Hi! I have a handler which perform queries against two databases. It sets them in to two Value Objects of type 'List' - ListA and ListB. I want to return these to my jsp page and process them in my jsp page. How can I do this. I am using MVC pattern - A jsp web form talking to Controller ...

Hi there!I am a beginner learning OO design patterns. I hope some of U expeienced guys can help me with this...I read that design patterns follow certain guidelines to identify objects. I had a brief look at patterns and got confused on where to start. Right now I am having the specifications ...

'provider implemented' APIs, like JMS for example, are very much 'interface' based. This is obviously a Good Thing as it removes any dependency on the actual implementation of the API.Underneath all of this though, a provider is actually implementing the API.So, lets say we have a ...

I like to know how RUP and OOAD are related?Is RUP a process which can be implemented by OOAD?

Hi!Some background before asking the question. I have so far worked only on 3 web applications. I am not an expert architect by any means, but I can usually identify patterns when I have to.But now, I have to design a totally different kind of system, and mind you, I do not have much ...

Hello !I have the need of the ServiceLocator pattern: I am currently using JMS intensively in my application through a session EJB that creates the topic factory (and so on) if not yet created as a class member. for instance I have a getTopic method that creates the topic if the class member is ...

Does anybody have a nice solution to passing arguments in Visitor pattern?The Visitor pattern is used to process an object structure (such as an abstract syntax tree) in many different ways without cluttering definitions of the objects with methods needed for all different kinds of processing. ...

I am learning Java and started my first Swing (standalone) application. While reading books and articles I found an article about two models that Java provides to base your application upon the MVC architecture: "Event Delegation" and "Observer/Observable".My question is, which one is better? ...

Are there any open source / free tools which can generate sequence diagram from java code ?Thanks in Advance Ratheesh

I'd like to get opinions on whether it makes more sense to implement a DataAccessObject (DAO) as a Stateless Session EJB or as a plain Java class. I'd prefer to implement it as a plain Java class as there is less overhead to create such an object and to locate it. As long as the connection to ...

Shopping Cart can be built either by using JSP session variable or by a stateful bean. Which one is better?

For example, I want to know what are subclasses of class Animal (here Dog, Cat) ?class Animal{ }class Dog extends Animal{}class Cat extends Animal{}Java reflection has a method to go up the tree getSuperClass(). How can I go down the tree ? If there isn't a method like that, please help me ...

Hi everyone,are there any good resources for learning more about programming models (or patterns, designs or what ever it's called) such as Singleton, Connector, Reactor, Observer etc? I believe these resources should make programming a lot easier and more structured.Thanks on ...

Hi all,I齰e got two different applications deployed at an unique weblogic server instance.If a user validates his access in one of those applicationes, he must have the possibility of "jump" to the other application without another validation.The EJBs are over the applications, they are deployed ...

Hi there!I am new to OOD and just started working on it. I hope some of U guys out there can clarify this basic doubt of mine.I am working on a example case study. I have gathered the requirements and specifications of the system and got stuck where I have to draw clas diagrams from them. We ...

Hi,I have a requirement wherein I need to search data from a database of huge volume(database DB2 is on mid range server). I need to comeup with a j2ee solution for the same. I need to display the results on-line.Any suggestions how we can retrieve data fastly from a huge database of not less ...

Hi all,I'd like to use the session facade for a Travel Agency Application.I'd like instead of a "fat" Session Bean that facades all EntityBeans, to split the business logics into 3 session beans,one for query info, one for booking and one for admin tasks.The matter is that, if I split the ...

Helo every one Can any one post fundaes on sharing a session on Multiple application servers.thanks in advance

I am working on a project where I use MVC in my application. I have used MVC in 2 ways:1. metode:My view class:public void update(Observable obs, Object obj) { if(obs.equals(model)) {if(obj.equals("Add User")) {userName = model.getUserName();password = model.getPassword();.. ...

hi, i need to develop a web application using j2ee patters. but i have no idea where to start. can i use the WAF which comes with petstore application or is there a place where i can download J2EE BluePrints Web Application Framework ("WAF) APIs. i know for using struts, i have to download ...

Hi,How do I access something that almost the whole application need to access (for ex a db connection)? Do I make it public and static? Or are there any better way?thanKS

Throughout all the J2EE examples I've seen, there is liberal use of ArrayList to contruct Collections. I've seen them in entity bean, session bean, struts action classes, all over the place. The JavaDocs for ArrayList say that they are NOT threadsafe, but give a threadsafe static method of ...

My problem is this: I have constructed a multi-threaded domain, of which one of the classes receives data from the network. I was taught that the domain classes and user interface classes should always be completely seperate (so multiple UI's can be built onto the same domain). The normal ...

Who has the experience with java.util.Observer and java.util.Observable ? Or Please help with 2nd parameter of method update(Observable o,Object arg)?

Hi all,I'm not sure whether this is the right forum to post this question to, but it seemed the most appropriate one to me.I have a standalone server application that clients can connect to on a certain port and interact with via sockets. The application uses the New I/O API to perform ...

HiI've got this senario that i need to model a UML diagram thus java code.the senario is simply this:There are two doctors in a practice and both take a daily clinic between 9:00 and 12:00. In addition, there are two receptionists, one of whom is part-time. Every patient is registered with one ...

here is a link of UML diagram i 've made , so please look at it and let me wt u think http://uk.geocities.com/aerohaith/mePhotoPage.htmlthe senario is here:There are two doctors in a practice and both take a daily clinic between 9:00 and 12:00. In addition, there are two receptionists, one of ...

