Class AgentDecoratorMapper

  • All Implemented Interfaces:
    DecoratorMapper

    public final class AgentDecoratorMapper
    extends AbstractDecoratorMapper
    The AgentDecoratorMapper can determine the user-agent (i.e. web-browser) requesting a page, and map to a suitable Decorator.

    This can be useful for supplying different versions of the same content for different browsers (e.g. vanilla HTML for Lynx, complex tables and frames for Netscape, extra stuff for IE5, etc).

    This can also be used to enhance search-engine ratings by using a 'bait and switch' system - this involves showing a search-engine friendly of the content to spiders only.

    When AgentDecoratorMapper is in the chain, it will request the appropriate Decorator from its parent. It will then add an extention to the filename of the Decorator, and if that file exists it shall be used as the Decorator instead. For example, if the Decorator path is /blah.jsp and the detected user-agent is ie, the path /blah-ie.jsp shall be used.

    The agent mappings are configured by passing properties with match. as a prefix. For example: 'match.MSIE'=ie , 'match.Lynx'=plain .

    Version:
    $Revision: 1.2 $
    Author:
    Joe Walnes
    See Also:
    DecoratorMapper
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      Decorator getDecorator​(javax.servlet.http.HttpServletRequest request, Page page)
      Delegate to parent.
      private java.lang.String getExt​(java.lang.String userAgent)
      Get extention for user-agent.
      void init​(Config config, java.util.Properties properties, DecoratorMapper parent)
      Set parent.
      private void initMap​(java.util.Properties props)
      Initialize user-agent mappings.
      private static java.lang.String modifyPath​(java.lang.String path, java.lang.String ext)
      Change /abc/def.jsp into /abc/def-XYZ.jsp
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • map

        private java.util.Map map
    • Constructor Detail

      • AgentDecoratorMapper

        public AgentDecoratorMapper()
    • Method Detail

      • init

        public void init​(Config config,
                         java.util.Properties properties,
                         DecoratorMapper parent)
                  throws java.lang.InstantiationException
        Description copied from class: AbstractDecoratorMapper
        Set parent.
        Specified by:
        init in interface DecoratorMapper
        Overrides:
        init in class AbstractDecoratorMapper
        Parameters:
        config - Config supplied by Servlet or Filter.
        properties - Any initialization properties (specific to implementation).
        Throws:
        java.lang.InstantiationException - should be thrown if the implementation cannot be initialized properly.
      • getExt

        private java.lang.String getExt​(java.lang.String userAgent)
        Get extention for user-agent.
      • modifyPath

        private static java.lang.String modifyPath​(java.lang.String path,
                                                   java.lang.String ext)
        Change /abc/def.jsp into /abc/def-XYZ.jsp
      • initMap

        private void initMap​(java.util.Properties props)
        Initialize user-agent mappings.