I am in the process of implementing a command pattern to abstract ejb access between client and server. In the command pattern I am implementing, I am using a Command object that gets passed through the Proxy/Business Delegate to the Facade, and to the correct ejb. I have written a ...

the model i need have 3layers:JSP+EJB+SocketServer, i know EJB can act as Socket Client(not Server),but the main problem is that i must use a .dll or .lib file(written in c) in EJB to packge the socket data.someone says EJB can use JNI while EJB Spec won't allow it, i dont't want to take the ...

Hi all I received message below when used Http://localhost:8000/ Error: 500Internal Servlet Error:java.lang.NoSuchMethodErrorat com.sun.web.security.SecurityInterceptor.setSSLAttributes(SecurityInterceptor.java:56)at ...

Hi all,1. I download this file ,I found that the size is 14.2 MB,but the size of web page is 14.9 MBI can setup the fileI use windws 2000But I can't see the default page of j2ee after " http://localhost:8000"I want know the size can influence run j2ee?2. J2ee can be intead Tomcat or JSWDK ...

Hi all,What should be a good design technique in order to allow a JSP page to present some list obtained from other layer of my application. I intend to leave only presentation logic in the JSP layer, while all data access will be in other layer. For example, I have a JSP page that will show ...

Hi there, I am very new to J2ee technology and am trying Account example which comes with Sun j2dskee server.I am using the Cloudscape database.I am able to deploy the application without any problem.But when I run the client I am getting the following error.In the server console:Can't find ...

Hi there,when I run the Account example in j2ee using cloudscape,i get the errorCan't find principle mapping information for the data source with the jindi name jdbc/Cloudscapeand in command prompt: getting rmi.remotexception:couldn't create entity bean.pls helpThanks-Devi ...

I am the beginner of J2EE, If I access the J2EE server, I need to type http://localhost:8000/the port is 8000, can I use the other port instead of 8000, for example use the common port 80 instead of 8000

Hi All,I am a lover of Java.I reside at TianJin City of china.The city have eight hundred million people,and a lot of people have be very interest at Java Technical and obtained Professional Certification of java.But their study is no convenience & want for infomation of Technical.The ...

Hi, please help me, i turn crazy!! I'm trying to create a cluster with weblogic 6.1. The documentation says that each member of a cluster MUST listen to the same port number.I start the first server and everything is OK.But when i start the second server, a shutdown sequence is initiated ...

In J2SDKEE1.2.1,I can find javax.rmi.PortableRemoteObject.class,but in J2SDKEE1.3,I can not find PortableRemoteObject.class.Who can tell me where is it?In developing EJB,the client code contains:" RemoteHome home=(RemoteHome)javax.rmi.PortableRemoteObject.narrow(obj,RemoteHome.class);"Does the ...

Posted this in the JMS Forum...Probably..I should ask people in this forumAnyone knows why I can't start the j2ee ..which I hope to use it as the JMS provider. I am trying to try the e.g. from JMS tutorial....But it seems that I can't start the j2ee in the first place 'cos error say that I ...

After installing J2EE and making all PATH lines needed in the autoexec.bat, i run j2ee :C:\j2ee -verboseand get error messages :"Insufficient environmental space" (16 times)"Syntax error" (3 times)"Insufficient environmental space" (1 time)"invalid command or filename" Is there anyone who had ...

Hi!I want to use MySQL with EJB. I know that J2EE supports two phase commit.As you might know, MySQL doesn't support transactions fully.I wondering if two phase commit concept in J2EE requires transaction support from database or it can manage transactions even if a database server doesn't ...

i am newbie to the j2ee and wirte a simple ejb jar file to depoly on jboss with no error message. beside, with a client hope to access test if my ejb jar could work correct, but i do not know how to run the client by typing java HelloClient (the client i worte)in commond line or spesify the ...

