Vaadin-Spring Integration

I remember the time when i was trying to integrate Spring with Struts2 and GWT applications. The problem was rather documenting the integration stuff i tried to remember them and as usual tend to forgot them. So this time have decided to document the Spring integration with Vaadin.

• web.xml changes

So first we need to add the Spring Context listener to load the bean configuration file.

<listener>

  <listener-class>

    org.springframework.web.context.ContextLoaderListener

  </listener-class>

</listener>

<context-param>

  <param-name>contextConfigLocation</param-name>

  <param-value>/WEB-INF/applicationContext.xml</param-value>

</context-param>

Add the Spring Servlet to intercept Vaadin requests

<servlet>

  <servlet-name>VaadinSpringServlet</servlet-name>

  <servlet-class>com.dhaval.web.vaadin.spring.servlet.SpringApplicationServlet</servlet-class>

  <init-param>

    <param-name>applicationBean</param-name>

    <param-value>testApplication</param-value>

  </init-param>

</servlet>

<servlet-mapping>

  <servlet-name>VaadinSpringServlet</servlet-name>

  <url-pattern>/vaadin/*</url-pattern>

</context-param>

• Spring Servlet

This servlet connects the Spring with Vaadin. The servlet loads the Vaadin Application class and dispatches all the HTTP requests/responses. The Servlet is available in the Simple Application provided by Vaadin Team for Spring integration.

• Spring bean configuration

<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">

  <property>name="driverClassName" value="${db.driver}"/>

  <property>name="url" value="${db.url}"/>

  <property>name="username" value="${db.user}"/>

  <property>name="password" value="${db.pass}"/>    

</bean>

<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">

  <property>name="dataSource" ref="dataSource"/>

</bean>

<bean id="dao.user" class="com.dhaval.web.vaadin.spring.dao.UserDaoImpl">

  <constructor-arg>ref="jdbcTemplate"/>

</bean>

<bean id="testApplication" class="com.dhaval.web.vaadin.spring.MyApplication">

  <constructor-arg>ref="dao.user"/>

</bean>

testApplication bean id is same as we have given in the web.xml as an init-param to Spring Servlet.

• Vaadin Main Application class

This is my Vaadin Application class

public class MyApplication extends Application{

    private UserDaoImpl userDao;

    public MyApplication(UserDaoImpl userDao){

        this.userDao = userDao;

    }

    public void init() {

        Window mainWindow = new Window("Simple Vaadin Spring Integration");

        final TextField txtUser = new TextField("Enter username");

        Button btnCheckUser = new Button("Check Username");

        final Label lblCheckMsg = new Label("");

        btnCheckUser.addListener(new Button.ClickListener() {

            public void buttonClick(ClickEvent event) {

                boolean result = userDao.hasUser(txtUser.getValue().toString());

                if(result){

                    lblCheckMsg.setValue("Available");

                }else{

                    lblCheckMsg.setValue("Not Available");

                }

            }

        });

        mainWindow.addComponent(txtUser);

        mainWindow.addComponent(btnCheckUser);

        mainWindow.addComponent(lblCheckMsg);

        setMainWindow(mainWindow);

   }

}

The full source code is available at vaadin-spring-integration in download section.