Debugging is one of the essential skills an SAP programmer needs. It can help you resolve errors and bugs in your programs and make understanding the flow of ABAP code easier. Debugging is a process that allows you to step through your code line by line, set breakpoints, examine variables and program call stack watch expressions, etc.
1. Watchpoints
Watchpoints are particular breakpoints you can set to scan for changes in concrete variables. You can use them to monitor several things, such as the content of an internal table. Watchpoints can help debug your SAP ABAP programming without changing the source code or the application itself.
For example, you can set a watchpoint on an internal table to stop the Debugger once incorrect data records are inserted. You can also create watchpoints on individual fields in a program. You can add a watchpoint by placing the cursor at the desired variable in the editor and executing the context menu. Once you’ve added a watchpoint, you can activate or deactivate it during a debugging session.
Moreover, you can compare the variable’s old value to its new state. The watchpoint will be displayed in the Breakpoints tool (desktop Breakpoints/Watchpoints / Tab Watchpoints). You can view a reached watchpoint in detail. It is important to remember that ABAP watchpoints are short-lived and can only be active within an active Debugger session. If the internal session ends, all the existing watchpoints will disappear automatically. However, they can be reactivated once the internal session is restarted.
2. Breakpoints
Breakpoints in the ABAP program source code tell the runtime processor to stop the program at a specific point and start the Debugger. They can be set in the ABAP Editor or the Debugger, depending on how you want to use them.
In ABAP programs, you can also set watchpoints to monitor the contents of specific fields when the contents of a field change, the watchpoint triggers, and the program is interrupted. These can be defined in the ABAP Editor or SAP’s Debugger window. To set a watchpoint, select the line of code at which you want to set the breakpoint and click on one of the icons above.
Then, choose which one you want to use and then click OK. Watchpoints are similar to breakpoints but monitor a specific variable and interrupt the program when it changes. They can be set in the ABAP editor or directly in the Debugger, and you can specify the conditions on which they become active. Unlike breakpoints, watchpoints are only valid during the current debugging session.
They will remain active until you log off or remove them from the debugger or Abap editor. In addition to breakpoints, there are external breakpoints (formerly known as user breakpoints). They apply to the current user session and remain valid for future user sessions. They are beneficial for RFC, ICF, and APC processing.
3. Variables
Variables are data objects that users can change the contents of with ABAP statements. Each variable has a specific type, which determines the size and layout of its memory, the range of values it can store, and the set of operations that can be applied to it.
When you want to debug an ABAP program, you can create one or more breakpoints in the program code. These breakpoints tell the ABAP runtime processor to interrupt processing and start the Debugger. There are two types of breakpoints in ABAP: Static and Dynamic.
Static breakpoints are not user-specific and are constantly interrupted when the runtime processor reaches the line at which the breakpoint is placed. Using the ABAP statement BREAKPOINT, you can set static breakpoints in the ABAP Editor or directly in the Debugger. You can also define a counter and activate the breakpoint only after it has been reached a specified number of times.
Particular dynamic breakpoints are helpful when interrupting a program directly before a detailed ABAP statement, subroutine, or event. You can also use these breakpoints to stop programs immediately after a runtime error has occurred. The ABAP debugger enables you to navigate through all of an ABAP program’s structure and function modules. The SAP system also displays the components of structures and functions.
4. Subroutines
Subroutines are a fundamental part of computer programming. They break a complex programming task into smaller steps that can be called independently. They also make debugging easier as programmers can look at each step individually and find out where errors might have occurred.
When a programmer uses subroutines, it is essential to know what parameters they will be given and how they will be returned to the calling program. These details must be specified to avoid a subroutine being called with too many parameters or bearing incorrect data. An excellent way to define subroutines is to use pseudo-code, which provides a graphical interface for the programmer to see how they will work.
You can then follow this with more detailed code to test it in the real world. You can also use subroutines to return multiple values to the primary (calling) program. This requires creating a tuple, a short list of values that are grouped temporarily.
The subroutine then retunes these to the main program once presented in the same order as in the tuple. Using subroutines is essential for programmers to learn as they progress through their academic careers and into the workplace. They are necessary for writing programs with excellent overall function and transparency.
