I started learning Spring 3 and came accross SpEL.

I understand following

@Value("#{ systemProperties }")
private Properties systemProperties;
@Value("#{ systemProperties['user.region'] }")
private String userRegion;


This is used for injecting values dynamically. I understood.


But
What is use of Using the Spring Expression Language Parser?

Expression exp = PARSER.parseExpression("'foo'");
String value = exp.getValue(String.class);


I could not understand use of above. How am I going to use it? Is it only something like assert? Used for testing?