package nl.amis.database;


import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Date;


public class Database  {


   private static Connection conn;
   private static final String HOST = "amisnt15";
   private static final String PORT = "1521";
   private static final String DATABASE = "LUDO";
   private static final String USER = "SCOTT";
   private static final String PASSWORD = "TIGER";
   private static String lock = "lock";
   private static int count = 0;
   
   /**
    * Very crude Database connection provider. It actually caches a single fysical database connection
    */
   private Database() {
     //
   }
   
   
   
   
   public static  Connection getConnection() throws SQLException {
      synchronized (lock) {
        if (conn == null || conn.isClosed()) {
          createConnection();
        }
        return conn;
      }  
   }
   
    public static void closeConnection() throws SQLException {
       synchronized (lock) {
         if (conn != null && !conn.isClosed()) {
          System.out.println("Closing connection");
           conn.close();
         }
       }
   }


  private static void createConnection() throws SQLException {
      try {
        Class.forName("oracle.jdbc.driver.OracleDriver");
        conn = DriverManager.getConnection("jdbc:oracle:thin:@" + HOST + ":" + PORT + ":" + DATABASE, USER, PASSWORD);
        System.out.println("Creating connection");
      }
      catch (ClassNotFoundException e) {
        System.out.println("Error loading driver: " + e.getMessage());
      }

  }
  
  public static  boolean test()  {
     Statement stmt = null;
     ResultSet rs = null;
  
     try {
     Connection con = getConnection();
     stmt = con.createStatement();
     rs = stmt.executeQuery("select * from dual");
     while (rs.next()) {
       System.out.println(rs.getString(1) + " <> " +  new Date());
     }
     } catch (Exception e ) {
       System.out.println("Error during test :" + e.getMessage());
       e.printStackTrace();
       return false;
     } finally {
       try {
         if (rs != null) rs.close();
         if (stmt != null) stmt.close();
         if (count++%5 == 0) closeConnection();
       }
       catch (Exception ex) {
         System.out.println("Error closing resultset or connection " + ex.getMessage());
         ex.printStackTrace();
       }
     }
     return true;
  }
  
  
//  public static void main(String[] args) {
//    Timer runner = new Timer(false);
//    DatabaseTesterTask  pt = new DatabaseTesterTask();
//    runner.schedule(pt,100,100);
//    Timer runner2 = new Timer(false);
//    DatabaseTesterTask  pt2 = new DatabaseTesterTask();
//    runner2.schedule(pt2,75,40);
//
//  }
//  

public static void main(String[] args) { 
   System.out.println(test()?"SUCCESS":"FAILURE");


}
  

  

    




}