Barcode und QR-Code Generierung in ABAP Cloud

kategorie

ABAP Cloud

Veröffentlicht

Feb 14, 2026

autor

Barcodes und QR-Codes sind aus modernen Geschaeftsprozessen nicht mehr wegzudenken. Sie beschleunigen die Datenerfassung, reduzieren Fehler und ermoeglichen eine lueckenlose Rueckverfolgbarkeit. In ABAP Cloud gibt es verschiedene Ansaetze, diese Codes zu generieren – von ABAP-nativen Loesungen bis hin zu externen Cloud-Services.

Barcode-Typen im Ueberblick

Je nach Anwendungsfall kommen unterschiedliche Barcode-Formate zum Einsatz:

Barcode-Typ	Datenkapazitaet	Anwendungsbereich
Code128	Alphanumerisch, variabel	Logistik, Versand, interne Kennzeichnung
EAN-13	13 Ziffern	Einzelhandel, Konsumgueter
EAN-8	8 Ziffern	Kleine Verpackungen
Code39	Alphanumerisch	Industrie, Automotive
QR-Code	Bis 4.296 Zeichen	URLs, Kontaktdaten, Rechnungen
DataMatrix	Bis 2.335 Zeichen	Pharma, Elektronik, kleine Bauteile

1D vs. 2D Codes

┌─────────────────────────────────────────────────────────────────────┐
│                    Barcode-Klassifikation                           │
│                                                                     │
│  ┌────────────────────────────┐  ┌────────────────────────────┐   │
│  │      1D-Barcodes           │  │      2D-Codes              │   │
│  │                            │  │                            │   │
│  │  ║║█║║█║║║█║█║║█║║        │  │  ▓▓▓▓▓▓▓ ▓▓▓ ▓▓▓▓▓▓▓      │   │
│  │  Code128, EAN, Code39      │  │  ▓     ▓ ▓▓▓ ▓     ▓      │   │
│  │                            │  │  ▓ ▓▓▓ ▓ ▓▓  ▓ ▓▓▓ ▓      │   │
│  │  - Linear                  │  │  ▓ ▓▓▓ ▓  ▓▓ ▓ ▓▓▓ ▓      │   │
│  │  - Nur horizontale Info    │  │  ▓     ▓ ▓ ▓ ▓     ▓      │   │
│  │  - Scanner/Lesegeraet      │  │  ▓▓▓▓▓▓▓ ▓ ▓ ▓▓▓▓▓▓▓      │   │
│  │                            │  │  QR-Code, DataMatrix       │   │
│  │                            │  │                            │   │
│  │                            │  │  - Matrix-basiert          │   │
│  │                            │  │  - Hohe Datenkapazitaet    │   │
│  │                            │  │  - Kamera/Smartphone       │   │
│  └────────────────────────────┘  └────────────────────────────┘   │
└─────────────────────────────────────────────────────────────────────┘

Generierungsoptionen in ABAP Cloud

In ABAP Cloud stehen dir mehrere Wege zur Barcode-Generierung zur Verfuegung:

Option	Beschreibung	Vorteile	Nachteile
Externe REST-APIs	Cloud-basierte Barcode-Services	Flexibel, viele Formate	Netzwerkabhaengig, Kosten
ABAP-native Generierung	Algorithmus in ABAP implementiert	Keine Abhaengigkeiten	Aufwaendig, limitierte Formate
SAP Forms Service	Barcodes in PDF-Templates	Integriert	Nur fuer PDFs
JavaScript in Fiori	Frontend-Generierung	Schnell, offline	Nur UI-Anzeige

QR-Code Generierung mit externem Service

Die einfachste und flexibelste Methode ist die Nutzung eines externen QR-Code-Services:

HTTP-Client fuer QR-Code API

CLASS zcl_qr_code_generator DEFINITION
  PUBLIC
  FINAL
  CREATE PUBLIC.

  PUBLIC SECTION.
    TYPES: BEGIN OF ty_qr_result,
             image_base64 TYPE string,
             content_type TYPE string,
             success      TYPE abap_bool,
             message      TYPE string,
           END OF ty_qr_result.

