More complex JCO Server examples (ABAP to Java)

Question

JCo connections:
I found a couple of good documents for connecting from Java to ABAP. Whenever it comes to the other direction (ABAP to Java), information is somehow rare.
I had a look at the examples coming with the JCo lib, however I would like to find some more complex examples. Especially the transfer of larger result sets (obtained on the Java side) is interesting.
Does anybody know something like this? I have tried Google, but somehow always the same few articles showed up.
Any hints?

Answer 1

You can also use the JCO RFC Provider Service of the Web Application Server for your ABAP to Java calls.
The steps involved in that are
1. Configure destination in SM59 in SAP.
2. Create RFC Destination in Visual Admin.
3. Create a stateless session bean with JNDI name as the name of calling function module in SAP.
4. Add a business method public void processFunction(JCO.Funtion fn) which is called by the JCO RFC Provider Service. The name should be 'processFunction'.
5. Set library references in application-j2ee-engine.xml to type weak for the following
    a. com.sap.mw.jco.
    b. com.sap.tc.Logging (if you are using the logging api )
Here is the sample code for the EJB biz method
Business Method.
     public void processFunction(JCO.Function function) {
          try {
               // Get the import parameters for the function module
               JCO.ParameterList importList = function.getImportParameterList();
               logger.infoT("The value sent is" +
               (String)importList.getValue("USER_NAME"));
               // Set the export parameter value for the function module
               JCO.ParameterList export = function.getExportParameterList();
               export.setValue("From EJB", "RETURN");
               function.setExportParameterList(export);
          catch (java.lang.Exception e) {
               e.printStackTrace();