zcl_demo_abap_rap_ext_num_m.clas.abap

"! <p class="shorttext"><strong>ABAP EML in a RAP scenario (managed BO)</strong><br/>ABAP cheat sheet example class</p>
"!
"! <p>The example class demonstrates ABAP EML in the context of a RAP demo scenario
"! (managed RAP BO with external numbering). The class represents a RAP BO consumer.<br/>
"! Choose F9 in ADT to run the class.</p>
"!
"! <h2>Note</h2>
"! <ul><li>This class is the RAP BO consumer for a RAP demo scenario that
"! demonstrates various RAP BO standard operations and non-standard
"! operations using ABAP EML in the context of a managed RAP business
"! object with RAP external numbering.</li>
"! <li>Topics covered: RAP BO operations like create (including a
"! determination on save), update, delete, executing an action, validation,
"! create-by-association (parent to child), read (root entity),
"! read-by-association (parent to child), read (child entity),
"! read-by-association (child to parent)</li>
"! <li>Underlying data model: Consists of a root entity and one child entity.
"! The BDEF defines the behavior for these two entities which are connected
"! via a CDS composition relation. The definitions in the BDEF determine
"! which methods must be implemented in the ABAP behavior pool (ABP).</li>
"! <li>ABP for this scenario: {@link zbp_demo_abap_rap_ro_m}.</li>
"! <li> This simplified example is not a real life scenario and rather
"! focuses on the technical side by giving an idea how the communication
"! and data exchange between a RAP BO consumer, which is a class
"! in this case, and RAP BO provider can work. Additionally, it shows
"! how the methods for non-standard RAP BO operations might be
"! self-implemented in an ABP. The example is intentionally kept
"! short and simple and focuses on specific RAP aspects. For this reason,
"! the example might not fully meet the requirements of the RAP BO contract.</li>
"! <li>Find information on <strong>getting started with the example class</strong> and the
"! <strong>disclaimer</strong> in the ABAP Doc comment of class {@link zcl_demo_abap_aux}.</li>
"! </ul>
CLASS zcl_demo_abap_rap_ext_num_m DEFINITION
  PUBLIC
  FINAL
  CREATE PUBLIC .

  PUBLIC SECTION.
    INTERFACES: if_oo_adt_classrun.

    CLASS-METHODS:
      class_constructor.

  PROTECTED SECTION.
  PRIVATE SECTION.
    CLASS-DATA:
      failed   TYPE RESPONSE FOR FAILED zdemo_abap_rap_ro_m,
      reported TYPE RESPONSE FOR REPORTED zdemo_abap_rap_ro_m,
      mapped   TYPE RESPONSE FOR MAPPED zdemo_abap_rap_ro_m,
      op       TYPE string.
    CLASS-METHODS:
      initialize_dbtabs,
      "If there are entries in the response parameters following EML
      "requests, they should be processed for displaying purposes.
      extract_from_reported RETURNING VALUE(messages) TYPE string_table,
      extract_from_failed RETURNING VALUE(errors) TYPE string_table,
      fill_db_tab.

ENDCLASS.



CLASS zcl_demo_abap_rap_ext_num_m IMPLEMENTATION.


  METHOD class_constructor.
    initialize_dbtabs( ).
  ENDMETHOD.


  METHOD extract_from_failed.
    CLEAR errors.

    LOOP AT failed-root ASSIGNING FIELD-SYMBOL(<err>).
      CASE if_abap_behv=>mk-on.
        WHEN <err>-%op-%create.
          op = `create operation`.
        WHEN <err>-%op-%update.
          op = `update operation`.
        WHEN <err>-%op-%delete.
          op = `delete operation`.
        WHEN <err>-%op-%assoc-_child.
          op = `operation involving the child entity`.
        WHEN <err>-%op-%action-multiply_by_2.
          op = `executing action multiply_by_2`.
        WHEN OTHERS. op = `operation`.
      ENDCASE.

      APPEND `Error for instance with ` &&
           COND #( WHEN <err>-%cid IS NOT INITIAL THEN `%cid = `
                   && <err>-%cid
                   ELSE `key = ` && <err>-key_field ) &&
           `: Fail cause ` &&  <err>-%fail-cause && ` for ` &&  op
            && `.` TO errors.
    ENDLOOP.

