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How to integrate Container security in a web application and propagate it to EJB Layer. Normally an enterprise application has a web tier and a business tier (Most probably EJB in the case of J2EE).The security requirments for such an application in general will be this "Only an authenticated and authorized user should be able to access the protected part of the application" This includes both dynamic (jsp pages) and static content like HTML files. If the user has the rights for the web page then based on his role he should be restricted to invoke an ejb method.That's even if he has access to a page he should be able to execute only those business operations for which his role is given access. To satisfy the above requirement we have to have security at 2 levels . One at the web container side and other at the ejb container side. The rest of the post explains how we can do that in JBoss 4.2.2 See my old post on securing an EJB. Once the EJB is secured, next step is to sec...

This post is a detailed description on how to use the database login module in JBoss with a J2EE Application. Scenario There is a EJB and we want to restrict the access to this ejb's method to an authenticated user having a particular role. The EJB is accessed from a standalone Java Client using Remote Lookup. Implementation The EJB is HelloSSB and the roles allowed are admin and user. First step is to write the EJB The source code is given below. This is a stateless session bean. package com.prem.ejb; import javax.annotation.PreDestroy; import javax.annotation.Resource; import javax.annotation.security.RolesAllowed; import javax.ejb.SessionContext; import javax.ejb.Stateless; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; import org.jboss.annotation.security.SecurityDomain; @Stateless @SecurityDomain ("helloworld") public class HelloSSB implements HellioIntf{ @PersistenceContext(unitName = "EntApp") EntityManager em; @Reso...

This is a very interesting and important difference between the Default settings of oracle and mysql isolation levels. Default Isolation Level for Oracle = READ COMMITED Defautl for MySQL = REPEATABLE READ

Introduction Using J2EE Container security is the first step towards designing a secure and portable J2EE application . The integration of Container security with an application is easy but requires some amount of knowledge and research. The main reason for this is various J2EE application server providers gives us only a limited amount of login modules by default. For example an Active Directory authentication is a standard requirement but not all J2EE Server vendors provide this.But many major vendors provide this login module . The bottomline is we may be required to write our own login modules for many standard services. Writing our own login module is not difficult .Writing a custom login module will not be covered in this post.This post is about integrating a DB login module to an application deployed in JBoss Server. In this post i am only giving the steps without eloborating on each of the steps. 5 Steps Identify the EJB that you want to secure. Add the annotation @Securitydoma...

Why do you need to load balance ? Here i will put forward the various options available for web load balancing. Before we go into that , let us first examine why do we need load balancing after all.Consider you develop a website and is available to the public.If the application is served from a single webserver then there is a high chance that the machine will be overwhelmed if the usage of the application increases. This may result in users experiancing unusually high response times or in worse case the machine can come to a halt.So you need some mechanism to distribute the load across different machines,without the client having to swich address. There are many widely used approaches. The most common ones are DNS based load balancing Software load balancing Hardware load balancing DNS based Load Balancing Here the DNS server is configured in such a way that it returns different IP addresses for various requests to the DNS server for a particular domain name. The DNS server may contai...

BEA has announced that they have reached an agreeement with oracle on the purchase of BEA by Oracle. I think BEA with its excellent application server Weblogic is the looser here. Oracle has their own Application server and SOA intergration platforms. So what are they going to do with Weblogic . Will they promote it or rename it ?

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This post shares some the factors that need to be considered while designing an application that is going to be accessed using a network having high latencies and low bandwidth. The post will also look at some of the important TCP level tuning factors. Symptom The application works well when accessed from some locations and from some other locations its very slow. Possible causes Network Issues Network is having high latency Bandwidth is very narrow Packet loss is high Application design related Multiple calls to server During design itself avoid using multiple server calls to fulfill a business process. From the client issue a single call to the server and let the server do the processing and return the desired objects in this call. Unnecessary transfer of data Re look your design /code and find out whether you are transmitting data that's not of importance to the client. Reduce all unnecessary data transfer to the client. Sending large chunks of uncompressed data Using differen...