JSP trimSpaces directive not working!

I'm trying to trim JSP whitespace using the trimSpaces directive in my web.xml, but it's not working. Here's my web.xml:

<?xml version="1.0" encoding="UTF-8"?>
<web-app    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
            xmlns="http://java.sun.com/xml/ns/javaee" 
            xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_4.xsd" 
            xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" 
            id="WebApp_ID" 
            version="2.4">

  <display-name>MyWebApp</display-name>

  <servlet>
    <servlet-name>MyServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-o开发者_如何学编程n-startup>1</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>MyServlet</servlet-name>
    <url-pattern>/login</url-pattern>
  </servlet-mapping>

  <init-param>
    <param-name>trimSpaces</param-name>
    <param-value>true</param-value>
  </init-param>

</web-app>

I'm new at this and not sure how to go about debugging the problem. I tried putting the <init-param> inside the <servlet> tags, but that didn't work. Maybe there's something wrong with the xml schema? Or maybe my JSP version isn't correct? (I only installed Tomcat a few months ago, so it's pretty recent)

I'm using Tomcat 7. Also using Spring, as you can see.

Any suggestions?

---

The <init-param> for the JspServlet needs to go in the web.xml of the servletcontainer itself, not of your webapp. Go to the Tomcat installation folder and open the /conf/web.xml file. Locate the <servlet> entry of the JspServlet and add the <init-param> there.

If you'd like to configure it globally in the web.xml of your webapp, for example because the servletcontainer configuration is outside your control, then you need to set the <trim-directive-whitespaces> property of the <jsp-config> instead.

<jsp-config>
    <jsp-property-group>
        <url-pattern>*.jsp</url-pattern>
        <trim-directive-whitespaces>true</trim-directive-whitespaces>
     </jsp-property-group>
</jsp-config>

---

I added the trimSpaces directive to the web.xml in my tomcat/conf directory and found that it was ignored when I restarted my server. However, out of curiosity I also added a scratchdir directive to override the default work directory, just to see if this option was also ignored. When I restarted tomcat after adding this param, both the scratchdir and trimSpace directives were picked up and applied. I don't really understand why adding the trimSpace directive on its own takes not effect yet adding it in conjunction with another directive causes it to work? It's a bit of a clunky solution but at least it works. I'm using tomcat 6.0.33.

<servlet>
    <servlet-name>jsp</servlet-name>
    <servlet-class>org.apache.jasper.servlet.JspServlet</servlet-class>
    <!-- trim white space in jsp -->
    <init-param>
        <param-name>trimSpaces</param-name>
        <param-value>true</param-value>
    </init-param>
    <init-param>
        <param-name>scratchdir</param-name>
        <param-value>/temp/tomcat/work</param-value>
    </init-param>
    <!-- these params are here by default -->
    <init-param>
        <param-name>fork</param-name>
        <param-value>false</param-value>
    </init-param>
    <init-param>
        <param-name>xpoweredBy</param-name>
        <param-value>false</param-value>
    </init-param>
    <load-on-startup>3</load-on-startup>
</servlet>