// Programm 7-5g: BSP_ROOT/meinewebapp/WEB-INF/classes/muster/GaestebuchAendern.java
package muster;

import java.sql.*;
public class GaestebuchAendern {
  ResultSet rs; Statement s;
  public GaestebuchAendern() {
    try {
      Class.forName("org.gjt.mm.mysql.Driver"); 
      Connection c = DriverManager.getConnection("jdbc:mysql://localhost:3306/jdbcbuch");
      s = c.createStatement();
    }
    catch (Exception ex) {}
  }
  public Object setAnzeigen(String gnr) {
    try {
      rs = s.executeQuery("SELECT * FROM Gaestebuch WHERE gnr LIKE '" + gnr + "'");
      rs.next();
      return rs;
    }
    catch (Exception ex) { return null; }
  }
  public Object setNeu() {
    try {
      String gnr = "gb_"; 
      for (int i = 0; i < 25; i++) 
        gnr += (char)(int) (Math.random() * 26.0+ 'A');
      s.executeUpdate("INSERT INTO Gaestebuch(gnr) VALUES('" + gnr + "')");
      return setAnzeigen(gnr);
    }
    catch (Exception ex) { return null; }
  }
  public String getGnr() {
    try { return rs.getString("gnr"); }
    catch (Exception ex) { return null; }
  }
  public String getMotto() {
    try { return rs.getString("motto"); }
    catch (Exception ex) { return null; }
  }
  public String getText() {
    try { return rs.getString("text"); }
    catch (Exception ex) { return null; }
  }
  public String getKontakt() {
    try { return rs.getString("kontakt"); }
    catch (Exception ex) { return null; }
  }
  public Object setAendern(String gnr, String motto, String kontakt, String text) {
    try {
      String sql = "UPDATE Gaestebuch " + 
                   "SET motto='" + motto + "', kontakt='" + kontakt + "', " + 
                   "text='" + text + "' WHERE gnr LIKE '" + gnr + "'";
      return "" + s.executeUpdate(sql);
    }
    catch (Exception ex) { return null; }
  }

  public Object setLoeschen(String gnr) {
    try {
      String sql = "DELETE FROM Gaestebuch " + "WHERE gnr LIKE '" + gnr + "'";
      return "" + s.executeUpdate(sql);
    }
    catch (Exception ex) { return null; }
  }
}