I am not sure this is the right forum but I think it is closest. I have some questions regarding the containers of the J2EE AppServer. 1. Is it possible to host multiple containers in AppServer in one JVM?2. Is it possible to develope my own container but follows the J2EE rules.3. What is ...

How is Command Pattern is light weight as compared to session fascade design pattern?

Greetings:I am attempting to compile an EJB test client using the Sun tools. I am running on a Red Hat Linux environment. My classpath is as follows:CLASSPATH=/home/work/research/jdk1.3.1_01and I am attempting to do the compile using compile.sh, which contains the following ...

Hi all,In one of the beanmanaged entity bean, the ejbStore is not called after ejbCreate. I am using wblogic 6.1 server. I've also coded similar types of entity bean and those are working perfectly.I am getting the following exception message when I call the create method from the ...

I'm trying to create a tag to implement templates. I'm using the PetStore as an example. I get to this point but I do not understand the message! Is not TagSupport implementing the Tag interface? The tag InsertTag extends TagSupport and calls super() in the constuctore?Can anyone help me with ...

Greetings:I am attempting to deploy a CMP bean on the J2EE reference server. Cloudscape is the database I am using.In all of the documentation and books that I have read, when you add such a bean to an application using the deploytool, in the deployment settings window you can create the ...

I have a question about the Observer patterne. I have tried to implement it im my application but without result. First my idea was to save all the client Object references in A linked List in a bean on the server. Then each time a certain event ocurs on my server I will call a method fire() ...

I am new in the J2EE world so I have no feeling which objects should be implemented as EJB objects and which should be notmal objects. Are there any criterions for that? Thanks in advance.

Hi, i'd like to utilize the J2EE capabilities for user management in my web application. I had a look at the Tomcat security sample which provides automatic login whenever a user tries to access a protected resource. This looks promising but the only drawback here is how the list of users is ...

Hi, Startup classes are very necessary one in some situations.Support for the startup classes provided by weblogic or orionserver or other appservers are different..I mean that startup classes meant for one appserver can not used in other appserver without much changes made to it.Whether there ...

Hello dear j2ee community !How can I configure the j2ee server such that when someone type http://localhost/~username he is directly redirected to the public_html directory of the username ?I know that we can do this with tomcat (adding something like that in the server.xml file: <Listener ...

After going through the book ,UML Distilled,and some other sites, i struck with some doubts. The major concerns are1. Regarding the steps or sequence of OOAD model .For the OOAD approach,I assume that the steps to be followded are i) Usecase ii) Problem domain identification iii) Sequence ...

HiI am currently investigating the setup we'll need to develop java apps - we're looking to develop multi-tier applications using jsp,servlets and ejb's. We are however currently tied into using Microsoft IIS webservers. From what I can gather we therefore have no choice but to purchase an ...

I feel that while designing a J2EE application, using the Java Data Objects alongwith Entity beans is somewhat redundant. Is it so or there is any reason behind this architecture?

A servlet in WAR_A talk with a browser ,the servlet record some status,such as username,login success or failed.Then,the browser go to another servlet in WAR_B,How can the servlet in WAR_B get the status made by the servlet in WAR_A a moments ago.In some application on web,such as WAR_A work ...

Dear all,I have tried to use the method File.delete() to delete a file. However, when I call this method in my EJB, I got the the exception "access denied [FilePermission abc.txt delete], can I delete a file using EJB in J2EE or use JSP to delete files?Please help me, thank you ...

I have a question as follows:I use a SessionBean to invoke two EntityBean's methods,and i want these two methods in one transaction context. I mean i want them rollback or commit together.for example :Session bean method sessionTest(),invoke EntityBean methods test1()and test2(),if test1() is ...

I have develop a web application follows J2EE design pattern like Front Controller and others in J2EE Petstore Example. I'm not using any EJB,only serlvet , JSP and Javabeans and implement Command Pattern in the framework.It has a entry form and after i submit the form , the controller servlet ...