    METHODS generate_qr_code
      IMPORTING
        iv_content    TYPE string
        iv_size       TYPE i DEFAULT 200
        iv_format     TYPE string DEFAULT 'PNG'
      RETURNING
        VALUE(rs_result) TYPE ty_qr_result.

  PRIVATE SECTION.
    METHODS get_http_client
      RETURNING
        VALUE(ro_client) TYPE REF TO if_web_http_client.

ENDCLASS.

CLASS zcl_qr_code_generator IMPLEMENTATION.

  METHOD generate_qr_code.
    DATA: lo_client   TYPE REF TO if_web_http_client,
          lo_response TYPE REF TO if_web_http_response,
          lv_url      TYPE string.

    TRY.
        " URL mit Parametern aufbauen
        " Beispiel mit goqr.me API (kostenlos)
        lv_url = |https://api.qrserver.com/v1/create-qr-code/| &&
                 |?data={ cl_web_utility=>escape_url( iv_content ) }| &&
                 |&size={ iv_size }x{ iv_size }| &&
                 |&format={ iv_format }|.

        " HTTP-Client erstellen
        lo_client = cl_web_http_client_manager=>create_by_http_destination(
          i_destination = cl_http_destination_provider=>create_by_url( lv_url )
        ).

        " Request senden
        lo_response = lo_client->execute( if_web_http_client=>get ).

        " Antwort auswerten
        IF lo_response->get_status( )-code = 200.
          rs_result-image_base64 = cl_web_utility=>encode_base64(
            lo_response->get_binary( )
          ).
          rs_result-content_type = |image/{ to_lower( iv_format ) }|.
          rs_result-success = abap_true.
        ELSE.
          rs_result-success = abap_false.
          rs_result-message = |HTTP Error: { lo_response->get_status( )-code }|.
        ENDIF.

        lo_client->close( ).

      CATCH cx_web_http_client_error INTO DATA(lx_http).
        rs_result-success = abap_false.
        rs_result-message = lx_http->get_text( ).
      CATCH cx_root INTO DATA(lx_error).
        rs_result-success = abap_false.
        rs_result-message = lx_error->get_text( ).
    ENDTRY.
  ENDMETHOD.

  METHOD get_http_client.
    " Alternative: Destination aus Communication Arrangement nutzen
    ro_client = cl_web_http_client_manager=>create_by_http_destination(
      i_destination = cl_http_destination_provider=>create_by_comm_arrangement(
        comm_scenario  = 'Z_QR_CODE_SERVICE'
        service_id     = 'Z_QR_CODE_OUTBOUND'
      )
    ).
  ENDMETHOD.

ENDCLASS.

Communication Arrangement einrichten

Fuer produktive Systeme solltest du eine Destination verwenden:

1. Communication System anlegen (SAP BTP Cockpit)
   - Name: QR_CODE_SERVICE
   - Host: api.qrserver.com
   - Port: 443
   - Protocol: HTTPS

2. Communication Arrangement erstellen
   - Scenario: Z_QR_CODE_SERVICE
   - Outbound Service: Z_QR_CODE_OUTBOUND
   - Authentication: None (oeffentliche API)

3. Outbound Service Definition (ABAP)

" Service Consumption Model (ABAP)
@EndUserText.label: 'QR Code Service'
define service ZS_QR_CODE_SERVICE {
  expose zcl_qr_code_generator as QRCodeGenerator;
}

Barcode Generierung (Code128)

Code128 ist ein weit verbreiteter 1D-Barcode fuer Logistik und Versand:

Algorithmus fuer Code128

CLASS zcl_code128_generator DEFINITION
  PUBLIC
  FINAL
  CREATE PUBLIC.

  PUBLIC SECTION.
    TYPES: BEGIN OF ty_barcode_result,
             barcode_string TYPE string,
             check_digit    TYPE i,
             success        TYPE abap_bool,
             message        TYPE string,
           END OF ty_barcode_result.

    METHODS generate_code128b
      IMPORTING
        iv_data          TYPE string
      RETURNING
        VALUE(rs_result) TYPE ty_barcode_result.

    METHODS generate_barcode_image
      IMPORTING
        iv_data          TYPE string
        iv_width         TYPE i DEFAULT 300
        iv_height        TYPE i DEFAULT 100
      RETURNING
        VALUE(rv_base64) TYPE string.