    IF failed-child IS NOT INITIAL.
      LOOP AT failed-child ASSIGNING FIELD-SYMBOL(<err_ch>).
        APPEND `Error for child instance with key_field = ` &&
        <err_ch>-key_field && ` and key_ch = ` &&
        <err_ch>-key_ch && `: Fail cause `
        && <err_ch>-%fail-cause && `.` TO errors.
      ENDLOOP.
    ENDIF.
  ENDMETHOD.


  METHOD extract_from_reported.
    CLEAR messages.

    LOOP AT reported-root ASSIGNING FIELD-SYMBOL(<rep>).
      IF <rep>-%global = if_abap_behv=>mk-on.
        APPEND <rep>-%msg->m_severity &&
                <rep>-%msg->if_t100_dyn_msg~msgv1 TO messages.
      ELSE.
        APPEND `Message for instance with ` &&
               COND #( WHEN <rep>-%cid IS NOT INITIAL
                       THEN `%cid = ` && <rep>-%cid
                       ELSE `key = ` && <rep>-key_field ) &&
               `: ` &&  <rep>-%msg->m_severity && ` ` &&
               <rep>-%msg->if_t100_dyn_msg~msgv1 TO messages.

      ENDIF.
    ENDLOOP.

    IF reported-child IS NOT INITIAL.
      LOOP AT reported-child ASSIGNING FIELD-SYMBOL(<rep_ch>).
        APPEND `Message for child instance with key_field = ` &&
        <rep_ch>-key_field && ` and key_ch = `
        && <rep_ch>-key_ch && `: ` && <rep_ch>-%msg->m_severity &&
        ` ` && <rep_ch>-%msg->if_t100_dyn_msg~msgv1 TO messages.
      ENDLOOP.
    ENDIF.

  ENDMETHOD.


  METHOD fill_db_tab.
    MODIFY zdemo_abap_rapt1 FROM TABLE @( VALUE #(
          ( key_field = 4
             field1   = 'ggg'
             field2   = 'hhh'
             field3   = 40
             field4   = 41 ) ) ).
  ENDMETHOD.


  METHOD if_oo_adt_classrun~main.

    out->write( |ABAP Cheat Sheet Example: RAP BO Operations Using a Managed RAP BO\n\n| ).

**********************************************************************
*
* Create operation
*
**********************************************************************

    out->write( |1) Create operation\n\n| ).

    "Adding an entry to the database table to provoke an error for the
    "EML create request.
    fill_db_tab( ).

**********************************************************************
* Notes:
* - field4 is purposely not included in the FIELDS list
* - Effect:
*   - %control value for field4 is set to if_abap_behv=>mk-off
*   - Although the derived type (created inline here) includes a
*     value assignment for field4 in an instance, the field value is
*     not saved. The initial value is used.
* - The instance with key_field = 4 will not be saved since an entry
*   already exists in the database table with the same key.
* - Response parameters are specified to receive information.
* - A COMMIT ENTITIES statement triggers the saving of the instances.
* - The example BDEF includes the definition of a determination on
*   save for create operations. In this case, the determination
*   adds some text to the value in field2.
**********************************************************************

    MODIFY ENTITIES OF zdemo_abap_rap_ro_m
      ENTITY root
      CREATE FIELDS ( key_field field1 field2 field3 )
        WITH VALUE #( ( %cid = 'cid1'
                        key_field = 1
                        field1    = 'aaa'
                        field2    = 'bbb'
                        field3    = 10
                        field4    = 11 ) "Value not considered
                      ( %cid      = 'cid2'
                        key_field = 2
                        field1    = 'ccc'
                        field2    = 'ddd'
                        field3    = 20 )
                      ( %cid      = 'cid3'
                        key_field = 3
                        field1    = 'eee'
                        field2    = 'fff'
                        field3    = 30 )
                      ( %cid      = 'cid4' "Instance to fail
                        key_field = 4
                        field1    = 'error'
                        field2    = 'error'
                        field3    = 99 ) )
        MAPPED mapped
        FAILED failed
        REPORTED reported.

    COMMIT ENTITIES.

