Java/Hibernate/Hibernate Utility

Hibernate Utility

   <source lang="java">

///////////////////////////////////////////////////////////////////////// package util; import org.hibernate.HibernateException; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; public class HibernateUtil {

 public static final SessionFactory sessionFactory;
 static {
   try {
     // Create the SessionFactory from hibernate.cfg.xml
     Configuration config = new Configuration().configure();
     sessionFactory = config.buildSessionFactory();
   } catch (Throwable ex) {
     // Make sure you log the exception, as it might be swallowed
     System.err.println("Initial SessionFactory creation failed." + ex);
     throw new ExceptionInInitializerError(ex);
   }
 }
 public static final ThreadLocal session = new ThreadLocal();
 public static Session currentSession() throws HibernateException {
   Session s = (Session) session.get();
   // Open a new Session, if this thread has none yet
   if (s == null) {
     s = sessionFactory.openSession();
     // Store it in the ThreadLocal variable
     session.set(s);
   }
   return s;
 }
 public static void closeSession() throws HibernateException {
   Session s = (Session) session.get();
   if (s != null)
     s.close();
   session.set(null);
 }

}

/////////////////////////////////////////////////////////////////////////

package util; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.Statement; import java.util.ArrayList; /**

* @author joeyin
*  
*/

public class ConnectionUtil {

 static Connection conn = null;
 private static Statement st = null;
 public static void openConnection() {
   try {
     Class.forName("org.hsqldb.jdbcDriver");
     System.out.println("Driver Loaded.");
     conn = DriverManager.getConnection("jdbc:hsqldb:mem:testdb", "sa", "");
     System.out.println("Got Connection.");
     st = conn.createStatement();
   } catch (Exception e) {
     System.err.println("Got an exception! ");
     System.err.println(e.getMessage());
     e.printStackTrace();
     System.exit(0);
   }
 }
 public static String[] select(String sql) {
   ArrayList data = new ArrayList();
   try {
     ResultSet rs = st.executeQuery(sql);
     while (rs.next()) {
       data.add(rs.getString(1));
     }
   } catch (Exception e) {
     System.out.println(sql);
     e.printStackTrace();
   }
   if (data.size() == 0) {
     return new String[0];
   }
   return (String[]) data.toArray(new String[data.size()]);
 }
 public static void update(String sql) {
   try {
     st.executeUpdate(sql);
   } catch (Exception e) {
     e.printStackTrace();
     System.out.println(sql);
     //      System.exit(0);
   }
 }
 public static void closeConnection() {
   try {
     conn.close();
     System.out.println("Connection closed.");
   } catch (Exception e) {
     e.printStackTrace();
   }
 }

}

      </source>