  PRIVATE SECTION.
    CONSTANTS: BEGIN OF gc_code128b,
                 start_code TYPE i VALUE 104,
                 stop_code  TYPE i VALUE 106,
               END OF gc_code128b.

    CLASS-DATA: gt_code128_patterns TYPE STANDARD TABLE OF string WITH EMPTY KEY.

    CLASS-METHODS class_constructor.

    METHODS calculate_check_digit
      IMPORTING
        iv_data            TYPE string
      RETURNING
        VALUE(rv_checksum) TYPE i.

ENDCLASS.

CLASS zcl_code128_generator IMPLEMENTATION.

  METHOD class_constructor.
    " Code128 Barcode-Muster initialisieren
    " Jedes Muster besteht aus 6 Balken/Luecken
    gt_code128_patterns = VALUE #(
      ( |11011001100| )  " 0
      ( |11001101100| )  " 1
      ( |11001100110| )  " 2
      " ... weitere Muster
    ).
  ENDMETHOD.

  METHOD generate_code128b.
    DATA: lv_checksum TYPE i,
          lv_index    TYPE i.

    " Validierung
    IF strlen( iv_data ) = 0.
      rs_result-success = abap_false.
      rs_result-message = 'Keine Daten angegeben'.
      RETURN.
    ENDIF.

    " Pruefsumme berechnen
    lv_checksum = calculate_check_digit( iv_data ).

    rs_result-check_digit = lv_checksum.
    rs_result-success = abap_true.

    " Barcode-String zusammenbauen (vereinfacht)
    rs_result-barcode_string = |{ gc_code128b-start_code }|.

    DO strlen( iv_data ) TIMES.
      lv_index = sy-index - 1.
      rs_result-barcode_string = rs_result-barcode_string &&
        cl_abap_conv_codepage=>convert_to(
          source = substring( val = iv_data off = lv_index len = 1 )
        ).
    ENDDO.

    rs_result-barcode_string = rs_result-barcode_string &&
      |{ lv_checksum }{ gc_code128b-stop_code }|.
  ENDMETHOD.

  METHOD calculate_check_digit.
    DATA: lv_sum   TYPE i,
          lv_char  TYPE c LENGTH 1,
          lv_value TYPE i.

    " Start mit Start-Code
    lv_sum = gc_code128b-start_code.

    " Jeden Buchstaben gewichtet addieren
    DO strlen( iv_data ) TIMES.
      lv_char = iv_data+( sy-index - 1 )(1).

      " ASCII-Wert - 32 ergibt Code128B-Wert
      lv_value = cl_abap_conv_codepage=>convert_to(
        source = CONV string( lv_char )
      )-1 - 32.

      lv_sum = lv_sum + ( lv_value * sy-index ).
    ENDDO.

    " Modulo 103
    rv_checksum = lv_sum MOD 103.
  ENDMETHOD.

  METHOD generate_barcode_image.
    " Fuer Bildgenerierung externen Service nutzen
    DATA(lo_qr_gen) = NEW zcl_qr_code_generator( ).

    " Barcode-Service URL (Beispiel mit barcodeapi.org)
    DATA(lv_url) = |https://barcodeapi.org/api/128/{ cl_web_utility=>escape_url( iv_data ) }|.

    TRY.
        DATA(lo_client) = cl_web_http_client_manager=>create_by_http_destination(
          i_destination = cl_http_destination_provider=>create_by_url( lv_url )
        ).

        DATA(lo_response) = lo_client->execute( if_web_http_client=>get ).

        IF lo_response->get_status( )-code = 200.
          rv_base64 = cl_web_utility=>encode_base64(
            lo_response->get_binary( )
          ).
        ENDIF.

        lo_client->close( ).

      CATCH cx_root.
        CLEAR rv_base64.
    ENDTRY.
  ENDMETHOD.

ENDCLASS.

