William van den Heuvel

Java

Since 2001 I have experience with Java. I turned my focus on distributed client/server systems involving Java clients connecting to the IBM mainframe server. I have practical experience designing and developing Web applications using Enterprise Java (JSP, Servlet, EJB) and TCP gateways on the IBM mainframe. Following is a brief resume of my experience with Java.

The resume is in reverse chronological order.

2002-2004	My last big project on the IBM mainframe (2002) was a connector that involved writing a Java EJB on the client side, and a concurrent TCP server on the mainframe side. The communication was done using native TCP/IP sockets and the request/response messages were wrapped in XML. I wrote the XML parser/generator on the IBM mainframe and used an existing XML parser in the EJB. This project also involved writing Servlets, and the HTML and Javascript on the web browser.
2001-2002 Winterthur Versicherungen (Winterthur,CH)	In 2001, I started taking interest in client/Server systems. I had written a stand-alone Java application using the Swing GUI and TCP/IP sockets to communicate with a TCP server on the mainframe. This was a RACF security program that enabled users to update their password on the IBM mainframe without requiring a TSO emulator on the PC.
2001 HypoVereinsbank (Munich, D)	In 2001, I had an assignment at the HypoVereinsbank in Munich to investigate the feasibility of using Java on the z/OS platform. This included developing a pilot application that involved language communication between Java and the other programming languages that were in common use on the mainframe (primarily C, Cobol and PL/1). This communication was accomplished using the Java Native Interface (JNI) and z/OS Language Environment (LE).