Many SAP projects require integration with external systems such as payment gateways, logistics platforms, mobile applications, cloud services, and third-party portals. I want to learn the complete process of sending data from SAP to an external REST API and reading the response in ABAP.

Please help with the following points:

• What is a REST API and how is it different from SOAP web services?
• How can we call a REST API from ABAP using CL_HTTP_CLIENT?
• How can we send GET, POST, PUT, and DELETE requests?
• How can we add HTTP headers such as Content-Type, Authorization, API Key, and Bearer Token?
• How can we send JSON data in a POST request from ABAP?
• How can we convert an ABAP structure or internal table into JSON format?
• How can we read and deserialize a JSON response into an ABAP structure?
• How can we handle HTTP response codes such as 200, 201, 400, 401, 404, and 500?
• How can we troubleshoot SSL certificate, authorization, timeout, and connection errors?
• What is the best way to store API URLs, credentials, and tokens securely in SAP?
• Can someone share a complete working ABAP example for calling a REST API and processing the JSON response?

A beginner-friendly explanation with complete ABAP code, error handling, and a real project example would be very helpful.

I need a simple and practical explanation of how to display data from an internal table in an ALV grid. I also want to understand how to improve the report by adding useful features such as column headings, sorting, filtering, totals, and layout options.

Please help with the following points:

• What is CL_SALV_TABLE and when should it be used instead of REUSE_ALV_GRID_DISPLAY or CL_GUI_ALV_GRID?
• How can we create a basic ALV report using an internal table?
• How can we define column texts and hide unwanted columns?
• How can we enable sorting, filtering, and standard toolbar functions?
• How can we add totals and subtotals for numeric fields?
• How can we set zebra pattern, optimize column width, and change the ALV title?
• How can we handle exceptions while creating an ALV object?
• How can we add a hotspot or clickable column in CL_SALV_TABLE?
• What are the limitations of CL_SALV_TABLE, especially for editable ALV reports?
• Can someone share a complete working ABAP example with sample data?

A beginner-friendly, step-by-step guide with complete ABAP code and explanation would be very helpful.

I want to learn how to analyze and fix ABAP dumps in a simple, practical way.

Please help with the following points:

• What is an ABAP short dump and why does it occur?
• How can we read the important sections of an ST22 dump, such as Runtime Errors, Error Analysis, Source Code Extract, and Active Calls/Events?
• How can we identify the exact program, include, method, function module, and line number causing the error?
• What are the common ABAP dump errors, such as GETWA_NOT_ASSIGNED, ITAB_DUPLICATE_KEY, CONVT_NO_NUMBER, DBSQL_SQL_ERROR, TIME_OUT, and TSV_TNEW_PAGE_ALLOC_FAILED?
• How can we fix a field symbol not assigned error or a null object reference error?
• How can we handle conversion errors when a character value is moved to a numeric field?
• How can we prevent internal table duplicate key errors?
• How can we troubleshoot database-related dumps and authorization-related dumps?
• When should we use TRY...CATCH, IF ... IS ASSIGNED, IS BOUND, and validation checks to prevent dumps?
• How can we reproduce the issue safely in development or quality systems before fixing it in production?

A beginner-friendly explanation with real ABAP code examples, common dump scenarios, and troubleshooting steps would be very helpful.

I know that breakpoints can be used, but I want to understand the complete debugging process in a simple and practical way.

For example, I want to know how to find why an internal table is empty, why a SELECT statement is not returning data, why an IF condition is not working, or why sy-subrc has an unexpected value.

Please help with the following points:

• How can we start debugging an ABAP report, function module, class method, BAdI, user exit, or enhancement?
• What is the difference between session breakpoint and external breakpoint?
• When should we use a breakpoint, watchpoint, or conditional breakpoint?
• How can we debug a background job, RFC call, update task, IDoc, or Web Dynpro application?
• How do we check variable values, internal tables, structures, field symbols, and references in the ABAP debugger?
• How can we identify why a SELECT statement returns no records?
• How can we use sy-subrc correctly while debugging?
• How can we skip code, change variable values temporarily, or move the execution pointer during debugging?
• What are the most useful debugger shortcuts and tips for beginners?
• What are common ABAP debugging mistakes and how can they be avoided?

A simple step-by-step explanation with real examples, screenshots, and common troubleshooting scenarios would be very helpful.

*&---------------------------------------------------------------------*
*& Report  ZTEST_PROGRAM_2
*&
*&---------------------------------------------------------------------*
*&
*&
*&---------------------------------------------------------------------*

REPORT ztest_program_2.

*--- Radio Buttons
PARAMETERS: r_opt1 RADIOBUTTON GROUP grp DEFAULT 'X' USER-COMMAND rad,
            r_opt2 RADIOBUTTON GROUP grp,
            r_opt3 RADIOBUTTON GROUP grp.

*--- Fields controlled by radio buttons
PARAMETERS: p_field1 TYPE char20,
            p_field2 TYPE char20,
            p_field3 TYPE char20.

*--- Screen Modification
AT SELECTION-SCREEN OUTPUT.
LOOP AT SCREEN.
CASE screen-name.
WHEN 'P_FIELD1'.
screen-active = COND #( WHEN r_opt1 = 'X' THEN 1 ELSE 0 ).
WHEN 'P_FIELD2'.
screen-active = COND #( WHEN r_opt2 = 'X' THEN 1 ELSE 0 ).
WHEN 'P_FIELD3'.
screen-active = COND #( WHEN r_opt3 = 'X' THEN 1 ELSE 0 ).
ENDCASE.
MODIFY SCREEN.
ENDLOOP.

*--- Output
START-OF-SELECTION.
WRITE: / 'Option 1:', r_opt1,
         / 'Option 2:', r_opt2,
         / 'Option 3:', r_opt3,
         / 'Field1:', p_field1,
         / 'Field2:', p_field2,
         / 'Field3:', p_field3.

Output:

This ABAP program ZRADIO_DEMO demonstrates how to create a dynamic selection screen using radio buttons. It defines three radio buttons, where only one can be selected at a time, and three corresponding input fields (p_field1, p_field2, p_field3). The logic inside the AT SELECTION-SCREEN OUTPUT event uses a LOOP AT SCREEN to check which radio button is active and then enable or disable the related input field accordingly, making the other fields invisible. This ensures that only the field relevant to the selected option is shown to the user. Finally, in the START-OF-SELECTION block, the program outputs the selected option and the entered values. Overall, the code provides a simple but effective example of how to use radio buttons to control screen modifications in SAP reports, making the user interface more interactive and user-friendly.