Bean session allows you to set values for which a bean has no property by getting its thing session and issuing the calls with the predicate. However, in the case that the bean does have a property mapped to the predicate, the state would not be updated. So a pair of calls like

setValue(bean, predicate, value);
setValues(bean, predicate, Collection, keepOrderFlag);

are needed.

Analogously, there should be calls like

Object getValue(bean, predicate);
Collection getValues(bean, predicate);

which will update the value of a specific property if it is mapped to the predicate.