A mapplet is a reusable object containing a set of transformations that you can use in multiple mappings. Use a mapplet in a mapping. Or, validate the mapplet as a rule.
Transformations in a mapplet can be reusable or non-reusable. If you add a Sequence Generator transformation to a mapplet, it must be reusable.
When you use a mapplet in a mapping, you use an instance of the mapplet. Any change made to the mapplet is inherited by all instances of the mapplet.
Mapplets can contain other mapplets. You can also use a mapplet more than once in a mapping or mapplet. You cannot have circular nesting of mapplets. For example, if mapplet A contains mapplet B, mapplet B cannot contain mapplet A.
You can create a mapplet manually. You can also generate a mapplet from a segment within a mapping or mapplet.