In the past, I posted a few examples of implementing Messaging using J2EE and Spring. This post will describe how to use the Spring MessageListenerAdapter to enable any Java class to act as a Message Driven POJO. This can be used to enable existing applications to use Asynchronous Messaging. Follow these steps to run the... more »

Previously, I wrote a post describing the use of Apache Axis to create and consume Web Services from Java. In this post, I will describe how to use JAX-WS to create and consume web services. I used Glassfish application server for this application. The Web service and the Web Service client are both web applications.... more »

In the past, I wrote a post on how to implement Web Services using JAX-WS on Glassfish, and Apache Axis. In this post I will describe how to implement Web Services using the Spring framework and Apache Axis. The spring framework uses JAX-RPC API to help implement and access SOAP-WSDL based Web Services. The main components required for implementing and accessing Web Services in Spring are:... more »

In the past, I posted an example on how to use Displaytag with Struts and Spring, using Spring JDBC for data access(1, 2). In this post, I will describe how to do the same using Struts 2.0. The only major step that needs to be done here is to override the default Struts 2.0 OjbectFactory. Changing the ObjectFactory to Spring give control to Spring framework to instantiate action instances etc. Most of the code is from the previous post, but I will list only the additional changes here.... more »

In a previous post, I described how to implement Messaging in Java EE 5 using annotation. This post is an extension of that post to describe how to implement Messaging in Java EE 5 using a deployment descriptor. To implement this, you can use the same client that was described in the other post. The only change needed is in the MDB part. Here's how to implement a Message Driven bean using the deployment descriptor.... more »

Google Guice is an open source Dependency Injection framework from Google. Guice is based on annotations and generics unlike Spring which depends on XML of Java for wiring dependencies. Guice injects constructors, fields and methods (any methods with any number of arguments, not just setters). Guice provides support for custom scopes, static member injection, Spring as well as Struts 2.x integration and AOP Alliance method interception. Guice is available at Google Code. You can find the User guide and Javadocs from there. This post describes how I implemented a simple Web application using Guice. For injecting dependencies into Servlets, I used a Listener (this idea was from Hani Suleiman in the Guice developer mailing list). Follow these steps to run the example.... more »

Direct Web Remoting (DWR), is an open source Java library that can be used to implement Ajax in Java web applications with minimal Javascript coding. Using DWR, we can invoke server-side Java methods from Javascript in the browser. DWR 2.0 introduces a new feature, dubbed "Reverse Ajax", using which server-side Java can "push" updates to the browser. In this post, I tried to use a simplistic web application that will demonstrate the use of DWR for "Reverse Ajax".... more »

JSON (JavaScript Object Notation) is a lightweight data-interchange format based on a subset of the JavaScript Programming Language. JSON object structure is built on two structures:... more »

Hibernate EntityManager implements the programming interfaces and lifecycle rules as defined by the EJB3 persistence specification. Together with Hibernate Annotations, this wrapper implements a complete (and standalone) EJB3 persistence solution on top of the mature Hibernate core. In this post I will describe how map native queries (plain SQL) using Hibernate Annotations. Hibernate Annotations supports the use of Native queries through the @NamedNativeQuery and the @SqlResultSetMapping annotations.... more »

Acegi Security uses the SecurityContextHolder object to store details of the current security context of the application. The SecurityContext holds the details of the authenticated principal in an Authentication object. By default the SecurityContextHolder uses a ThreadLocal to store these details, so that they will be available all methods in the current thread of execution.In order to obtain the Principal, you would use the following line... more »