Using Velocity Tools with Spring 3.0.3

问题:

When I update the bean:

<bean id="viewResolver" class="org.springframework.web.servlet.view.velocity.VelocityViewResolver">
  <property name="cache" value="true"/>
  <property name="prefix" value=""/>
  <property name="suffix" value=".vm"/>
  <property name="toolboxConfigLocation" value="tools.xml" />
</bean>

With the tools.xml path for Velocity Tools, I get:

Caused by: 
java.lang.ClassNotFoundException: org.apache.velocity.tools.view.ToolboxManager

I've tried plugging in tools version 2 and 1.4, neither have this package structure. Did I miss something obvious? What version of Velocity Tools is the Spring/Velocity component supporting?

回答1:

Spring has very outdated Velocity support by default. I extend VelocityView class from Spring and override createVelocityContext method where I initialize Tools myself. Here is how it looks at the end.

回答2:

I use a little bit simpler of a way. I also cannot force Velocity Tools to work due to lack of configuration documentation and examples. I just get the velocity-generic-tools-2.0.jar and make a little change in my view resolver:

<bean id="velocityViewResolver" 
    class="org.springframework.web.servlet.view.velocity.VelocityViewResolver">
    <property name="order" value="1"/>
    <property name="prefix" value="/WEB-INF/vm/"/>
    <property name="suffix" value=".vm"/>

    <property name="exposeSpringMacroHelpers" value="true"/>
    <property name="contentType" value="text/html;charset=UTF-8"/>
    <property name="attributesMap">
        <map>
            <!--Velocity Escape Tool-->
            <entry key="esc"><bean class="org.apache.velocity.tools.generic.EscapeTool"/></entry>
        </map>
    </property>        
</bean>

Then, in the velocity template you can use it as usual $esc.html($htmlCodeVar). This solution is very simple, without tons of configs and overriding spring classes.

回答3:

With 3.0.5 I used a similar class to what serg posted, with the only modification being to use the updated classes which spring did not use (tail through VelocityToolboxView -> ServletToolboxManager (used in the createVelocityContext we have overridden) That is the class which is deprecated, so I modified the initVelocityToolContext in serg's answer to be:

private ToolContext getToolContext() throws IllegalStateException, IOException {
  if (toolContext == null) {
    XmlFactoryConfiguration factoryConfiguration = new XmlFactoryConfiguration("Default Tools");
    factoryConfiguration.read(getServletContext().getResourceAsStream(getToolboxConfigLocation()));
    ToolboxFactory factory = factoryConfiguration.createFactory();
    factory.configure(factoryConfiguration);
    toolContext = new ToolContext();
    for (String scope : Scope.values()) {
      toolContext.addToolbox(factory.createToolbox(scope));
    }
  }
  return toolContext;
}

I also had to change the line which created the VelocityContext to call this method obviously.

My bean now looks like:

<bean id="viewResolver" class="org.springframework.web.servlet.view.velocity.VelocityLayoutViewResolver"
      p:cache="false"
      p:prefix=""
      p:suffix=".vm"
      p:layoutUrl="templates/main.vm"
      p:toolboxConfigLocation="/WEB-INF/velocity/velocity-toolbox.xml"
      p:viewClass="path.to.overriden.class.VelocityToolsLayoutView"
/>

回答4:

Inspired by answers from Scott and serg, here's another way to do it that does not require XML: http://squirrel.pl/blog/2012/07/13/spring-velocity-tools-no-xml/

public class MyVelocityToolboxView extends VelocityView {
    @Override
    protected Context createVelocityContext(Map<String, Object> model,
            HttpServletRequest request, HttpServletResponse response) {
        ViewToolContext context = new ViewToolContext(getVelocityEngine(),
                request, response, getServletContext());

        ToolboxFactory factory = new ToolboxFactory();
        factory.configure(ConfigurationUtils.getVelocityView());

        for (String scope : Scope.values()) {
            context.addToolbox(factory.createToolbox(scope));
        }

        if (model != null) {
            for (Map.Entry<String, Object> entry : (Set<Map.Entry<String, Object>>) model
                    .entrySet()) {
                context.put(entry.getKey(), entry.getValue());
            }
        }
        return context;
    }
}

回答5:

Inspired by all the answers above, this is my implementation of VelocityLayoutView for spring and velocity-tools 2.0, added some improvement!

public class VelocityToolsView extends VelocityLayoutView {

    private static final String TOOL_MANAGER_KEY = ViewToolManager.class.getName();

    @Override
    protected Context createVelocityContext(
            Map<String, Object> model, HttpServletRequest request, HttpServletResponse response) {
        ServletContext application = getServletContext();

        // use a shared instance of ViewToolManager
        ViewToolManager toolManager = (ViewToolManager)application.getAttribute(TOOL_MANAGER_KEY);
        if(toolManager == null) {
            toolManager = createToolManager(getVelocityEngine(), getToolboxConfigLocation(), application);
            application.setAttribute(TOOL_MANAGER_KEY, toolManager);
        }

        ViewToolContext toolContext = toolManager.createContext(request, response);
        if(model != null) { toolContext.putAll(model); }

        return toolContext;
    }

    private ViewToolManager createToolManager(VelocityEngine velocity, String toolFile, ServletContext application) {
        ViewToolManager toolManager = new ViewToolManager(application, false, false);
        toolManager.setVelocityEngine(velocity);

        // generic & view tools config
        FactoryConfiguration config = ConfigurationUtils.getVelocityView();
        // user defined tools config
        if(toolFile != null) {
            FactoryConfiguration userConfig = ConfigurationUtils.load(application.getRealPath(toolFile));
            config.addConfiguration(userConfig);
        }
        toolManager.configure(config);

        return toolManager;
    }
}

回答6:

I found that this variation on @serg's technique worked for me.