shibboleth.Functions.Constant constructs a Function that returns its input argument. It adapts a fixed configuration value into a Function object.
shibboleth.BiFunctions.Constant 4.1 constructs a BiFunction that returns its input argument. It adapts a fixed configuration value into a BiFunction object.
They are abstract beans so require a single constructor argument, which will always be returned when the function is called.
Because of Spring's byzantine type conversion behavior, it's usually best to supply a bean of a specific type as an argument to ensure that the function returns exactly what's intended.
Example
<bean parent="shibboleth.Functions.Constant"> <constructor-arg> <!-- Fully define the bean to return from the function here. --> <bean class="...." /> </constructor-arg> </bean>