Package org.apache.velocity.tools.view

Class VelocityViewFilter

  • All Implemented Interfaces:
    javax.servlet.Filter
    public class VelocityViewFilter
extends Object
implements javax.servlet.Filter

    A filter to ensure VelocityTools Toolboxes are available in the request/session/application scopes. This can simplify the process of integration with other frameworks.

    VelocityViewFilter supports the following configuration parameters in web.xml:

    org.apache.velocity.tools
    Path and name of the toolbox configuration file. The path must be relative to the web application root directory. If this parameter is not found, the servlet will check for a toolbox file at '/WEB-INF/tools.xml'.
    org.apache.velocity.properties
    Path and name of the Velocity configuration file. The path must be relative to the web application root directory. If this parameter is not present, Velocity will check for a properties file at '/WEB-INF/velocity.properties'. If no file is found there, then Velocity is initialized with the settings in the classpath at 'org.apache.velocity.tools.view.velocity.properties'.
    org.apache.velocity.tools.loadDefaults
    By default, this is true. If set to false, then the default toolbox configuration will not be added to your (if any) custom configuration. NOTE: The default configuration will also be suppressed if you are using a deprecated toolbox.xml format and do not explicitly set this to true.
    org.apache.velocity.tools.cleanConfiguration
    By default, this is false. If set to true, then then the final toolbox configuration (the combination of any custom one(s) provided by yourself and/or the default configuration(s)) will have all invalid tools, properties, and/or data removed prior to configuring the ToolboxFactory for this servlet by a ConfigurationCleaner
    org.apache.velocity.tools.shared.config
    By default, this is true. If set to false, then the VelocityView used by this filter will not be shared with other VelocityViewFilters, VelocityViewServlets or VelocityViewTags in the application.
    org.apache.velocity.tools.context.key
    If you set a value for this property, this filter will create and prepare a ViewToolContext for each request, and then place it into the request attributes under the key you set. This is primarily for those who have this filter NOT share a config (i.e. non-shared VelocityView) and thus will find it easier to retrieve a working context from the request attributes than it would be to get the VelocityView for this filter and have it create the context for them. Most users will have no trouble getting a shared VelocityView and creating the context themselves.
    Version:
    $Id: VelocityViewFilter.java 611011 2008-01-11 01:32:59Z nbubna $

    • Constructor Detail

      • VelocityViewFilter

        public VelocityViewFilter()

    • Method Detail

      • init

        public void init​(javax.servlet.FilterConfig config)
          throws javax.servlet.ServletException

        Initializes VelocityView used to process requests. Called by the servlet container on loading.

        Specified by:
        init in interface javax.servlet.Filter
        Parameters:
        config - filter configuation
        Throws:
        javax.servlet.ServletException

      • getFilterConfig

        protected javax.servlet.FilterConfig getFilterConfig()

      • getVelocityView

        protected VelocityView getVelocityView()

      • getContextKey

        protected String getContextKey()

      • findInitParameter

        protected String findInitParameter​(String key)
        Looks up an init parameter with the specified key in either the FilterConfig or, failing that, in the ServletContext.

      • doFilter

        public void doFilter​(javax.servlet.ServletRequest request,
                     javax.servlet.ServletResponse response,
                     javax.servlet.FilterChain chain)
              throws IOException,
                     javax.servlet.ServletException
        Simply prepares the request (and/or session) toolbox(es) for other filters, servlets or whatnot to use. If a context key has been provided in the init-params of the filter or webapp, then this will also create a ViewToolContext and put it in the request attributes under that key.
        Specified by:
        doFilter in interface javax.servlet.Filter
        Throws:
        IOException
        javax.servlet.ServletException

      • createContext

        protected org.apache.velocity.context.Context createContext​(javax.servlet.http.HttpServletRequest request,
                                                            javax.servlet.http.HttpServletResponse response)

      • destroy

        public void destroy()
        Specified by:
        destroy in interface javax.servlet.Filter