It's fairly easy to define your own custom search expression. You create a class implementing a certain interface und call it just like the search expression. That's it!
BootsFaces uses a convention over configuration approach to define search expressions. The class
implementing the search expression must be in the package net.bootsfaces.expressions.
The name of the class is the name of the search expression, plus the suffix ExpressionResolver.
As usual, the first letter of the class has to be upper case.
For example, to implement a search expression giving you the parent element of the current element
in the JSF tree, use this code to implement @parent:
Of course, @parent is already a BootsFaces search expression,
but you get the idea.