The mainframe is dead, long live the mainframe.
In the 80's it was Client/Server that was going to replace and undo the Mainframe.
Well it did replace some client side usage, but the Mainframe remained THE server of choice for enterprise class systems.
BMS/MFS has seen a great drop in usage, but the mainframe as a Database, Transaction and Batch Server has if anything increased in usage.
Ironically, Client/Server has instead been replaced by the Web, with Java/C#/PHP as the languages of choice.
Instead of being replaced, the mainframe has instead incorporated the Web and Java.
Incorporated, not added, because besides the stand alone Websphere Application Server and Java running natively under z/OS Unix USS, it is built into its existing tools.
CICS is now a Web Application Server that can use both COBOL and Java as it's language of choice for Web Services and Transactions.
Java is used as a batch OO language, running under z/OS USS.
Why do this? It saves money since no software license fees are incurred that are under MVS. And if a ZIIP processor is used, MIPS cost is greatly reduced.
See
When to use? As the reporting platform for an enterprise. Secure and fast Access to databases via JDBC, as well as usage of its class libraries to produce HTML as well as PDF and EXCEL files. MVS resources, MIPS usage/cost, are freed up.
What does Rational Developer for Z have to do with this?
It incorporates all the tools for what have written about, as well as all the traditional MVS toolset into one great developers IDE for US Mainframe developers, with a great cost savings on cost of MIPS and productivity.
The mainframe developer is dead, long live the mainframe developer.
