Workflow Manual / Version 2101
Table Of ContentsWhen you are programming own expressions, respect the following general rules:
Expressions must not have any side effects.
Expressions must not hold any state.
Expressions must be repeatable any number of times.
All top level expressions used in the workflow configuration must be Boolean expressions.
Depending on their arity, expressions may have a specific number of subexpressions, which
are added through the addExpression() method. For example, a comparison has an
arity of two, as it compares exactly two expressions. A logical expression like
And or Or are n-ary, it must have at least two subexpressions, but
may have any number of expressions. In contrast to that, a Not must have
exactly one subexpression. If a maximum number of expressions is exceeded, a
WfRuntimeException
with the error code TOO_MANY_SUBEXPRESSIONS thrown.
