Choose an IoC Container

As we discussed, WebWind does NOT manage the web components but requests all from IoC container. WebWind supports two build-in IoC container: Guice and Spring.

All methods with @Mapping defined in JavaBeans which are managed by IoC container will be scanned and hold by WebWind. For example, define such class which contains two methods with URL mapping:

public class Blog {

    @Mapping("/hello/$1")
    public String hello(String name) {
        return "<h1>Hello, " + name + "</h1>";
    }

    @Mapping("/")
    public Renderer index() throws Exception {
        return new TemplateRenderer("/index.htm");
    }
}

The scope of JavaBeans in IoC container can be either singleton or prototype, but make sure they are stateless, because WebWind will hold the references of these beans and treat them as singleton.

Using Guice

If you want to use Guice as IoC container, you need specify the module class in web.xml:

<init-param>
    <param-name>modules</param-name>
    <param-value>org.expressme.sample.BlogModule</param-value>
</init-param>

See Configurations to get more about configuration of Guice.

And write your module class:

public class BlogModule implements Module {
    public void configure(Binder binder) {
        binder.bind(Blog.class).asEagerSingleton();
    }
}

Using Spring

If you want to use Spring as IoC container, you need declare the beans in Spring configuration file (usually named as applicationContext.xml):

<bean class="org.expressme.sample.Blog" />

See Configurations to get more about configuration of Spring.

Need More IoC Container Support

If you want to use any other IoC container rather than Guice or Spring, you need additional work to do.

WebWind allows you to add any IoC containers (such as HiveMind, PicoContainer, etc) by writing your own ContainerFactory class. For example:

package sample;

import java.util.List;
import org.expressme.wind.container.ContainerFactory;

public class MyContainerFactory implements ContainerFactory {
    public List<Object> findAllBeans() throws ServletException {
        // TODO: return all objects managed by IoC container
    }

    public void init(Config config) throws ServletException {
        // TODO: init or find IoC container instance
    }
}

You need implement two methods above. It is easy for experienced developers. See SpringContainerFactory.java and GuiceContainerFactory.java as examples.

Specify your own container factory in web.xml with FULL CLASS NAME:

<init-param>
    <param-name>container</param-name>
    <param-value>sample.MyContainerFactory</param-value>
</init-param>