As part of an assignment i have to come with some class diagrams for :Customer, MobilePhone , PackageCategory, Manufacturer, LatestPhones, CreditCardDetailsI have identified the attributes but need the methods to the follwing classes:Customer (Class Name)NameFull AddressTelephone NumberEmail ...

I encounter a OOP design problem at my work, I want toask your suggestion, so if you have some free time tospare, please help me out.Let's say I have three classes, A, AHolder, and B.class B extends Aclass AHolder is a container of A, it haveconstructors look something like this:AHolder(X x, Y ...

Hi,Well I will like to know about the Future of J2EE/EJB Technology especially viz-a-viz CORBA and .NET or any other parallel technology. Basically where it stands know and where it will in futureIt will be great if u could provide some links to the pages where any parallel study has been done ...

I want to start teaching myself the J2EE. I haven't got a server to play on. Should I look for cheap web hosting, buy a server? How hard is it to get a basic linux solution going?

Please i will gladly welcome suggestions(and what options there is) on how to backup and archive files in j2ee in windows

Hello,I'd like to model a realationship between, for instance, Customer and Profile entities in my Class diagram. And I'd like to include class attributes to communicate better my design. I intend to implement both entities as Entity EJB. Which of the following options is correct for ...

I have a fairly new team of developers to J2EE and I wanted to start them off with a short guide with some tips and best practices with J2EE. Is anyone familiar of such a guide?I found the following relatively useful http://www.theserverside.com/resources/article.jsp?l=TMCBestPractices , as ...

Hi,I'm getting started with J2EE but I can't start the J2EE server. I have to point out that I read the instructions in J2EE Tutorial 1.3 but I use J2EE SDK 1.4 Beta.. But it should work, shouldn't it? I don't expect the problem to be very serious but I'm a greener and can't solve it ...

Hi,I need to describe business requirement of a small billing system with UML, however, there is a lot of algorithms in the business requirement, I don't know I should use which diagrams to describe these algorithm. Is there anyone can help me?Thankschengb

When I try to run j2ee from my console I get the following message:Fatal Error: This J2EE SDK release runs only on Java 2 (JDK1.2 or later)I have j2sdk1.4.1_01 already installed so I don't understand why i get this error message.I have also set all my paths as follows:Path=C:\Program ...

hello everybody,is there anyone knows any free software that converts the jar file into UML class diagram.thank you in advance.

hi,i created a bunch of exceptions as an exacmpleclass MyException extends Exception{}and an interface to handel different ways to handel my exceptions sayinterface HandelInterface {handel(Exception exp);}i created a class that implements the interfaceclass GErrorHandel implements ...

Hi,I have two classes, singleton:public class Singleton { private static final Singleton INSTANCE = new Singleton(); protected Singleton() { System.out.println("Constructor of Singleton"); } public static Singleton getInstance() { return INSTANCE; }}And a tester:public class Test { public ...

I would like my subclassed JTree to be Observable and notify observers when the selection changes.But I can't extend from JTree and Observable at the same time.I must be braindead today or something, but please enlighten me :)

Hi there!I am re-writing a web application using design patterns, actually for learning DP.I am using JSP at front end. I have this doubt, which hopefully you experienced guys have answers for.1. I have a Controller class (servlet), which calls a appropriate Action class when some action takes ...

I need to communicate with a legacy system via XML over HTTP from the EJB layer. I created a custom solution for this on a previous assignment using Castor for the marshaling etc. and standard JDK classes for the opening the HTTP connection, posting etc. I am thinking of implementing a similar ...

I need to implement "user level" (available actions based on rights) functionality in my app .. this may affect everything from actions (menus, buttons) to available Fonts etc... suggestions? .. I was thinking of adding a "level" (int) to all my classes, and then creating a Factory that would ...

Hi there!I have been told that it is good to have an abstarct class and have some common methods in that class, so that its sub classes doesn't have to do them again. So, what I have done is -public abstract class EntityBean extends Object{protected ServletContext servletContext;protected ...

Hello Sir, I am working on an Enterprise Java Bean Application running on J2EE application server and use JavaMail API to send Emails throu' the application.... In the J2EE Deploytool the SMTP server is set to "smtp.roltanet.com" provided by ISP....and by connecting to Roltanet we are able to ...

What would you people suggest for 齡ood?methodologies for OOD design (and for non OOD)?I can only currently think of 3: UML, RAD and Xtreme programming, with UML obviously being the most popular and normally the most suited.UML is however rather bulky so are their anymore streamlined ...

i want to know how to enable ssl in weblogic6.1

hi there,class MainClass{class other1;class other2;...public void main(...)}other1 needs other2, other2 needs other3 and so on..,so you see, for instance i'm inside other2's function, from within, i need to use other1 ie,class other1 { public void afunction() {// needs other2 }}so what do i ...

Hi!AllI have developed a Chat Application which has to be put up at the Clientsplace over the intranet,i have developed it using the Avalon FrameWork for the server side and applet on the Client side.Everything works perfectly,the application also runs perfectly,im using the port 4000 for ...