/*
 * ConnectionPoolObject
 *
 * Modified: $Date$
 *
 * Author: Klaus Gotthardt
 *
 * Copyright (c) 1998-2001 Klaus Gotthardt
 * All rights reserved.
*/

import java.util.*;
import java.sql.*;

public class ConnectionPoolObject{
    public boolean DEBUG=true; 
	
 
    private Vector connections=new Vector();  // one row for each connection
    private Timer timer=null;
    private boolean isCont=true;
 
 /*   public ConnectionPoolObject() {
    }
*/

  public synchronized Connection getConnection(String driver,String url,String user,String password){
	   Connection con = takeFromPool(url,user);  // in pool
      if (con == null) { //   create new connection 
           try{
              Class.forName(driver).newInstance();
   		     con = DriverManager.getConnection(url,user,password);
              if (DEBUG) log("new       " + url+user);
          } catch (Exception ex) {
                log("Cannot create new connection " + url+user);
          }
      }
      return con;
   }


   public synchronized Connection takeFromPool(String url,String user){
     
      Connection con = null;
      String urlUser=url+user;
      int count = connections.size(); 
      for (int j=0; j<count; j++) { 
           Vector row = (Vector)connections.elementAt(j);
           if   ( ((String)row.elementAt(0)).equals(urlUser) ) {
               con = (Connection)row.elementAt(2);
               connections.removeElement(row);
               if (DEBUG) log("reused    " + urlUser);
               break;
           }    
      }
      return con;
   }
 
   public void startTimer(){
	   timer=new Timer();
	   timer.start();
   }

 
   public void stopTimer(){
	   isCont=false;
	   timer.interrupt();
   }

  public synchronized void putConnection(String url,String user,Connection con,int expTime){
      java.util.Date date1=new java.util.Date();
      java.util.Date expDate= new java.util.Date(date1.getTime() + expTime);
      String urlUser=url+user;
      Vector newRow = new Vector();
	   newRow.addElement(urlUser);  //  url and user
      newRow.addElement(expDate);  //  expiration date
      newRow.addElement(con);      //  connection
      connections.addElement(newRow);
     // if (DEBUG) log("put     " + urlUser);
  } 
  
  
   public synchronized void closeConnection(String url,String user){

      String urlUser=url+user;
	   Connection con = null;
      int count = connections.size(); 
      for (int j=0; j<count; j++) { 
           Vector row = (Vector)connections.elementAt(j);
           if   (((String)row.elementAt(0)).equals(urlUser))  {
               con = (Connection)row.elementAt(2);
               try {
                  connections.removeElement(row);
                  con.close();
                  if (DEBUG) log("close     "+urlUser);
               } catch (SQLException ex) {
                  log("<p>*** SQLException caught ***\n");
	            }
           }  
       }
  }

   
   public synchronized void closeAll(){
	   while(isCont){
	      int count = connections.size(); 
         for (int j=0; j<count; j++) { 
           Vector row = (Vector)connections.elementAt(j);
           Connection con = (Connection)row.elementAt(2);
           if (DEBUG) log("closeAll  "+(String)row.elementAt(0));
           try {
              connections.removeElement(row);
              con.close();
           } catch (SQLException ex) {
              log("<p>*** SQLException caught ***\n");
	        }
           
         } // end for    
       } // end while
     } // end
 


   private void log(String msg) {
       System.out.println(new java.util.Date() + " - ConnectionPoolObject: " + msg);
   }
 


   class Timer extends Thread{

	public synchronized void run(){
	   while(isCont){
	      try{
	         sleep(60*1000);
	      } catch(InterruptedException ex){
		      interrupt();
		      break;
	      }
			java.util.Date now=new java.util.Date();
	      java.util.Date expDate=new java.util.Date();
         // nowDate.getTime();
         // if (DEBUG) log("check");
         int j = connections.size(); 
         // for (int j=0; j<count; j++) { 
         while (j > 0) {
           j--;
           Vector row = (Vector)connections.elementAt(j);
           String urlUser = (String)row.elementAt(0);
           expDate=(java.util.Date)row.elementAt(1);
           Connection con = (Connection)row.elementAt(2);
           if ((now).after(expDate)) {
              if (DEBUG) log("expired   "+urlUser);
              connections.removeElement(row);
              try {
                con.close();
              } catch (SQLException ex) {
                log("<p>*** SQLException caught ***\n");
	           }
           } // end if
         }
         
         // } // end for    
       } // end while
     } // end run
  }  // timer

} //End of :