The New ABAP Debugger was first released by SAP with NetWeaver04. As of release NetWeaver 7.0 it fully replaces in the scope of its functionality the "old-fashioned" Classic ABAP Debugger. During the last SAP TechEds I learned that more and more people use the New ABAP Debugger (that is a great news!) but still many are not aware of some of its useful features. The purpose of this blog is to point you to these features so that you can make the most of the New ABAP Debugger.
- Some useful debugger settings
- How to handover a debugger problem - Use Debugger Variants
- How to display all loaded programs and global variables - Use the Loaded Programs Tool
- How to test a function module in the debugger and pass parameters
- Helpful hints for analyzing variables
- How to debug a program which is running in an endless loop
- How to debug a background job which is running in an endless loop
- How to debug a finished or crashed background job
- How to compare ABAP variables - Use the Diff Tool
- How to debug HTTP requests
- Helpful debugger ok-codes
Some useful debugger settings
The New ABAP Debugger settings dialog lets you activate special debugging modes and comfort options that can speed up your troubleshooting scenarios. Here you will find some helpful debugger settings with instructions on when and how to use them. You can access debugger settings in the debugger by using Settings->Display/Change Debugger Settings:
- System Debugging: if you have problems that involve system programs (such as a function that can't be accessed in the debugger), turn on this setting (or use menu Settings->System debugging On/Off " or the command /hs in the debugger command field). You can declare a program as a system program by setting Status to "System Program" in its attributes in the ABAP Editor (SE38) (check the radiobutton Attributes and press Change button).
- Update Debugging: turn on this setting if you need to analyze asynchronous updates, which are functions that are called as follows: CALL FUNCTION ‘...' IN UPDATE TASK. These functions are executed asynchronously in a special update work process (after the next COMMIT WORK statement). The debugger can't follow them since it is attached to a single process. Set a breakpoint in the function that is called IN UPDATE TASK, start debugging, turn on this setting, and the debugger will reach the breakpoint in your update function.
- TRFC (In Background Task): Block Sending: turn on this setting if you need to analyze transactional Remote Function Calls (TRFC), which are called as follows: CALL FUNCTION ‘...' IN BACKGROUND TASK. These functions are called asynchronously, along with other TRFC functions of this logical unit of work (LUW), after the next COMMIT WORK statement. The debugger can't follow them since it is attached to a single process. When you turn on this setting, these TRFC functions are stored in the system for debugging instead of being sent. Use the TRFC Monitor (transaction SM58) to analyze the unprocessed LUWs and select Edit->Debug LUW to debug them.
- Close debugger After ‘Continue' (F8) and Roll Area End: usually after you press Continue (F8) in the debugger session, the debugger session remains available but inactive when the program is finished. If you switch on this setting, then the debugger will be closed automatically after pressing Continue (F8), when the roll area (internal session) is ended.
- Always Create Exception Obj.: turn on this setting if you need to analyze exception objects (if you catch ABAP exceptions in your program via the CATCH CX_MY_EXCEPTION without specifying a reference variable to which the exception object can be assigned). You can then examine the created exception objects in the debugger via Display Exception Obj. magnifier button.
How to handover a debugger problem - Use Debugger Variants
Imagine that you have had to reproduce and troubleshoot a problem in a rather complicated environment. You have finally found the function module which doesn't work properly under certain conditions. You may need to hand over this debugging session for further analysis to a colleague who has expert knowledge of this function module.
In order to ensure that your colleague can reproduce the problem, you must create a very detailed description: the source lines at which to set breakpoints, the debugger settings that must be active, and so on. This is time consuming and there is still a chance that you might forget critical information. In such situations, use a debugger variant (menu Debugger->Debugger Session->Save) to store your debugger session. You can choose which parts to store: current layout (customized desktops), debugger settings, options and breakpoints. Then you can save the variant either in the database or in a local file and send it per email to your colleague.
Afterwards your colleague can load the saved variant from a file or the database after starting a debugging session (menu Debugger->Debugger Session->Load). All settings and breakpoints will become active immediately. Of course he can choose which components of the variant to load: layout, settings, options, breakpoints, or all of them.
How to display all loaded programs and global variables - Use the Loaded Programs Tool
A double-click on the variable name in the source code leads to the Variable Fast Display Tool where you get information about variable: type, value, etc. On the Locals tab you get all parameters (including parameter kind) and local variables of the current function module, on the Globals tab, you can display all global variables of the current program. But sometimes this local and global information is not enough; you maybe need to display all currently loaded programs and their global variables as well. For this purpose, use the Loaded Programs Tool (button New Tool, Special Tools->Loaded Programs).
