16.3 Tiles

It is possible to integrate Tiles - just as any other view technology - in web applications using Spring. The following describes in a broad way how to do this.

NOTE: This section focuses on Spring's support for Tiles 2 (the standalone version of Tiles, requiring Java 5+) in the org.springframework.web.servlet.view.tiles2 package. Spring also continues to support Tiles 1.x (a.k.a. "Struts Tiles", as shipped with Struts 1.1+; compatible with Java 1.4) in the original org.springframework.web.servlet.view.tiles package.

16.3.1 Dependencies

To be able to use Tiles you have to have a couple of additional dependencies included in your project. The following is the list of dependencies you need.

  • Tiles version 2.0.4 or higher

  • Commons BeanUtils

  • Commons Digester

  • Commons Logging

These dependencies are all available in the Spring distribution.

16.3.2 How to integrate Tiles

To be able to use Tiles, you have to configure it using files containing definitions (for basic information on definitions and other Tiles concepts, please have a look at http://tiles.apache.org). In Spring this is done using the TilesConfigurer. Have a look at the following piece of example ApplicationContext configuration:

<bean id="tilesConfigurer" class="org.springframework.web.servlet.view.tiles2.TilesConfigurer">
  <property name="definitions">
    <list>
      <value>/WEB-INF/defs/general.xml</value>
      <value>/WEB-INF/defs/widgets.xml</value>
      <value>/WEB-INF/defs/administrator.xml</value>
      <value>/WEB-INF/defs/customer.xml</value>
      <value>/WEB-INF/defs/templates.xml</value>
    </list>
  </property>
</bean>

As you can see, there are five files containing definitions, which are all located in the 'WEB-INF/defs' directory. At initialization of the WebApplicationContext, the files will be loaded and the definitions factory will be initialized. After that has been done, the Tiles includes in the definition files can be used as views within your Spring web application. To be able to use the views you have to have a ViewResolver just as with any other view technology used with Spring. Below you can find two possibilities, the UrlBasedViewResolver and the ResourceBundleViewResolver.

16.3.2.1  UrlBasedViewResolver

The UrlBasedViewResolver instantiates the given viewClass for each view it has to resolve.

<bean id="viewResolver" class="org.springframework.web.servlet.view.UrlBasedViewResolver">
  <property name="viewClass" value="org.springframework.web.servlet.view.tiles2.TilesView"/>
</bean>

16.3.2.2  ResourceBundleViewResolver

The ResourceBundleViewResolver has to be provided with a property file containing viewnames and viewclasses the resolver can use:

<bean id="viewResolver" class="org.springframework.web.servlet.view.ResourceBundleViewResolver">
  <property name="basename" value="views"/>
</bean>
...
welcomeView.class=org.springframework.web.servlet.view.tiles2.TilesView
welcomeView.url=welcome (this is the name of a Tiles definition)

vetsView.class=org.springframework.web.servlet.view.tiles2.TilesView
vetsView.url=vetsView (again, this is the name of a Tiles definition)

findOwnersForm.class=org.springframework.web.servlet.view.JstlView
findOwnersForm.url=/WEB-INF/jsp/findOwners.jsp
...

As you can see, when using the ResourceBundleViewResolver, you can easily mix different view technologies.

Note that the TilesView class for Tiles 2 supports JSTL (the JSP Standard Tag Library) out of the box, whereas there is a separate TilesJstlView subclass in the Tiles 1.x support.

16.3.2.3 SimpleSpringPreparerFactory and SpringBeanPreparerFactory

As an advanced feature, Spring also supports two special Tiles 2 PreparerFactory implementations. Check out the Tiles documentation for details on how to use ViewPreparer references in your Tiles definition files.

Specify SimpleSpringPreparerFactory to autowire ViewPreparer instances based on specified preparer classes, applying Spring's container callbacks as well as applying configured Spring BeanPostProcessors. If Spring's context-wide annotation-config has been activated, annotations in ViewPreparer classes will be automatically detected and applied. Note that this expects preparer classes in the Tiles definition files, just like the default PreparerFactory does.

Specify SpringBeanPreparerFactory to operate on specified preparer names instead of classes, obtaining the corresponding Spring bean from the DispatcherServlet's application context. The full bean creation process will be in the control of the Spring application context in this case, allowing for the use of explicit dependency injection configuration, scoped beans etc. Note that you need to define one Spring bean definition per preparer name (as used in your Tiles definitions).

<bean id="tilesConfigurer" class="org.springframework.web.servlet.view.tiles2.TilesConfigurer">
  <property name="definitions">
    <list>
      <value>/WEB-INF/defs/general.xml</value>
      <value>/WEB-INF/defs/widgets.xml</value>
      <value>/WEB-INF/defs/administrator.xml</value>
      <value>/WEB-INF/defs/customer.xml</value>
      <value>/WEB-INF/defs/templates.xml</value>
    </list>
  </property>

  <!-- resolving preparer names as Spring bean definition names -->
  <property name="preparerFactoryClass"
       value="org.springframework.web.servlet.view.tiles2.SpringBeanPreparerFactory"/>

</bean>