The second solution is better because you separe the business layer to the jdbc layer. An other reason is that the application is safetly. Think about the ResultSet and the Statement objects ... wath happen to the ResultSet when the connection is closed? What happen to the ResultSet when you execute an other SQL query with the same Statement? And so on...

I will suggest you to put each object in a LinkedList, that is a Collection as the Vector class but much better for save a big number or Object. With a LinkedList object you can do the same:


ListIteretor iter = linkedListoObject.listIterator();



and than you can iterate through your object ...

iter.hasNext();

iter.next();

iter.previous();

....




That is a good solution.

Bye bye and for other problems I'm ever here, Aron

The answer really depends on exactly what your app needs to do, although I'm not sure how you plan to put the data into another ResultSet unless it something like a cached ResultSet.

However, that may all be moot. People are often derided when they say redesign your app to deal with fewer records at a time, but you have a very real issue here of how much memory is available. I've seen apps in the past chug away trying to read all the data in one pass, only to eventually die with an "out of memory" error.

I think that if you want separate the business layer for the persistent layert (jdbc layer) the second solution is the better.

I done the same. For each table in the DB i programed a class with all db-attributes(**) and when I must search more record I programed a finder class that returned me a LinkedList. In this method i execute a Statement,iterate the ResultSet, create an object(**), puit the object in the LinkedList. and returned the LinkedList.

	public LinkedList findOrderByMember(Long id) throws PersistentException, ExceptionDataNotFound 
	{
		LinkedList resultVector = new LinkedList();
		Order order = null;
		
		try 
		{
			String qry = "SELECT * FROM ORDER WHERE MEMBER = " + id; 
			Statement stmt = this.pl.getConnection().createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
	    	              ResultSet result = stmt.executeQuery(qry);
	    	              boolean found = false;
	    	
	    	              while (result.next()) 
			{
				found = true;
				
				Long price = Converter.getLong(result.getBigDecimal(1));
				Long pieces 	= Converter.getLong(result.getBigDecimal(2));
				String productId 	= result.getString(3);
				String productName  = result.getString(4);
	
				order = new Order(pl, id, piece, productId, productName);

				resultVector.add(order);
			}
			if (!found)
				throw new ExceptionDataNotFound(PersistentException.RECORD_NOT_FOUND);
		    
			return resultVector;
		} 
		catch (SQLException ex) 
		{
			System.out.println("In PersistentObjectFinder.findOrderByMember(): ");
			
			System.out.println("SQL State: " + ex.getSQLState());
			System.out.println("Error Code: " + ex.getErrorCode());
			ex.printStackTrace();
			
			throw new ExceptionDataNotFound(PersistentException.RECORD_NOT_FOUND);
		}


	}

Bye Aron

Second way is best.