    IF sy-subrc <> 0.
      out->write( `An issue occurred in the RAP save sequence.` ).
    ENDIF.

    "Retrieving and displaying database content
    SELECT FROM zdemo_abap_rapt1
      FIELDS key_field, field1, field2, field3, field4
      ORDER BY key_field
      INTO TABLE @DATA(tab_root).

    out->write( data = tab_root name = `tab_root` ).
    out->write( |\n| ).

    "Displaying response information
    IF mapped-root IS NOT INITIAL.
      out->write( `Entries in MAPPED response parameter ` &&
                         `(root entity)` ).
      out->write( |\n| ).
      out->write( data = mapped-root name = `mapped-root` ).
      out->write( |\n| ).
    ENDIF.

    IF failed IS NOT INITIAL.
      out->write( `Entries in FAILED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_failed( ) name = `extract_from_failed( )` ).
      out->write( |\n| ).
    ENDIF.

    IF reported IS NOT INITIAL.
      out->write( `Entries in REPORTED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_reported( ) name = `extract_from_reported( )` ).
      out->write( |\n| ).
    ENDIF.

**********************************************************************
*
* Update operations
*
**********************************************************************

    out->write( zcl_demo_abap_aux=>heading( `2) Update operation` ) ).

**********************************************************************
* Notes:
* - The EML request includes a create and an update request. The
*   create request is included to have a %cid to refer to for demo
*   purposes. This instance has not yet been persisted.
* - The EML statement for the create operation includes the ABAP
*   FROM ... (instead of FIELDS ( ... ) WITH ...) for demo purposes.
*   Here, the %control values must be set explicitly.
* - The update request purposely excludes field2 so as not to update
*   the value of this particular field.
**********************************************************************

    MODIFY ENTITIES OF zdemo_abap_rap_ro_m
        ENTITY root
        CREATE FROM VALUE #(
            %control-key_field = if_abap_behv=>mk-on
            %control-field1 = if_abap_behv=>mk-on
            %control-field2 = if_abap_behv=>mk-on
            %control-field3 = if_abap_behv=>mk-on
            %control-field4 = if_abap_behv=>mk-on
          ( %cid = 'cid5'
            key_field = 5
            field1    = 'iii'
            field2    = 'jjj'
            field3    = 50
            field4    = 51 ) )
        UPDATE FIELDS ( field1 field3 field4 )
          WITH VALUE #(
          "Update via cid_ref
          ( %cid_ref = 'cid5'
            field1   = 'up_kkk'
            field2   = 'up_lll' "Value not considered
            field3   = 500
            field4   = 501 )
          "Updates via key
          ( key_field = 1
            field1    = 'up_mmm'
            field3    = 100
            field4    = 101 )
          ( key_field = 2
            field1    = 'up_ooo'
            field3    = 200
            field4    = 201 )
          ( key_field = 99   "Instance to fail
            field1    = 'error'
            field3    = 99
            field4    = 99 ) )
        MAPPED mapped
        FAILED failed
        REPORTED reported.

    COMMIT ENTITIES.

    IF sy-subrc <> 0.
      out->write( `An issue occurred in the RAP save sequence.` ).
    ENDIF.

    "Retrieving and displaying database content
    SELECT FROM zdemo_abap_rapt1
      FIELDS key_field, field1, field2, field3, field4
      ORDER BY key_field
      INTO TABLE @tab_root.

    out->write( data = tab_root name = `tab_root` ).
    out->write( |\n| ).

    "Displaying response information
    IF mapped-root IS NOT INITIAL.
      out->write( `Entries in MAPPED response parameter ` &&
                         `(root entity)` ).
      out->write( |\n| ).
      out->write( data = mapped-root name = `mapped-root` ).
      out->write( |\n| ).
    ENDIF.

    IF failed IS NOT INITIAL.
      out->write( `Entries in FAILED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_failed( ) name = `extract_from_failed( )` ).
      out->write( |\n| ).
    ENDIF.

    IF reported IS NOT INITIAL.
      out->write( `Entries in REPORTED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_reported( ) name = `extract_from_reported( )` ).
      out->write( |\n| ).
    ENDIF.

**********************************************************************
*
* Delete operation
*
**********************************************************************

    out->write( zcl_demo_abap_aux=>heading( `3) Delete operation` ) ).

