title: Legacy Wrapping author: Paul Asman email address: paul.asman@ny.frb.org postal address: Federal Reserve Bank of New York, New York, NY 10045 phone: 212-720-6637 abstract: "Legacy Wrapping" contains four patterns. The core pattern, "To Wrap or Not to Wrap," provides tests to determine whether a given legacy application has the requisite qualities necessary for successful wrapping. The second, "Respect for Wrappers," deals with reluctance to wrap legacy applications, and offers ways of mitigating this reluctance. It finds parallels between legacy wrapping and object reuse, and sees legacy wrapping as sharing virtues of pattern use. The other two patterns are more narrowly focused. "Single Wrappers and Multiple Wrappers" discusses whether one or many wrappers should be used to wrap a suitable application, and finds the answer in basic OO principles rather than in anything peculiar to wrapping. "Wrapping, Not Adapting," on the other hand, shows that some techniques developed for use solely within an object framework do not fit legacy wrapping, where objects access applications outside that framework. ftp directory: asman