Loaded Programs shows you two tabs. On the Loaded Programs tab you see the attributes of all loaded programs and their program groups. On the Global Data tab you get global variables of each global program just by double-clicking the program in the navigation tree.
How to test a function module in the debugger and pass parameters
Imagine you want to test a function module in the test framework of the Function Builder (transaction SE37) in the debugger, and you need to pass as a parameter a big internal table with many entries. It would be very time consuming to enter the input data for such a table manually in SE37. But you don't have to do this. If you access the function module from the debugger, then you can download its parameters to the SE37 test framework. Select the parameter and use the right mouse button context menu Save Parameters as Test Data (SE37). Please consider that this download is restricted to the data types which are allowed in the SE37 test framework: you cannot download objects, nested internal tables or data references. After that just open the function module in a separate SE37 window and run it in the test framework. You can access your downloaded data in SE37 via Test Data Directory button.
Helpful hints for analyzing variables
- Use the Data Explorer to view deep nested objects With the Objects Tool (Objects desktop) you can examine object properties including visibility, inheritance, references to the object (where-used list ). You can double-click on attributes in order to navigate to the subcomponents of a class. But if you have to analyze deep nested objects, then the Data Explorer Tool is the better choice. The Data Explorer lets you drill down into nested objects, structures, and references without losing context of the upper levels.
- Use Text Translation to display large hex strings and the XML Browser to display XML data. It is very time consuming to analyze the content of a variable that contains 2000 bytes of hex code. Therefore, the detail view (Detail Display desktop) for simple types and strings allows you to translate hex strings into readable text using the appropriate code page (field View , choose Text Translation). For binary XML data, there is the XML viewer (field View , choose XML Browser).
How to debug a program which is running in an endless loop
Imagine your program is running in an endless loop and you need to analyze its behavior. In such situations you can force the running program into the debugger simply by setting a session breakpoint in a second ABAP Editor. In Utilities->Settings...->Debugging just choose the Session breakpoint active immed. option. When you activate this option, all (running and waiting) sessions of your logon session immediately inherit all session breakpoints set in any of those sessions. It is recommended that you activate this option in development environments.
How to debug a background job which is running in an endless loop
Now imagine that you have a background job that is running and running, and you want to analyze its behavior. Just use the Process Overview (transaction SM50), select the running process, and choose from the transaction menu Program->Debugging.
How to debug a finished or crashed background job
Now just imagine that your background job finishes its execution so quickly, that you don't have a chance to attach a debugger to it in the Process Overview (SM50), or even worse: it crashed with a dump and you need to analyze what caused the dump. Just choose your job in the Job Overview (transaction SM37) and type "jdbg" into the command field. The debugger will start, and you just would need to press a couple of times Return (F7) to get out of the spool functions checks and you can debug your finished or crashed background job online in dialog.
How to compare ABAP variables - Use the Diff Tool
Just imagine you are in the debugger and need to compare two strings which are 2000 bytes long, or you need to compare two nested objects to look for differences in deeply nested attributes. With the Diff Tool (Diff Desktop) you can compare two compatible ABAP variables, e.g. two tables, objects, structures or strings. The Diff tool provides differences concerning type and value. If you double click on a hit in the diff result list, the variables are displayed in parallel, and the debugger navigates to the difference.
In order to assure good performance of the diff tool, even for deeply nested variables no "deep diff" is executed.
This means that if you have for example an internal table as the attribute of an object, then you can at first only check if the tables of both objects are equal. You will not get details about where they differ. To get the details of differences, you can run a diff for the unequal subcomponents (Diff button in the corresponding result line). You can use the History tab to get back to the first result list.
How to debug HTTP requests
Nowadays, distributed HTTP based applications (like BSP, Web Dynpro for ABAP applications) are the reality in many IT scenarios. To troubleshoot such applications, you must be able to debug HTTP requests.
Use transaction SICF to activate the debugger for a specific web service and a specific user (menu Edit->Debugging->Acivate Debugging). Please keep in mind that your web application must run on the server where you set user breakpoints and/or where you activate HTTP debugging via SICF. Please refer to SAP note 668256 for the details on HTTP debugging.
After activating debugging, you will stop in the system code of the http requests in the debugger.
Helpful debugger ok-codes
/h activate debugging
/hs activate system debugging
/ha skip dynpro (PAI, PBO) and directly debug ABAP code
/hx detach debugger
/hmusa create memory snapshot (can be used in the transaction S_MEMORY_INSPECTOR for memory consumption analysis)
jdbg in SM37 restart of a finished or crashed background job for debugging
/ron start ABAP Runtime Analysis measurement (transaction SE30)
/roff stop ABAP Runtime Analysis measurement (transaction SE30)