anchor.diff:  (the developer) should make to the `Messenger.groovy` source file when the
   execution of the program is paused:
   
  -[source,java,indent=0]
  +[source,groovy,indent=0]
   [subs="verbatim,quotes"]
   ----
   	package org.springframework.scripting
  
positive.code: The following example shows an `org.springframework.web.servlet.mvc.Controller` implemented
  by using the Groovy dynamic language:
  
  [source,java,indent=0]
  [subs="verbatim,quotes"]
  ----
  	// from the file '/WEB-INF/groovy/FortuneController.groovy'
  
negative.code: does not work:
  
  .An approach that cannot work
  [source,groovy,indent=0]
  [subs="verbatim,quotes"]
  ----
  	// from the file 'Messenger.groovy'
  