Recently we have exercised this with a partner. It may be helpful for others as well.
The basic functionality is to connect to SAP through SAPJCo (Supporting SAPJCo 3.07+).
As a first step have a production with at least two items of the following type:
Configure the settings for the Java Gateway and the SAP Operation accordingly. And start the production.
Now the library sapjco3.jar needs to get imported to be used by further internal functionality.
Therefore start in a browser the webpage for simplified SAPJCo base installation
/csp/<your sapjco namespace>/EnsPortal.Dialog.SAPJCO.BaseConfiguration.cls.
Name the SAPJCo-Operation just in the wizard (in our case it is called „SAPJCoOperation“ within the production).
As the next step, you'll import the Java library e.g. "C: \sapjco\JCO3_64\sapjco3.jar". You need to get a version from the owner of the SAP system (the SAP system owner is entitled to download it from SAP Marketplace).
Now almost all relevant information to import the sapjco3.jar is available. Open the „Import sapjco3.jar“. A click on the textfield will start a filedialog. Point it tot he jar-file.
By clicking on the Import sapjco3.jar button the proxy classes will be generated. After the successful import you should see the following screen:
Now the real work may begin.