**********************************************************************
* Notes:
* - The EML request includes a create and an delete request. The
*   create request is included to have a %cid to refer to for demo
*   purposes. This instance has not yet been persisted.
* - EML statements for delete operations can only be used with the
*   ABAP word FROM ....
**********************************************************************

    MODIFY ENTITIES OF zdemo_abap_rap_ro_m
        ENTITY root
        CREATE FIELDS ( key_field field1 field2 field3 field4 )
          WITH VALUE #(
          ( %cid      = 'cid_del'
            key_field = 6
            field1    = 'mmm'
            field2    = 'nnn'
            field3    = 60
            field4    = 61 ) )
        DELETE FROM VALUE #(
          "Deletion via %cid_ref
          ( %cid_ref = 'cid_del' )
          "Deletions via key
          ( key_field = 4 )
          ( key_field = 5 )
          "Instance to fail
          ( key_field = 100 ) )  "Key not available
        MAPPED mapped
        FAILED failed
        REPORTED reported.

    COMMIT ENTITIES.

    IF sy-subrc <> 0.
      out->write( `An issue occurred in the RAP save sequence.` ).
    ENDIF.

    "Retrieving and displaying database content
    SELECT FROM zdemo_abap_rapt1
      FIELDS key_field, field1, field2, field3, field4
      ORDER BY key_field
      INTO TABLE @tab_root.

    out->write( data = tab_root name = `tab_root` ).
    out->write( |\n| ).

    "Displaying response information
    IF mapped-root IS NOT INITIAL.
      out->write( `Entries in MAPPED response parameter ` &&
                         `(root entity)` ).
      out->write( |\n| ).
      out->write( data = mapped-root name = `mapped-root` ).
      out->write( |\n| ).
    ENDIF.

    IF failed IS NOT INITIAL.
      out->write( `Entries in FAILED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_failed( ) name = `extract_from_failed( )` ).
      out->write( |\n| ).
    ENDIF.

    IF reported IS NOT INITIAL.
      out->write( `Entries in REPORTED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_reported( ) name = `extract_from_reported( )` ).
      out->write( |\n| ).
    ENDIF.

**********************************************************************
*
* Action multiply_by_2
*
**********************************************************************

    out->write( zcl_demo_abap_aux=>heading( `4) Action execution: mutliply_by_2` ) ).

**********************************************************************
* Notes:
* - The EML request includes a create request and a request to execute
*   an action. The create request is included to have a %cid to refer
*   to for demo purposes. This instance has not yet been persisted.
* - EML statements for executing actions can only be used with the
*   ABAP word FROM ....
* - As the name implies, the action multiplies field
*   values (field3 and field4) by 2 for requested instances.
**********************************************************************

    MODIFY ENTITIES OF zdemo_abap_rap_ro_m
        ENTITY root
        CREATE FIELDS ( key_field field1 field2 field3 field4 )
          WITH VALUE #(
          ( %cid = 'cid_x2'
            key_field = 7
            field1    = 'ooo'
            field2    = 'ppp'
            field3    = 70
            field4    = 71 ) )
        EXECUTE multiply_by_2 FROM VALUE #(
          "Executing action via %cid_ref
          ( %cid_ref = 'cid_x2' )
          "Executing action via key
          ( key_field  =  1  )
          ( key_field  =  2  )
          ( key_field  =  1234 ) ) "Instance to fail
        MAPPED mapped
        FAILED failed
        REPORTED reported.

    COMMIT ENTITIES.

    IF sy-subrc <> 0.
      out->write( `An issue occurred in the RAP save sequence.` ).
    ENDIF.

    "Retrieving and displaying database content
    SELECT FROM zdemo_abap_rapt1
      FIELDS key_field, field1, field2, field3, field4
      ORDER BY key_field
      INTO TABLE @tab_root.

    out->write( data = tab_root name = `tab_root` ).
    out->write( |\n| ).

    "Displaying response information
    IF mapped-root IS NOT INITIAL.
      out->write( `Entries in MAPPED response parameter ` &&
                         `(root entity)` ).
      out->write( |\n| ).
      out->write( data = mapped-root name = `mapped-root` ).
      out->write( |\n| ).
    ENDIF.

