The value null
The value null is a reserved word, not a string. When used in place of an object belonging to an imported Java™ class, it has the same meaning as it does in the Java™ language.
Do not use null to signify an empty
string. To signify an empty string, use a pair of single quotes ('')
in the advanced macro format, or nothing at all in the basic macro
format. If you use the value null in
a string context (for example, by assigning it to a string variable),
then the macro editor or the macro runtime will
convert the value null to the string 'null'
.