when read the acgi.xml and according source code,I found the way spring read the value ,on the other hand,how spring choose the editor to resolve the value.
for example,the "filterInvocationDefinitionSource" properties,Spring will choose the class "FilterInvocationDefinitionSourceEditor" to solve  the "filterInvocationDefinitionSource".u may notes that
the "FilterInvocationDefinitionSourceEditor" = "filterInvocationDefinitionSource" plus "editor" ignore the case.
That is exactly what Spring do.

in acegi , "filterInvocationDefinitionSource"  use to store urls for filering,so when u understand the its struture ,u can
get the url for database,not explicitly.

for the key word " CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON",it means u must
set the properties name lower case,otherwise will be error.

and "  PATTERN_TYPE_APACHE_ANT" means use class PathBasedFilterInvocationDefinitionMap,default use
class RegExpBasedFilterInvocationDefinitionMap.