Lets get started

Below we will show you how to get integrate GI with Spring's MVC.

Before we integrate with GI, we need to verify Spring in a 'stock' MVC/JSP environment. See the spring tutorial Spring MVC step by step. It's important that you understand this example because we will use this specific application as a basis for GI integration.

Our starting points are the latest and greatest versions of Spring, Xstream and GI. Our use case requires that we display a price list of products and modify the prices by entering a validated percentage the system will apply to all prices. Then, the price system will validate the percentage input and display error messages if the percentage is invalid.

Spring setup

Customizing build for your environment

Review the resources section below to see what components you will need to install on your system. At a minimum you will need Java (1.4.2 or higher), Ant (1.6.2), Spring (1.2.8) and Tomcat (5.5.x) and your favorite IDE. You'll also need to customize the build.properties and log4.properties files for your environment. See the Spring MVC step by step tutorial and ensure you can view the JSP pages.

Spring Architecture

    •     Spring's View layer
    •     Spring configuration in detail

Take a look at the application context defined at src/main/Webapp/Web-INF/gi2spring-servlet.xml. Here we can see the two controllers established for the two actions (list products and increase products). Both have the product service (productManager) passed to them. The price increase controller also has a form and a validator associated with it. Note that the form and validator are POJOs (Plain Old Java Objects). There is no dependency between them and the Spring framework or JSP layer. Also defined here are the mapping between the controller names and the URLs. We made a change to the Spring example application controllers. We made the success view and form view values configurable as opposed to hardcoded. This is a best practice for Spring controllers in any event. It will become important shortly as we configure Spring to interoperate with GI.


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One last configuration to examine is the view resolver


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The view resolver is a plugin that tells Spring how to render the output from a controller. Here the view properties returned from the controller ("hello" and "priceincrease" ) get mapped to actual JSPs ("/Web-INF/jsp/hello.jsp" and "/Web-INF/jsp/priceincrease.jsp") . The view class is the component that in turn actually takes the output from the controller and renders it.