I am testing this code in weblogic 12C which is ofcourse servlet 3.0/EL2.2 compatible.
But the above code throws the error :
Error: Function colorBlender is not declared in the tag library associated with http://xmlns.oracle.com/dss/adf/faces. Declare the function in the corresponding tag library descriptor or use the prefix associated with the tag library that declares this function.
Why does ADF expect the custom function colorBlender() to be in "http://xmlns.oracle.com/dss/adf/faces" namespace?