Overview
Data input could then be validated by the audit rules or dynamic rules. These were held on an IMS data base, so that ADF was actually written in ADF.
More complex transactions could be written by using exits coded in Cobol or PL/1. There was also a language that could be used to generate the dynamic rules on the ADF database.
By using exits in Cobol and PL/1, almost any level of complexity of IMS DC system could be developed using ADF. It had the added benefit that screens could be generated without any knowledge of MFS.
Standard ADF applications produced a series of free transactions that provided navigation from one transaction to the next via a concatenated key, and selection screens for lower segments in the hierarchy.
It was also possible to write the application almost entirely in either Cobol or PL/1 by defining it as a Special ADF application.
ADF was very popular in the 1980s in large IMS DB/DC environments as a quick development tool. Most installations used it to develop simple systems that required a low level of sophistication, and had a small budget. However some companies used it as their main tool for even the most complex on-line systems. It was at first heavily promoted by IBM, but a new version released in the mid-1980s was not purchased by many (if any) companies, mainly because it would have required some development work on existing systems to implement it. Soon after that IBM withdrew support for it, which effectively sealed its fate. See next paragraph
The correct story is by the mid-1980s IBM had two 4GL products, ADF and Cross System Product (CSP). IBM decided to phase out development of ADF in favor of CSP primarily because CSP operated on more platforms (operating systems) than ADF. IBM stopped selling ADF in April 2003 but support is still provided today for customers who still use ADF.
ADF systems were still in use during the 1990s, but as far as I know none of them made it past the end of the century as it did not support an eight digit date. Support for eight digit dates was added to ADF in January 1988 by PTF UL25256.
An obscure piece of trivia is that the load modules that were generated by ADF all started with the characters MFC. I was told that this was because it had originally been developed for a company called the Municipal Floor Company. (If this is an urban myth then I apologise for it as I would hate to mislead anyone). Actually MFC stood for Manufacturing Floor Control. ADF was created as an internal tool by IBM's Data Processing Division.
In a world where there are stamp collectors and train spotters, I am sure someone will one day write a book on the history of computer languages and if so I do hope they will consider that ADF deserves its places in history.
(written by Roy Cropper. updated by Jim Stewart)
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IMS ADF II Version 2 Release 2 is still fully supported by IBM, but has been a "mature" product since 1986. That means adaptive and corrective maintenance only, no new versions or releases.
Maintenance provided during the 2000s includes a fix to support the use of Exits and Special processing routines compiled with IBM's Enterprise PL/I compiler.
IMS ADF II v2r2 manuals are available at IBM Book Manager websites, as scanned bit maps of the 1986 manuals. Look under DB2 IMS tools
If you already pay fees for using IMS ADF II it can be evaluated as an no additional license fee cost alternative to products such as FileAid for IMS, FileAid for DB2 and similar FileManager products, in terms of providing DB2 or IMS DB ad hoc data retrieval and update access by developers and testers.
http://www.ibm.com/software/data/db2imstools/imstools-library.html#imsadf-lib
Read more about this topic: Application Development Facility