    IF failed IS NOT INITIAL.
      out->write( `Entries in FAILED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_failed( ) name = `extract_from_failed( )` ).
      out->write( |\n| ).
    ENDIF.

    IF reported IS NOT INITIAL.
      out->write( `Entries in REPORTED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_reported( ) name = `extract_from_reported( )` ).
      out->write( |\n| ).
    ENDIF.

**********************************************************************
*
* Create-by-association operation (from root to child entity)
*
**********************************************************************

    out->write( zcl_demo_abap_aux=>heading( `5) Create-by-association operation (from parent to child)` ) ).

**********************************************************************
* Notes:
* - The EML request includes a create and create-by-association
*   request, i. e. a "deep create". An instance is created for the
*   parent entity and, in the same request and based on this
*   instance, instances are created for the child entity, too.
**********************************************************************

    MODIFY ENTITIES OF zdemo_abap_rap_ro_m
        ENTITY root
        CREATE FIELDS ( key_field field1 field2 field3 field4 )
              WITH VALUE #(
              ( %cid      = 'cid_cba'
                key_field = 9
                field1    = 'qqq'
                field2    = 'rrr'
                field3    = 90
                field4    = 91 ) )
        CREATE BY \_child
        FIELDS ( key_ch field_ch1 field_ch2 ) WITH VALUE #(
          "CBA operation via %cid_ref
          ( %cid_ref = 'cid_cba'
            %target = VALUE #( ( %cid      = 'cid_ch1'
                                 key_ch    = 9
                                 field_ch1 = 'aaa_ch'
                                 field_ch2 = 99 )
                               ( %cid      = 'cid_ch2'
                                 key_ch    = 10
                                 field_ch1 = 'bbb_ch'
                                 field_ch2 =  100 ) ) )
          "CBA operation via root key
          ( key_field = 1
            %target = VALUE #( ( %cid      = 'cid_ch3'
                                 key_ch    = 1
                                 field_ch1 = 'ccc_ch'
                                 field_ch2 = 11 )
                               ( %cid      = 'cid_ch4'
                                 key_ch    = 2
                                 field_ch1 = 'ddd_ch'
                                 field_ch2 = 22 ) ) )
          ( key_field = 2
            %target = VALUE #( ( %cid      = 'cid_ch5'
                                 key_ch    = 3
                                 field_ch1 = 'ccc_ch'
                                 field_ch2 = 33 )
                               ( %cid      = 'cid_ch6'
                                 key_ch    = 4
                                 field_ch1 = 'ddd_ch'
                                 field_ch2 = 44 ) ) )
          "Instance to fail
          ( key_field = 123
            %target = VALUE #( ( %cid      = 'cid_ch7'
                                 key_ch    = 1
                                 field_ch1 = 'error'
                                 field_ch2 = 2 )
                               ( %cid      = 'cid_ch8'
                                 key_ch    = 2
                                 field_ch1 = 'error'
                                 field_ch2 = 3 ) ) )
                                 )
          MAPPED mapped
          FAILED failed
          REPORTED reported.

    COMMIT ENTITIES.

    IF sy-subrc <> 0.
      out->write( `An issue occurred in the RAP save sequence.` ).
    ENDIF.

    "Retrieving and displaying database content
    SELECT FROM zdemo_abap_rapt1
      FIELDS key_field, field1, field2, field3, field4
      ORDER BY key_field
      INTO TABLE @tab_root.

    SELECT FROM zdemo_abap_rapt2
      FIELDS key_field, key_ch, field_ch1, field_ch2
      ORDER BY key_field, key_ch
      INTO TABLE @DATA(tab_child).

    out->write( data = tab_root name = `tab_root` ).
    out->write( |\n| ).
    out->write( data = tab_child name = `tab_child` ).
    out->write( |\n| ).

    "Displaying response information
    IF mapped IS NOT INITIAL.
      out->write( `Entries in MAPPED response parameter ` &&
                         `(root and child entity)` ).
      out->write( |\n| ).
      out->write( data = mapped name = `mapped` ).
      out->write( |\n| ).
    ENDIF.