Hello, I've been developing JSP's and Servlets, and am just getting in to the realm of EJB's... I am writing a data-driven system in which I want to query method names from a DB and invoke them on my Enterprise bean. I've been using a simpler version of the same code (not using the ...

Microsoft is saying they developed the J2EE Pet Store blueprint application using .NET and they claim it took 1/3rd of the code and runs 28 times faster on the same hardware configuration (compared to the same J2EE application running on Oracle 9i). http://www.gotdotnet.com/team/compare/Does Sun ...

Hi all, unfortunatley there is no forum for project management issues, so maybe I will bother some of you with non-technical questions:Is there any learning material e.g. books, forums, newsgroups, tutorials related to the topic of project managment in J2EE-Development? I'm particularly ...

Hi:Im trying to monitor resources (memory leak, cpu usage, etc) used by Jakarta Tomcat.I have tried RUE ( http://rue.nolimits.ro) and JInsight ( http://www.alphaworks.ibm.com/tech/jinsight) with no success (I think Jinsight only works for Websphere).Does anyone has been able to monitor Tomcat in ...

Hi Expertises,Any idea to improve my poor code for detecting stale homes... or no way to detect it? I got exception after i restart/re-deploy ejbs.I spent big effort on this issue because it gives me significant benefit on performance.thx/** * This is a utility class for obtaining EJB ...

I would like to Deploy EJB 2.0 specific beans and would like to have a appropriate deployment tool for that purpose latest J2EE SDK available for download now at the following URL: http://java.sun.com/j2ee/j2sdkee-beta/index.html. was not serving the purpose. Does this deployment tool come ...

Hi there,I've got two j2ee applications that are running on two different machines. In application A, some ejbs need to talk to the ejbs living in application B. But I don't know how an EJB can look up another EJB running in another computer?When a stand-alone java app client tries to talk to ...

I have downloaded J2EE and I am trying to get started with it. I got the tutorial and I am using it to start learning how to use J2EE. There is a problem though. I am at the first application, the conversion stuff. I didn't manage to use ant to compile my files, but I did it with javac. ...

The problem is that the Session bean cannot get the chinese character from JSP.I have set<%@ page language="java" contentType="text/html;Big5"%> in JSPwhen I invoke the Session bean by following code/************************************************************InitialContext ctx_forum=new ...

should ejbs call other ejbs or should the middle tier control all ejb communication

What is the best way to package classes that are common across separate EJB jar files? IE, i have an object that is passed between the 2, or a utility that is used by both. Is it customary to package the classes within the EJB jar file? This seems silly to me becausenow you have 2 versions of ...

Hi,I want to run different versions of EJBs on the same application server instance. My idea is to have a component which provides access to these EJBs depending on the desired version. The idea behind this is to test different versions of EJBs (e.g. unit testing and integration testing on the ...

I'm going to implement the front controller pattern. As it is implemented in the blueprints (Pet Store), requestmappings.xml and screendefinitions.xml are only read upon start up. Thus, the web application has to be restarted to carry out changes.I'd like the possibility to perform changes to ...

HiWhat is the difference between the Factory and Singleton pattern.Can we use a singleton (pattern) class to create other object instances and return them.What are the advantages and disadvantages for using the Singleton pattern here.Or do we have to use only a factory (pattern) class to do the ...

I have to use job scheduler for creating agent. Is there any J2EE time scheduling API are there for it. I am using Weblogic, in 6.1 Time Services are deprecated. And they are recommeding got FLUX job scheduler.By using FLUX can i be able to deploy my application on any J2EE servers.Is there any ...

Hi,I have to create Agents that perform the job on regular interval. I am going to use JMS for sending results back to the client. My need is to run this scheculed on the weblogic application server. Does any one have createed or have idea how to proceed can give their valuable ...

We wish to connect fat clients (in our case Powerbuilder) to a J2EE environment (Weblogic). We also need to make some of the calls from the fat client non-blocking (asynchronous). With many clients, JMS was rejected as a mechanism.Our first solution, which works as a prototype, was to package a ...