report z.

data: g_s_log            type bal_s_log,
      g_dummy.

data: begin of probclass,
        very_high type bal_s_msg-probclass value '1',
        high      type bal_s_msg-probclass value '2',
        medium    type bal_s_msg-probclass value '3',
        low       type bal_s_msg-probclass value '4',
        none      type bal_s_msg-probclass value is initial,
      end of probclass.

start-of-selection.
*******************

* I. Create application log:
  g_s_log-extnumber = 'Application Log Example'.
  g_s_log-aluser    = sy-uname.
  g_s_log-alprog    = sy-cprog.
  call function 'BAL_LOG_CREATE'
    EXPORTING
      I_S_LOG                       = g_s_log
*   IMPORTING
*     E_LOG_HANDLE                  =
    EXCEPTIONS
      LOG_HEADER_INCONSISTENT       = 1
      OTHERS                        = 2.
  case sy-subrc.
    when 1. message e398(00) with 'Cannot create log: bad log header'.
    when 2. message e398(00) with 'Cannot create log'.
  endcase.

* II. Add messages to the log:
* issue message and add to log
  message s398(00) with 'message 1:' 'very important info'.
  perform msg_add using probclass-very_high sy-msgty sy-msgid sy-msgno
                        sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
* issue message to dummy (not to user) and add to log
  message e398(00) with 'message 1:' 'important info'
          into g_dummy.
  perform msg_add using probclass-high sy-msgty sy-msgid sy-msgno
                        sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
* directly add to log
  perform msg_add using probclass-medium 'W' '00' '398'
                        'info' space space space.
  perform msg_add using probclass-low 'I' '00' '398'
                        'just FYI' space space space.
  perform msg_add using probclass-none 'I' '00' '398'
                        '????' space space space.

* III. Display application log:
  call function 'BAL_DSP_LOG_DISPLAY'
     exceptions
       profile_inconsistent = 1
       internal_error       = 2
       no_data_available    = 3
       no_authority         = 4.
  case sy-subrc.
    when 1. message e398(00) with 'Cannot display log: bad profile'.
    when 2. message e398(00) with 'Cannot display log: internal error'.
    when 3. message e398(00) with 'Cannot display log: no data'.
    when 4. message e398(00) with 'Cannot display log: no authority'.
  endcase.

********************************************************************
form msg_add using value(p_probclass) type bal_s_msg-probclass
                   value(p_msgty)     like sy-msgty
                   value(p_msgid)     like sy-msgid
                   value(p_msgno)     like sy-msgno
                   value(p_msgv1)     like sy-msgv1
                   value(p_msgv2)     like sy-msgv2
                   value(p_msgv3)     like sy-msgv3
                   value(p_msgv4)     like sy-msgv4.
  data l_s_msg type bal_s_msg.

  l_s_msg-msgty     = p_msgty.
  l_s_msg-msgid     = p_msgid.
  l_s_msg-msgno     = p_msgno.
  l_s_msg-msgv1     = p_msgv1.
  l_s_msg-msgv2     = p_msgv2.
  l_s_msg-msgv3     = p_msgv3.
  l_s_msg-msgv4     = p_msgv4.
  l_s_msg-probclass = p_probclass.

  call function 'BAL_LOG_MSG_ADD'
    EXPORTING
*     I_LOG_HANDLE              =
      I_S_MSG                   = l_s_msg
*   IMPORTING
*     E_S_MSG_HANDLE            =
*     E_MSG_WAS_LOGGED          =
*     E_MSG_WAS_DISPLAYED       =
    EXCEPTIONS
      LOG_NOT_FOUND             = 1
      MSG_INCONSISTENT          = 2
      LOG_IS_FULL               = 3
      OTHERS                    = 4.
  case sy-subrc.
    when 1. message e398(00) with 'Cannot add msg: log not found'.
    when 2. message e398(00) with 'Cannot add msg: bad msg'.
    when 3. message e398(00) with 'Cannot add msg: log full'.
    when 4. message e398(00) with 'Cannot add msg'.
  endcase.

endform.
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