    IF failed IS NOT INITIAL.
      out->write( `Entries in FAILED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_failed( ) name = `extract_from_failed( )` ).
      out->write( |\n| ).
    ENDIF.

    IF reported IS NOT INITIAL.
      out->write( `Entries in REPORTED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_reported( ) name = `extract_from_reported( )` ).
      out->write( |\n| ).
    ENDIF.

**********************************************************************
*
* Validation val
*
**********************************************************************

    out->write( zcl_demo_abap_aux=>heading( `6) Validation val` ) ).

**********************************************************************
* Notes:
* - The EML request includes a create request. The validation's
*   handler method is implementation in a way that the saving of
*   instances is disabled if a field value is not allowed. In this
*   example, the value of the integer in field3 shall not exceed 1000.
*   Here, the third instance will fail for the validation.
*   Consequently, all instances of this request are not saved to the
*   database. Either all is ok and will be saved or nothing.
* - Note that the response information for the validation is only
*   available in the response parameters of the COMMIT ENTITIES
*   statement. Here, the BDEF derived type is
*   ... TYPE RESPONSE FOR ... LATE ....
**********************************************************************

    MODIFY ENTITIES OF zdemo_abap_rap_ro_m
        ENTITY root
        CREATE FIELDS ( key_field field1 field2 field3 field4 )
          WITH VALUE #(
          ( %cid = 'cid_val1'
            key_field = 123
            field1    = 'sss'
            field2    = 'ttt'
            field3    = 1
            field4    = 2 )
          ( %cid = 'cid_val2'
            key_field = 456
            field1    = 'uuu'
            field2    = 'vvv'
            field3    = 3
            field4    = 4 )
          ( %cid = 'cid_val3'
            key_field = 789
            field1    = 'www'
            field2    = 'xxx'
            field3    = 1001
            field4    = 5 ) )
        MAPPED mapped
        FAILED failed
        REPORTED reported.

    COMMIT ENTITIES RESPONSES
      FAILED DATA(failed_late)
      REPORTED DATA(reported_late).

    IF sy-subrc <> 0.
      out->write( `An issue occurred in the RAP save sequence.` ).
    ENDIF.

    "Retrieving and displaying database content
    SELECT FROM zdemo_abap_rapt1
      FIELDS key_field, field1, field2, field3, field4
      ORDER BY key_field
      INTO TABLE @tab_root.

    out->write( data = tab_root name = `tab_root` ).
    out->write( |\n| ).

    "Displaying response information
    IF mapped IS NOT INITIAL.
      out->write( `Entries in MAPPED response parameter ` &&
                         `(root and child entity)` ).
      out->write( |\n| ).
      out->write( data = mapped name = `mapped` ).
      out->write( |\n| ).
    ENDIF.

    IF failed_late IS NOT INITIAL.
      out->write( `Entries in FAILED LATE response parameter` ).
      out->write( |\n| ).
      out->write( data = failed_late name = `failed_late` ).
      out->write( |\n| ).
    ENDIF.

    IF reported_late IS NOT INITIAL.
      out->write( `Entries in REPORTED LATE response parameter` ).
      out->write( |\n| ).
      out->write( data = reported_late name = `reported_late` ).
      out->write( |\n| ).
    ENDIF.

**********************************************************************
*
* Read operation (root entity)
*
**********************************************************************

    out->write( zcl_demo_abap_aux=>heading( `7) Read operation (root entity)` ) ).

**********************************************************************
* Notes:
* - The EML request includes a read request. The EML statement uses
*   the ABAP words ALL FIELDS WITH. In this case, as the name implies,
*   all field values are retrieved. The %control values for all fields
*   are set to if_abap_behv=>mk-on.
* - When using the ABAP words FIELDS ( ... ) WITH and specifying the
*   concrete fields to be read, only for those fields %control is
*   set accordingly.
* - Filling the parameter for RESULT is mandatory.
**********************************************************************

    READ ENTITIES OF zdemo_abap_rap_ro_m
        ENTITY root
        ALL FIELDS WITH VALUE #(
          ( key_field = 1 )
          ( key_field = 2 )
          ( key_field = 7 )
          ( key_field = 5 ) ) "Instance to fail
        RESULT DATA(result)
        FAILED failed
        REPORTED reported.

