This project implements a RESTful Webservice using Jersey and Guice.

Jersey is a very popular Java toolkit that abstracts away the low level details of the client-server communication, while Guice is one of the most popular dependency injection frameworks.

Jersey uses its own depencency injection framework HK2. There is a bridge between Jersey and Guice, but it is not easy to elegantly configure REST endpoints that use Guice dependency injection. This is where this project comes in. It defines a RestServletModule, that allows you to configure your REST application in the same way as all the other parts within it. This RestServletModule adds a rest() and a packages() function to configure Jersey2. This pays off by giving us a clear and elegant application structure. A typical configuration would be:

public class MyServletContextListener extends GuiceServletContextListener {
    @Override
    protected Injector getInjector() {
        return Guice.createInjector(new RestServletModule() {
            @Override
            protected void configureServlets() {
                bind(WelcomeTexter.class);
                bind(HelloWorldServlet.class).in(Scopes.SINGLETON);
                serve("/hello").with(HelloWorldServlet.class);
                
                rest("/app/*").packages("com.example.jerseyguice.app");
                
                bind(User.class);
                bind(UserDao.class).to(InMemoryUserDao.class);
                bind(InMemoryUserDatabase.class);
            }
        });
    }
}

The solution is made for the google app engine but it should work on any application server.

For details see my blog about RESTful Webservices with Jersey 2 and Guice. For more information about the design principles behind it see my other blogs.

The source code for the tutorials can be found in the tutorials subfolder.