/sap-abap

ABAP Exception Handling - Complete Reference

Source: https://github.com/SAP-samples/abap-cheat-sheets/blob/main/27_Exceptions.md

Exception Class Hierarchy

All exception classes inherit from one of three abstract superclasses, all derived from CX_ROOT:

CX_STATIC_CHECK

• Must be handled locally or declared in procedure interface
• Compile-time static checks enforce handling
• Example: CX_UUID_ERROR

" Declaration in method signature
METHODS get_uuid
  RETURNING VALUE(uuid) TYPE sysuuid_x16
  RAISING cx_uuid_error.

" Calling code must handle
TRY.
    DATA(uuid) = get_uuid( ).
  CATCH cx_uuid_error.
    " Handle exception
ENDTRY.

CX_DYNAMIC_CHECK

• For exceptions preventable through preconditions
• No compile-time enforcement
• Runtime checks only when exception is raised
• Example: CX_SY_ZERODIVIDE

" Declaration (optional but recommended)
METHODS divide
  IMPORTING num1 TYPE i num2 TYPE i
  RETURNING VALUE(result) TYPE decfloat34
  RAISING cx_sy_zerodivide.

CX_NO_CHECK

• For errors that can occur anytime
• Always implicitly declared in all interfaces
• Cannot be prevented by checks
• Example: Memory shortage

Exception Class Components

Inherited Methods (from CX_ROOT)

" Get exception text
DATA(text) = exception->get_text( ).

" Get source position
exception->get_source_position(
  IMPORTING
    program_name = DATA(program)
    include_name = DATA(include)
    source_line  = DATA(line) ).

Common Attributes

• textid: Key for exception text in T100 table
• previous: Reference to previous exception (chaining)
• is_resumable: Flag for resumable exceptions

TRY-CATCH Structure

Basic Syntax

TRY.
    " Risky code
    DATA(result) = 1 / 0.
  CATCH cx_sy_zerodivide.
    " Handle division by zero
ENDTRY.

Multiple Exception Types

TRY.
    " Code that might raise various exceptions
  CATCH cx_sy_zerodivide cx_sy_arithmetic_overflow.
    " Handle arithmetic errors
  CATCH cx_sy_conversion_error.
    " Handle conversion errors
  CATCH cx_root.
    " Handle any exception
ENDTRY.

CATCH INTO (Get Exception Object)

TRY.
    DATA(line) = itab[ 999 ].
  CATCH cx_sy_itab_line_not_found INTO DATA(exc).
    DATA(msg) = exc->get_text( ).
    exc->get_source_position(
      IMPORTING
        program_name = DATA(prog)
        source_line  = DATA(line_no) ).
ENDTRY.

Exception Hierarchy

" Use parent class to catch multiple child exceptions
TRY.
    DATA(result) = 1 / 0.
  CATCH cx_sy_arithmetic_error.
    " Catches both CX_SY_ZERODIVIDE and CX_SY_ARITHMETIC_OVERFLOW
ENDTRY.

Raising Exceptions

RAISE EXCEPTION TYPE

RAISE EXCEPTION TYPE cx_sy_zerodivide.

With Exception Object

DATA(exc) = NEW cx_sy_zerodivide( ).
RAISE EXCEPTION exc.

" Inline
RAISE EXCEPTION NEW cx_sy_zerodivide( ).

With Parameters

RAISE EXCEPTION TYPE zcx_my_error
  EXPORTING
    textid = zcx_my_error=>specific_error
    param1 = 'value1'
    param2 = 'value2'.

In COND/SWITCH

DATA(result) = COND string(
  WHEN valid THEN process( )
  ELSE THROW zcx_validation_error( ) ).

DATA(value) = SWITCH #( code
  WHEN 1 THEN 'A'
  WHEN 2 THEN 'B'
  ELSE THROW zcx_invalid_code( ) ).

CLEANUP Block

Executes when exception raised but handled externally:

TRY.
    TRY.
        " Inner TRY
        process_data( ).
      CATCH cx_sy_zerodivide.
        " Handle locally
      CLEANUP.
        " Cleanup when exception propagates out
        cleanup_resources( ).
    ENDTRY.
  CATCH cx_sy_itab_line_not_found.
    " Handle external exception
ENDTRY.

CLEANUP INTO

CLEANUP INTO DATA(cleanup_exc).
  DATA(exc_class) = cl_abap_classdescr=>get_class_name( cleanup_exc ).
  " Perform cleanup based on exception type

RETRY Statement

Exits CATCH block and restarts TRY block:

DATA retry_count TYPE i.
TRY.
    result = risky_operation( ).
  CATCH cx_sy_zerodivide.
    retry_count += 1.
    IF retry_count < 3.
      RETRY.  " Restart TRY block
    ENDIF.
ENDTRY.

Resumable Exceptions

Declaration

METHODS process
  RAISING RESUMABLE(zcx_my_resumable_error).

