A.13. web.xml

The web.xml file is a standard descriptor of a Java EE web application and should be created for the Middleware, Web Client and Web Portal blocks.

In an application project, web.xml files are located in the web/WEB-INF folders of the corresponding modules.

web.xml for the Middleware block (core project module) has the following content:

<web-app xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
         version="3.0">

  <!-- Application properties config files -->
  <context-param>
      <param-name>appPropertiesConfig</param-name>
      <param-value>
          classpath:cuba-app.properties
          classpath:app.properties
          file:${catalina.home}/conf/app-core/local.app.properties
      </param-value>
  </context-param>

  <listener>
      <listener-class>com.haulmont.cuba.core.sys.AppContextLoader</listener-class>
  </listener>

  <servlet>
      <servlet-name>remoting</servlet-name>
      <servlet-class>com.haulmont.cuba.core.sys.remoting.RemotingServlet</servlet-class>
      <load-on-startup>1</load-on-startup>
  </servlet>

  <servlet-mapping>
      <servlet-name>remoting</servlet-name>
      <url-pattern>/remoting/*</url-pattern>
  </servlet-mapping>

  <servlet>
      <servlet-name>restapi</servlet-name>
      <servlet-class>com.haulmont.cuba.core.sys.restapi.RestApiServlet</servlet-class>
      <load-on-startup>1</load-on-startup>
  </servlet>

  <servlet-mapping>
      <servlet-name>restapi</servlet-name>
      <url-pattern>/api/*</url-pattern>
  </servlet-mapping>
</web-app>

The context-param elements define initializing parameters for the ServletContext object of the current web application. The list of application property files is also defined in the appPropertiesConfig parameter.

The listener element defines a listener class implementing the ServletContextListener interface. The Middleware block uses the AppContextLoader class as a listener. This class initializes the AppContext.

Servlet descriptions follow, including the RemotingServlet class, mandatory for the Middleware block. This servlet is accessible via the /remoting/* URL, and is related to the remote access container (see remoting-spring.xml).

web.xml for the Web Client block (web project module) has the following content:

<web-app xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
         version="3.0">

  <context-param>
      <description>Vaadin production mode</description>
      <param-name>productionMode</param-name>
      <param-value>false</param-value>
  </context-param>

  <context-param>
      <param-name>appPropertiesConfig</param-name>
      <param-value>
          classpath:cuba-web-app.properties
          classpath:web-app.properties
          file:${catalina.home}/conf/app/local.app.properties
      </param-value>
  </context-param>

  <listener>
      <listener-class>com.vaadin.server.communication.JSR356WebsocketInitializer</listener-class>
  </listener>
  <listener>
      <listener-class>com.haulmont.cuba.web.sys.WebAppContextLoader</listener-class>
  </listener>

  <servlet>
      <servlet-name>app_servlet</servlet-name>
      <servlet-class>com.haulmont.cuba.web.sys.CubaApplicationServlet</servlet-class>
      <init-param>
          <param-name>application</param-name>
          <param-value>com.haulmont.sales.web.App</param-value>
      </init-param>
      <init-param>
          <param-name>widgetset</param-name>
          <param-value>com.haulmont.cuba.web.toolkit.ui.WidgetSet</param-value>
      </init-param>
      <init-param>
          <param-name>UI</param-name>
          <param-value>com.haulmont.cuba.web.AppUI</param-value>
      </init-param>
      <init-param>
          <param-name>UIProvider</param-name>
          <param-value>com.haulmont.cuba.web.sys.CubaUIProvider</param-value>
      </init-param>
      <async-supported>true</async-supported>
  </servlet>

  <servlet-mapping>
      <servlet-name>app_servlet</servlet-name>
      <url-pattern>/*</url-pattern>
  </servlet-mapping>

  <filter>
      <filter-name>cuba_filter</filter-name>
      <filter-class>com.haulmont.cuba.web.sys.CubaHttpFilter</filter-class>
      <async-supported>true</async-supported>
  </filter>

  <filter-mapping>
      <filter-name>cuba_filter</filter-name>
      <url-pattern>/*</url-pattern>
  </filter-mapping>

</web-app>

The list of application property files is defined in the appPropertiesConfig parameter. The productionMode property disables the Vaadin framework debugging mode.

The Web Client block uses the WebAppContextLoader class as a ServletContextListener.

Next, the CubaApplicationServlet is defined, providing the generic user interface implementation based on the Vaadin framework. The servlet has a number of parameters, including:

  • application – defines a project specific client application class, inherited from com.haulmont.cuba.web.App.

  • widgetset – defines a set of GWT components used on the browser side.

Later, the CubaHttpFilter required for functioning of the Web Client block is defined.