Take this example of chaining view resolvers:
<bean id="viewResolver" class="org.springframework.web.servlet.view.UrlBasedViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.tiles2.TilesView"/>
</bean>
<bean id="jsonViewResolver" class="org.springframework.web.servlet.view.XmlViewResolver">
<property name="location" value="/WEB-INF/views.xml"/>
<property name="order" value="1"/>
</bean>
<property name="viewClass" value="org.springframework.web.servlet.view.tiles2.TilesView"/>
</bean>
<bean id="jsonViewResolver" class="org.springframework.web.servlet.view.XmlViewResolver">
<property name="location" value="/WEB-INF/views.xml"/>
<property name="order" value="1"/>
</bean>
And this views.xml:
<beans><bean name="jsonView" class="org.springframework.web.servlet.view.json.JsonView"/></beans>
This should evaluate each view through the XmlViewResolver, then default back to the UrlBasedViewResolver if the XmlViewResolver does not find a view.
Now, let’s say we have the following tiles definition:
<definition name="forecastOverviewReport" extends=".mainTemplate" >
<put-attribute name="pageHeader" value="Forecast Overview"/>
<put-attribute name="body" value="/WEB-INF/jsp/forecastOverviewReport.jsp"/>
</definition>
<put-attribute name="pageHeader" value="Forecast Overview"/>
<put-attribute name="body" value="/WEB-INF/jsp/forecastOverviewReport.jsp"/>
</definition>
Looks pretty good.
Now, what if we, by coincidence, have this bean definition?
<bean id="forecastOverviewReport" class="com.credera.forecasting.reporting.ForecastOverviewReport">
<property name="employeeDAO" ref="employeeDAO"/>
</bean>
<property name="employeeDAO" ref="employeeDAO"/>
</bean>
Uh oh. The XmlViewResolver will find the bean definition above (even though it’s not in the views.xml which was explicitly specified!), and give you this lovely error:
org.springframework.beans.factory.BeanNotOfRequiredTypeException: Bean named ‘forecastOverviewReport’ must be of type [org.springframework.web.servlet.View], but was actually of type [com.credera.forecasting.reporting.ForecastOverviewReport]
But without the XmlViewResolver, this would have been perfectly fine. So, if you are chaining in an XmlViewResolver, make sure none of your tiles definition names are the same as any bean definition ids.
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