    "Displaying the read result
    out->write( data = result name = `result` ).
    out->write( |\n| ).

    "Displaying response information
    IF failed IS NOT INITIAL.
      out->write( `Entries in FAILED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_failed( ) name = `extract_from_failed( )` ).
      out->write( |\n| ).
    ENDIF.
    IF reported IS NOT INITIAL.
      out->write( `Entries in REPORTED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_reported( ) name = `extract_from_reported( )` ).
      out->write( |\n| ).
    ENDIF.

*********************************************************************
*
* Read operation (child entity)
*
**********************************************************************

    out->write( zcl_demo_abap_aux=>heading( `8) Read operation (child entity)` ) ).

**********************************************************************
* Notes:
* - The EML request includes a read request. The read operation is
*   executed on the child entity directly by specifying the alias, as
*   it is defined in the BDEF, following the ABAP word ENTITY.
* - All field values are read using the addition ALL FIELDS WITH.
**********************************************************************

    READ ENTITIES OF zdemo_abap_rap_ro_m
          ENTITY child
          ALL FIELDS WITH VALUE #(
            ( key_field = 1 key_ch = 1 )
            ( key_field = 2 key_ch = 4 )
            "Instances to fail
            ( key_field = 9 )
            ( key_field = 9 key_ch = 11 ) )
          RESULT DATA(read_ch)
          FAILED failed
          REPORTED reported.

    "Displaying read result
    out->write( data = read_ch name = `read_ch` ).
    out->write( |\n| ).


    "Displaying response information
    IF failed IS NOT INITIAL.
      out->write( `Entries in FAILED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_failed( ) name = `extract_from_failed( )` ).
      out->write( |\n| ).
    ENDIF.
    IF reported IS NOT INITIAL.
      out->write( `Entries in REPORTED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_reported( ) name = `extract_from_reported( )` ).
      out->write( |\n| ).
    ENDIF.

**********************************************************************
*
* Read-by-association operation (from parent to child)
*
**********************************************************************

    out->write( zcl_demo_abap_aux=>heading( `9) Read-by-association operation (from parent to child)` ) ).

**********************************************************************
* Notes:
* - The EML request includes a read-by-association request from the
*   parent to the child.
* - All field values are read using the addition ALL FIELDS WITH.
* - Specifying the parameter for RESULT is mandatory.
* - Additionally, the optional association links are retrieved.
**********************************************************************

    READ ENTITIES OF zdemo_abap_rap_ro_m
          ENTITY root
          BY \_child
          ALL FIELDS WITH VALUE #(
            ( key_field = 2 )
            ( key_field = 9 )
            ( key_field = 999 ) ) "Instance to fail
          RESULT DATA(rba_result)
          LINK DATA(association_links)
          FAILED failed
          REPORTED reported.

    "Displaying read result and association links
    out->write( data = rba_result name = `rba_result` ).
    out->write( |\n| ).
    out->write( data = association_links name = `association_links` ).
    out->write( |\n| ).

    "Displaying response information
    IF failed IS NOT INITIAL.
      out->write( `Entries in FAILED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_failed( ) name = `extract_from_failed( )` ).
      out->write( |\n| ).
    ENDIF.
    IF reported IS NOT INITIAL.
      out->write( `Entries in REPORTED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_reported( ) name = `extract_from_reported( )` ).
      out->write( |\n| ).
    ENDIF.

**********************************************************************
*
* Read-by-association operation (from child to parent)
*
**********************************************************************

    out->write( zcl_demo_abap_aux=>heading( `10) Read-by-association operation (from child to parent)` ) ).

**********************************************************************
* Notes:
* - The EML request includes a read-by-association request from the
*   child to the parent.
* - All field values are read using the addition ALL FIELDS WITH.
* - Specifying the parameter for RESULT is mandatory.
* - Additionally, the optional association links are retrieved.
**********************************************************************

    READ ENTITIES OF zdemo_abap_rap_ro_m
      ENTITY child
      BY \_parent ALL FIELDS WITH VALUE #(
         ( key_field = 1 key_ch = 1 )
         ( key_field = 2 key_ch = 4 )
         "Instances to fail
         ( key_field = 1 key_ch = 3 )
         ( key_field = 543 key_ch = 1 ) )
       RESULT DATA(rba_parent)
       LINK DATA(association_links_parent)
       FAILED failed
       REPORTED reported.

