ExpressionFunction

The bean named shibboleth.Functions.Expression executes a Spring Expression Language (SpEL) expression to implement an arbitrary Function signature.

The bean named shibboleth.BiFunctions.Expression ^4.1executes a Spring Expression Language (SpEL) expression to implement an arbitrary BiFunction signature.

An Expression Function is instantiated by supplying a string argument that contains a SpEL expression to evaluate.

Example

<bean id="MyFunction" parent="shibboleth.Functions.Expression"
	c:expression="#input + 42" />

Reference

The following additional bean properties are available:

PropertyName	Type	Default	Description

PropertyName	Type	Default	Description
customObject	Bean/Reference		An object to make available to the script via a variable named `custom`
returnOnError	Object	null	What to return if the expression fails
hideExceptions	boolean	false	If true, then the `returnOnError` value is returned if the expression raises an exception, otherwise the exception is passed out
inputType (Function variant)	Class<?>		Adds type checking against the input to the function to enforce type safety
inputTypes (BiFunction variant)	Pair<Class<?>,Class<?>>		Adds type checking against the input to the function to enforce type safety
outputType	Class<?>		Adds type checking against the output of the function to enforce type safety

For the Function variant, the expression environment will have these variables populated:

input - the function input
custom - the object set via the customObject property, if any

For the BiFunction variant, the expression environment will have these variables populated:

input1 - the first function input
input2 - the second function input
custom - the object set via the customObject property, if any