Skeleton (computer programming)

Skeleton programming is a style of computer programming based on simple high-level program structures and so called dummy code. Program skeletons resemble pseudocode, but allow parsing, compilation and testing of the code. Dummy code is inserted in a program skeleton to simulate processing and avoid compilation error messages. It may involve empty function declarations, or functions that return a correct result only for a simple test case where the expected response of the code is known. Skeleton programming facilitates a top-down design approach, where a partially functional system with complete high-level structures is designed and coded, and this system is then progressively expanded to fulfill the requirements of the project. Program skeletons are also sometimes used for high-level descriptions of algorithms. A program skeleton may also be utilized as a template that reflects syntax and structures commonly used in a wide class of problems. Skeleton programs are utilized in the template method design pattern used in object-oriented programming. In object-oriented programming, dummy code corresponds to an abstract method, a method stub or a mock object. In the Java remote method invocation (Java RMI) nomenclature, a stub communicates on the client-side with a skeleton on the server-side. A class skeleton is an outline of a class that is used in software engineering. It contains a description of the class's roles, and describes the purposes of the variables and methods, but does not implement them. The class is later implemented from the skeleton. The skeleton can also be known as either an interface or an abstract class, with languages that follow a polymorphic paradigm.