    "Displaying read result and association links
    out->write( data = rba_parent name = `rba_parent` ).
    out->write( |\n| ).
    out->write( data = association_links_parent name = `association_links_parent` ).
    out->write( |\n| ).

    "Displaying response information
    IF failed IS NOT INITIAL.
      out->write( `Entries in FAILED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_failed( ) name = `extract_from_failed( )` ).
      out->write( |\n| ).
    ENDIF.
    IF reported IS NOT INITIAL.
      out->write( `Entries in REPORTED response parameter` ).
      out->write( |\n| ).
      out->write( data = extract_from_reported( ) name = `extract_from_reported( )` ).
      out->write( |\n| ).
    ENDIF.

**********************************************************************
*
* Excursion: Read and read-by-association operation using a dynamic
* EML statement
*
**********************************************************************

    out->write( zcl_demo_abap_aux=>heading( `11) Excursion: Read and read-by-association ` &&
                     `operations using dynamic EML` ) ).
    DATA:
      op_tab          TYPE abp_behv_retrievals_tab,
      read_dyn        TYPE TABLE FOR READ IMPORT zdemo_abap_rap_ro_m,
      read_dyn_result TYPE TABLE FOR READ RESULT zdemo_abap_rap_ro_m,
      rba_dyn         TYPE TABLE FOR READ IMPORT
                        zdemo_abap_rap_ro_m\_child,
      rba_dyn_result  TYPE TABLE FOR READ RESULT
                        zdemo_abap_rap_ro_m\_child,
      rba_dyn_link    TYPE TABLE FOR READ LINK zdemo_abap_rap_ro_m\_child.

    read_dyn = VALUE #(
      ( %key-key_field = 1
        %control = VALUE #(
          field1 = if_abap_behv=>mk-on
          field2 = if_abap_behv=>mk-on
          field3 = if_abap_behv=>mk-on
          field4 = if_abap_behv=>mk-on ) )
      ( %key-key_field = 2
        %control = VALUE #(
          field1 = if_abap_behv=>mk-on
          field2 = if_abap_behv=>mk-on
          field3 = if_abap_behv=>mk-on
          field4 = if_abap_behv=>mk-on ) ) ).

    rba_dyn = VALUE #(
     ( %key-key_field = 1
       %control = VALUE #(
          key_ch    = if_abap_behv=>mk-on
          field_ch1 = if_abap_behv=>mk-on
          field_ch2 = if_abap_behv=>mk-on ) )
      ( %key-key_field = 2
        %control = VALUE #(
          key_ch    = if_abap_behv=>mk-on
          field_ch1 = if_abap_behv=>mk-on
          field_ch2 = if_abap_behv=>mk-on ) ) ).

    op_tab = VALUE #(
       ( op = if_abap_behv=>op-r-read
         entity_name = 'ZDEMO_ABAP_RAP_RO_M'
         instances   = REF #( read_dyn )
         results     = REF #( read_dyn_result ) )
       ( op = if_abap_behv=>op-r-read_ba
         entity_name = 'ZDEMO_ABAP_RAP_RO_M'
         sub_name    = '_CHILD'
         full        = abap_true
         instances   = REF #( rba_dyn )
         results     = REF #( rba_dyn_result )
         links       = REF #( rba_dyn_link ) ) ).

    READ ENTITIES OPERATIONS op_tab.

    out->write( `Read result (root)` ).
    out->write( |\n| ).
    out->write( data = read_dyn_result name = `read_dyn_result` ).
    out->write( |\n| ).
    out->write( `Read result (read-by-association)` ).
    out->write( |\n| ).
    out->write( data = rba_dyn_result name = `rba_dyn_result` ).
    out->write( |\n| ).
    out->write( `Links` ).
    out->write( |\n| ).
    out->write( data = rba_dyn_link name = `rba_dyn_link` ).
  ENDMETHOD.

  METHOD initialize_dbtabs.
    DELETE FROM zdemo_abap_rapt1.
    DELETE FROM zdemo_abap_rapt2.
  ENDMETHOD.
ENDCLASS.