VL-Programmieren/VL12/Aufgabe01/Aufgabe01.java

package VL12.Aufgabe01;

import java.io.File;
import java.io.FileWriter;
import java.util.Random;

/**
 * Vorlesung 12 - Ein- und Ausgabe - Aufgabe 1
 * @author Sebastian Brosch
 * @see https://gitea.hb.dhbw-stuttgart.de/sebastianbrosch/VL-Programmieren/src/branch/main/VL12/Aufgabe01
 */
public class Aufgabe01 {
  public static void main(String[] args) {
    final String COLUMN_SEPARATOR = "#";
    final int START_KUNDENNUMMER = 100000;
    int cntDataSets = 0;

    do {
      try {
        System.out.print("Anzahl der Datensätze: ");
        cntDataSets = Integer.parseInt(System.console().readLine());

        // only positive numbers are valid.
        if(cntDataSets <= 0) {
          System.out.println("Bitte geben Sie eine gültige Anzahl ein (min. 1)!");
        }
      } catch(NumberFormatException e) {
        System.out.println("Es wurde keine gültige Anzahl Datensätze eingegeben!");
      }
    } while(cntDataSets <= 0);

    StringFeld namen = new StringFeld(getPathFromPackage() + "/input/Nachnamen.TXT");
    StringFeld strassen = new StringFeld(getPathFromPackage() + "/input/Strassen.TXT");
    StringFeld vornamen = new StringFeld(getPathFromPackage() + "/input/Vornamen.TXT");
    StringFeld postleitzahlen = new StringFeld(getPathFromPackage() + "/input/PLZOrt.TXT", " ", 0);
    StringFeld orte = new StringFeld(getPathFromPackage() + "/input/PLZOrt.TXT", " ", 1);

    // create missing output folder.
    final String folderOutput = getPathFromPackage() + "/output/";
    final File fileOutputFixedWidth = new File(folderOutput + "output-fixed-width.txt");
    final File fileOutputSeparator = new File(folderOutput + "output-separator.txt");
    final File parentFolder = fileOutputFixedWidth.getParentFile();

    if(null != parentFolder) {
      parentFolder.mkdirs();
    }

    try {
      FileWriter outputFixedWidth = new FileWriter(fileOutputFixedWidth);
      FileWriter outputSeparator = new FileWriter(fileOutputSeparator);

      for(int i = 0; i < cntDataSets; i++) {
        int kundennummer = START_KUNDENNUMMER + i;
        int hausnummer = getRandomNumber(1, 99999);
        int umsatz = getRandomNumber(500, 2000);

        outputFixedWidth.write(String.format("%-6d", kundennummer));
        outputFixedWidth.write(String.format("%-20s", namen.get(i, 20)));
        outputFixedWidth.write(String.format("%-20s", vornamen.get(i, 20)));
        outputFixedWidth.write(String.format("%-20s", strassen.get(i, 20)));
        outputFixedWidth.write(String.format("%-5s", hausnummer));
        outputFixedWidth.write(String.format("%-5s", postleitzahlen.get(i)));
        outputFixedWidth.write(String.format("%-20s", orte.get(i, 20)));
        outputFixedWidth.write(String.format("%-5s", umsatz));
        outputFixedWidth.write("\n");

        outputSeparator.write(String.format("%d" + COLUMN_SEPARATOR, kundennummer));
        outputSeparator.write(String.format("%s" + COLUMN_SEPARATOR, namen.get(i)));
        outputSeparator.write(String.format("%s" + COLUMN_SEPARATOR, vornamen.get(i)));
        outputSeparator.write(String.format("%s" + COLUMN_SEPARATOR, strassen.get(i)));
        outputSeparator.write(String.format("%d" + COLUMN_SEPARATOR, hausnummer));
        outputSeparator.write(String.format("%s" + COLUMN_SEPARATOR, postleitzahlen.get(i)));
        outputSeparator.write(String.format("%s" + COLUMN_SEPARATOR, orte.get(i)));
        outputSeparator.write(String.format("%d", umsatz));
        outputSeparator.write("\n");
      }

      outputFixedWidth.close();
      outputSeparator.close();
    } catch(Throwable e) {;}

    System.out.println("Die Testdaten (" + cntDataSets + " Zeilen) wurden erzeugt.");
  }

  /**
   * Method to determine a random number from a certain range.
   * @param start The first number of the range.
   * @param end The last number of the range.
   * @return A random number from a certain range.
   */
  private static int getRandomNumber(int start, int end) {
    return (new Random()).nextInt(end-start) + start;
  }

  /**
   * Method to get the relative path based on the package name.
   * @return The relative path of the package based on the package name.
   */
  private static String getPathFromPackage() {
    return Aufgabe01.class.getPackageName().replace(".", "/");
  }
}