New to J2EE Pls Help in some basic Problems

Question

Hello Friends! This is Anand. I had started working in J2EE recentelly. In start we r using J2EE server. but later we deployed same java beans on iPplanet server. it gives some problems. So can anybuddy told me answers of my following questions-
1) What is basic difference in J2EE server and iPlanet.
2) Is iPlanet is reliable server or suggest some reliable server(shoule i use Oracle 9i)
3) Sometimes i come accross an error - Marshal Error or UnMarshal error. i cant understand what actually
i have to change in my EJB.
so pls guide me.
- Thanks in advance

Answer 1

Hello Friends.
Thanks for quick replay.
I am using J2EE server means which comes with J2EE 1.3
Now I am using MySql and iPlanet Server. In that i always face a problem with database and i have to restart database server-
Too many connection
I am using a helper class for database connection. So if there is any better way to connect to database pls suggest
(We are not using CMP Entity Beans)
The class is as follows
public class help
     public String server="localhost";
     public static String database="system";
     public String driver="org.gjt.mm.mysql.Driver";
     public String user="root";
     public String dns="jdbc:mysql://"+server+":3306/"+database+"?user=root&password=";
     String passward="";
     String password="";
     public help(){
public class help10 extends help
public Connection c = null;
public Statement st = null;
public ResultSet rs = null;
     public help10()
     public void connect()
          try
               Class.forName(driver);
               c=DriverManager.getConnection(dns,user,passward);
               st=c.createStatement();
          }catch(Exception ex){e.printStackTrace();}
public void disconnect()
          try
               if(c!=null)
                    c.close();
          }catch(Exception ex){e.printStackTrace();}
          c = null;
}