Jackson Structured Programming

Jackson structured programming (JSP) or Jackson program design methodology is a method developed by Michael A. Jackson in 1970s for program design and modeling. This method is based on the fact that the program's structure depends on the structure of data, which need to be processed, so the data's structure can be used to form the program's structure. The JSP method and principles of program design outlined by A. Jackson in a same-named document can be used to design the programs of any complexity, direction and with the use of any preferred programming language, which has structured control constructs (C, Java, Perl). Moreover, the program's design using JSP is one of the simplest structured programming techniques because it focuses on the existing flows of inputs and outputs letting one make the decomposition and so resulting JSP diagram can be read top-down or bottom-up.

The JSP method is the most effective in a case of high degree of data structuring and is applied to the processing the data structure or the data flow, which can be described in a form of the hierarchical structure of sequential, optional and iterated elements. The Jackson structured programming method is used in development a detailed program management structure and is based on the possibility of presenting the data structures and programs structures by the single set of basic constructions, in connection with which were proposed and currently are successfully used four basic data structures: simple operation, sequence of operations, iteration, and selection.

The Jackson Structured Programming (JSP) Diagram solution extends the functionality and drawing abilities of the ConceptDraw DIAGRAM software with large variety of predesigned vector objects of actions, processes, procedures, selection, iteration, arrows and connectors to join the objects in a required way during the Jackson structured development and designing Jackson structured programming diagrams, JSP diagram, Jackson structure diagram (JSD), Program structure diagram. Moreover, it includes the set of illustrative samples and examples of JSP diagrams reflecting solution’s abilities. The powerful abilities of this solution make the ConceptDraw DIAGRAM ideal assistant for programmers, software developers, structural programmers, computer engineers, applications constructors, designers, specialists in structured programming and Jackson systems design, and other technical, computer and software specialists. 

Examples

There are a few samples that you see on this page which were created in the ConceptDraw DIAGRAM application by using the Jackson Structured Programming (JSP) Diagrams solution. Some of the solution's capabilities as well as the professional results which you can achieve are all demonstrated here on this page.

All source documents are vector graphic documents which are always available for modifying, reviewing and/or converting to many different formats, such as MS PowerPoint, PDF file, MS Visio, and many other graphic ones from the ConceptDraw Solution Park or ConceptDraw STORE. The Jackson Structured Programming (JSP) Diagrams solution is available to all ConceptDraw DIAGRAM users to get installed and used while working in the ConceptDraw DIAGRAM diagramming and drawing software.

Example 1: Jackson Diagram

This diagram was created in ConceptDraw DIAGRAM using the Jackson Structured Programming (JSP) Diagram library from the Jackson Structured Programming (JSP) Diagram Solution. An experienced user spent 10 minutes creating this sample.

This Jackson structured programming (JSP) sample was drawn on the base of the Wikimedia Commons file and demonstrates two diagrams at once: Data diagram and Process diagram. The main goal of Jackson structured programming is a development of easily modified programs, at this, the minor tweaks in existing structures lead to the minor changes in inputs and outputs of programs constructed using the JSP. Typically, the Jackson structured programming supposes the execution of several sequential steps, such as drawing of JSD for inputs and outputs, merging into the JSD program, making the list of operations and allocating them, converting the sequence of blocks to text, and adding conditions for selection and iteration. Now, the construction of clear and compact JSDs isn't a complex process due to the special ready-made vector objects corresponding to JSP notation and offered by the Jackson Structured Programming (JSP) Diagram library from the Jackson Structured Programming (JSP) Diagram solution.

Jackson Structured Programming is as follows:

"Jackson Structured Programming or JSP is a method for structured programming based on correspondences between data stream structure and program structure. The method is closely related in concept to creating a parser for a regular expression that describes the data stream structure, but tries to build a program structure that matches more than one data stream and provides guidance and techniques to compensate the limited lookahead and the clashes between the structures of the different data streams.

JSP was originally developed in the 1970s by IT consultant Michael A. Jackson and documented in his 1975 book Principles of Program Design. Jackson's aim was to improve the general standard of COBOL programming, but the method is still useful when coding with modern programming languages such as C and Perl. And while JSP was originally geared towards writing batch-style file processing programs, its principles are still useful when programming in the small, below the level where object-oriented methods become important.

Jackson Structured Programming was seen by many as related to Warnier Structured Programming, but the latter method focused almost exclusively on the structure of the output stream.

As a method of programming, JSP is more straightfoward than other structured methods, avoiding the leaps of intuition needed to successfully program using, say, top-down decomposition. And although it imposes a structure upon a program which improves its modifiability and maintainability, the structure is rather different from the type of structure advocated by Wirth, Dijkstra, et al."

JSP structures programs in terms of four component types:

• fundamental operations
• sequences
• iterations
• selections

In addition there are a number of constructs to support backtracking and to capture beneficient and intolerable side-effects.

Jackson Structured Programming was supported by the PDF and JSP Tool programs, but now benefits from greatly enhanced support within the JSP Structure Editor component of the KCSL Jackson Workbench.