Starting the VMC Debugger 

Use

In the context of VMC debugging, there are a number of ways to start debugging, depending on the purpose for which you are debugging. The following describes the possibilities that are relevant for application debugging:

●      Debugging of VMC function modules from an ABAP debugging session

If you come across a VMC function module during an ABAP debugging session, a window automatically appears containing the connection information for the VMC Debugger. You then have the choice of whether to perform the debugging in Eclipse, NWDI, or in the VMC Debugger.

●      Debugging a VMC VM

You can use transaction SM52 to set a selected VM of the VM container into debug mode.

This type of debugging is only listed here for reasons of completeness, since it is usually only of interest for the developer of the VM itself. No additional information about this is provided in this documentation.

Advantages of VMC Debugging

Eclipse and NWDI are usually locally installed, and the source files of a VMC application need to be accessed by these tools using a file system. This can lead to a situation in which different code statuses exist in the locally-installed tool and in the system requiring support. Long connection routes from the locally-installed Eclipse/NWDI to the VMC VM can also lead to connection terminations.

With the VMC Debugger, you can avoid these problems, since this debugger was conceived specifically to filter out exactly the information that is required with the minimum of effort. The VMC Debugger runs directly on the SAP system with the VM to be debugged. To use the Debugger you require only an SAP GUI for display. The source files of the VMC application can be stored in the database of the SAP system.

Prerequisites

You require only an SAP GUI.

Procedure

As described above, you can start the VMC Debugger at the appropriate point from your ABAP debugging session. As soon as a VMC function module is started using the step-in command of the ABAP Debugger, a window showing connection information appears. If you decide to use the VMC Debugger for the debugging, you only need to open transaction VMCDJB in another session to start the VMC Debugger. 

Result

You have started the VMC Debugger. The section Navigating in the VMC Debugger describes how you can obtain the desired information in the VMC Debugger.

Example

An ABAP report that also accesses VMC function modules is started in debug mode. The VMC system debugging is automatically activated if the ABAP system debugging is activated by choosing Settings → System Debugging. System debugging allows access to additional VM resources, such as Java threads that a VMC VM requires for its own operation.

As soon as a VMC function module is started using the step-in command of the ABAP Debugger, a window showing connection information to the backend appears, as shown in the figure below:

You now only need to open transaction VMCJDB in another session, and the initial screen for the VMC Debugger appears.

The possible backend connections are shown under available connections.

You can create a connection to the backend system by double-clicking attach.

More information about navigating in the VMC Debugger: Navigating in the VMC Debugger.