code: public boolean isStale( File mergeFile )
      {
          //
          // We can write to the file if it doesn't exist yet.
          //
          if ( ! _strutsConfigFile.exists() )
          {
              return true;
          }
          
          long lastWrite = _strutsConfigFile.lastModified();
          
          if ( mergeFile != null && mergeFile.exists() && mergeFile.lastModified() > lastWrite )
          {
              return true;
          }
          
          if ( _sourceFile.lastModified() > lastWrite )
          {
              return true;
          }
          
          return false;
      }
docs: Tell whether the struts output file (struts-config-*.xml) is out of date, based on the
  file times of the source file and the (optional) struts-merge file.