + "\n"); //write the column headers to the output file.

  line = in.readLine(); //read into the first record.

  while(line != null){
    st = new StringTokenizer(line, ","); //Tokenize the string..
      String st2 = (String) st.nextToken();    //the Details.csv file. (it is String, thus it can't be PARSE!)
      st2 = st.nextToken(); //read the next token.(the 2nd field)
      st2 = st2.trim(); //remove all blank spaces; if there is any.

        System.out.printf("%-35s$",st2); //print the product's name. (2nd field)
        out.write(st2 + "\t");  //write the product's name to the output file.
        st2 = st.nextToken();  //read to the next token (the 3rd field).
        price_unit = Double.parseDouble(st2);
        System.out.printf("%5s",price_unit); //Assign 5 spaces to this string; then print the string right-aligned.

        st2 = st.nextToken(); //read into the next token. (the 4th field)
        qty = Integer.parseInt(st2);
        System.out.printf("%12s",qty); //Assign 12 spaces to this string; then print the string right-aligned.
        out.write("$" + st2 + "\t\t");  //write the per unit price to the output file.

        sum = price_unit*qty;
        System.out.printf("%15.2f\n",sum); //Assign 15 spaces to this double value; then print the string right-aligned.
        out.write(qty + "\t$" + sum + "\n");  //write the quantity & the sum to the output file.
    line = in.readLine(); //read into the next record.
    }
}
catch(Exception e){
  System.out.println(e);
  System.exit(0);
  }
  out.close();  //close the output file so that its contents will be written to the output file.
  }  //end of main()
}  //end of class File_IO5{}