In an AS ABAP and AS Java combined system, the server components reside on the same host and therefore use the same fully-qualified host name for access. In this case, create the key pair on the ABAP server and export it so that you can upload it onto the J2EE Engine.
Using the trust manager (transaction STRUST):
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1. If the server does not already possess a key pair to use for SSL, then create the SSL server PSE for the system.
Depending on how the server is to be accessed, you can create a system-wide PSE or server-specific PSEs. For more information, see Configuring the SAP Web AS for Supporting SSL.
2. Select the SSL server PSE to use for the J2EE Engine.
To select the system-wide SSL server PSE, select the SSL server PSE node with a double-click. To select a server-specific PSE, expand the SSL server PSE node and select the application server with a double-click.
3. Choose PSE → Export and save the PSE file to a local directory.
4. Use the command line tool sapgenpse to export the PSE's key pair from this file to a file in PKCS#12 format.
sapgenpse export_p12 [options] -p <pse file> <filename>.p12
For more information, see Exporting a PKCS#12 File.
You can now upload this key pair onto the J2EE Engine using the Key Storage service.