Raising Resumable

METHOD process.
  IF error_condition.
    RAISE RESUMABLE EXCEPTION TYPE zcx_my_resumable_error.
    " Execution continues here if RESUME called
    result = fallback_value.
  ENDIF.
ENDMETHOD.

CATCH BEFORE UNWIND

TRY.
    process( ).
  CATCH BEFORE UNWIND zcx_my_resumable_error INTO DATA(exc).
    IF exc->is_resumable = abap_true.
      log_warning( exc->get_text( ) ).
      RESUME.  " Continue after RAISE statement
    ENDIF.
ENDTRY.

In COND/SWITCH

DATA(value) = COND #(
  WHEN condition THEN result
  ELSE THROW RESUMABLE zcx_my_error( ) ).

Exception Chaining (PREVIOUS)

TRY.
    TRY.
        RAISE EXCEPTION TYPE cx_sy_zerodivide.
      CATCH cx_sy_zerodivide INTO DATA(inner).
        RAISE EXCEPTION TYPE cx_sy_arithmetic_overflow
          EXPORTING previous = inner.
    ENDTRY.
  CATCH cx_sy_arithmetic_overflow INTO DATA(outer).
    " Access chain
    DATA(current) = CAST cx_root( outer ).
    WHILE current IS BOUND.
      out->write( current->get_text( ) ).
      current = current->previous.
    ENDWHILE.
ENDTRY.

Using Messages as Exception Texts

IF_T100_MESSAGE Interface

" Exception class with T100 messages
CLASS zcx_my_error DEFINITION INHERITING FROM cx_static_check.
  PUBLIC SECTION.
    INTERFACES if_t100_message.

    CONSTANTS:
      BEGIN OF error_001,
        msgid TYPE symsgid VALUE 'ZMSG',
        msgno TYPE symsgno VALUE '001',
        attr1 TYPE scx_attrname VALUE '',
        attr2 TYPE scx_attrname VALUE '',
        attr3 TYPE scx_attrname VALUE '',
        attr4 TYPE scx_attrname VALUE '',
      END OF error_001.
ENDCLASS.

IF_T100_DYN_MSG Interface (Recommended)

[7.50+] IF_T100_DYN_MSG and the MESSAGE addition to RAISE EXCEPTION/THROW require ABAP 7.50 or higher. On 7.40, use IF_T100_MESSAGE with explicit textid instead.

" With MESSAGE addition
RAISE EXCEPTION TYPE zcx_error
  MESSAGE e002(zmsg).

" With placeholder values
RAISE EXCEPTION TYPE zcx_error
  MESSAGE e003(zmsg) WITH 'value1' 'value2'.

" MESSAGE ID TYPE NUMBER WITH
RAISE EXCEPTION TYPE zcx_error
  MESSAGE ID 'ZMSG' TYPE 'E' NUMBER '004'
  WITH value1 value2.

" USING MESSAGE (from sy-msg* fields)
MESSAGE e005(zmsg) WITH 'param' INTO DATA(msg).
RAISE EXCEPTION TYPE zcx_error USING MESSAGE.

In COND/SWITCH

DATA(result) = COND #(
  WHEN valid THEN value
  ELSE THROW zcx_error( MESSAGE e001(zmsg) ) ).

DATA(result) = SWITCH #( code
  WHEN 1 THEN 'A'
  ELSE THROW zcx_error(
    MESSAGE ID 'ZMSG' TYPE 'E' NUMBER '002'
    WITH code ) ).

Runtime Errors

RAISE SHORTDUMP

" Force runtime error
RAISE SHORTDUMP TYPE cx_sy_zerodivide.

In COND/SWITCH

DATA(result) = COND #(
  WHEN valid THEN value
  ELSE THROW SHORTDUMP zcx_critical_error( ) ).

Assertions

" Assert condition - fails = runtime error ASSERTION_FAILED
ASSERT count > 0.
ASSERT table IS NOT INITIAL.
ASSERT ref IS BOUND.

Common Exception Classes

RAP Messages (%msg)

" In RAP handler methods
reported-root = VALUE #( (
  %tky = entity-%tky
  %msg = new_message_with_text(
    severity = if_abap_behv_message=>severity-error
    text = 'Validation failed!' ) ) ).

" Severity levels
" if_abap_behv_message=>severity-error
" if_abap_behv_message=>severity-warning
" if_abap_behv_message=>severity-information
" if_abap_behv_message=>severity-success

Best Practices

1. Choose appropriate exception category

   • CX_STATIC_CHECK: Must be handled explicitly
   • CX_DYNAMIC_CHECK: Preventable errors
   • CX_NO_CHECK: System errors

2. Use specific exception classes rather than CX_ROOT

3. Include meaningful information in exception text

4. Use PREVIOUS for exception chaining

5. Custom attributes should be READ-ONLY

6. Document exceptions in method signatures

7. Handle exceptions at appropriate level - not too early, not too late