Integration in PDF-Dokumente

Barcodes werden haeufig in PDFs wie Lieferscheinen oder Rechnungen benoetigt:

XSL-FO Template mit eingebettetem Barcode

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:fo="http://www.w3.org/1999/XSL/Format">

  <xsl:template match="/">
    <fo:root>
      <fo:layout-master-set>
        <fo:simple-page-master master-name="delivery-note"
          page-height="297mm" page-width="210mm"
          margin-top="20mm" margin-bottom="20mm"
          margin-left="20mm" margin-right="20mm">
          <fo:region-body/>
        </fo:simple-page-master>
      </fo:layout-master-set>

      <fo:page-sequence master-reference="delivery-note">
        <fo:flow flow-name="xsl-region-body">

          <!-- Kopfbereich mit Barcode -->
          <fo:block-container position="absolute" top="0mm" right="0mm">
            <fo:block>
              <!-- Barcode als Base64-Bild -->
              <fo:external-graphic
                src="url('data:image/png;base64,{/document/barcode_image}')"
                content-height="15mm"
                scaling="uniform"/>
            </fo:block>
            <fo:block font-size="8pt" text-align="center">
              <xsl:value-of select="/document/delivery_number"/>
            </fo:block>
          </fo:block-container>

          <!-- QR-Code fuer Tracking-URL -->
          <fo:block-container position="absolute" top="50mm" right="0mm">
            <fo:block>
              <fo:external-graphic
                src="url('data:image/png;base64,{/document/qr_code_image}')"
                content-height="25mm"
                scaling="uniform"/>
            </fo:block>
            <fo:block font-size="7pt" text-align="center">
              Scan fuer Tracking
            </fo:block>
          </fo:block-container>

          <!-- Dokumentinhalt -->
          <fo:block font-size="18pt" font-weight="bold" margin-bottom="10mm">
            Lieferschein
          </fo:block>

          <!-- Weitere Inhalte... -->

        </fo:flow>
      </fo:page-sequence>
    </fo:root>
  </xsl:stylesheet>

PDF-Generierung mit Barcode

CLASS zcl_delivery_note_pdf DEFINITION
  PUBLIC
  FINAL
  CREATE PUBLIC.

  PUBLIC SECTION.
    METHODS generate_delivery_note
      IMPORTING
        is_delivery      TYPE zdelivery_data
      RETURNING
        VALUE(rv_pdf)    TYPE xstring
      RAISING
        cx_transformation_error.

  PRIVATE SECTION.
    METHODS prepare_xml_data
      IMPORTING
        is_delivery     TYPE zdelivery_data
      RETURNING
        VALUE(rv_xml)   TYPE string.

    METHODS add_barcode_images
      IMPORTING
        is_delivery     TYPE zdelivery_data
      EXPORTING
        ev_barcode_b64  TYPE string
        ev_qrcode_b64   TYPE string.

ENDCLASS.

CLASS zcl_delivery_note_pdf IMPLEMENTATION.

  METHOD generate_delivery_note.
    DATA: lv_xml         TYPE string,
          lv_barcode_b64 TYPE string,
          lv_qrcode_b64  TYPE string,
          lv_xslfo       TYPE string,
          lv_pdf         TYPE xstring.

    " Barcodes generieren
    add_barcode_images(
      EXPORTING
        is_delivery    = is_delivery
      IMPORTING
        ev_barcode_b64 = lv_barcode_b64
        ev_qrcode_b64  = lv_qrcode_b64
    ).

    " XML-Daten vorbereiten
    lv_xml = prepare_xml_data( is_delivery ).

    " Barcode-Bilder in XML einsetzen
    REPLACE ALL OCCURRENCES OF '{BARCODE_IMAGE}' IN lv_xml
      WITH lv_barcode_b64.
    REPLACE ALL OCCURRENCES OF '{QRCODE_IMAGE}' IN lv_xml
      WITH lv_qrcode_b64.

    " XSL-FO Transformation
    CALL TRANSFORMATION z_delivery_note_xslfo
      SOURCE XML lv_xml
      RESULT XML lv_xslfo.

    " XSL-FO zu PDF konvertieren
    " (erfordert FOP-Service oder externen PDF-Renderer)
    rv_pdf = zcl_pdf_renderer=>render_xslfo( lv_xslfo ).
  ENDMETHOD.

  METHOD add_barcode_images.
    DATA(lo_barcode_gen) = NEW zcl_code128_generator( ).
    DATA(lo_qr_gen) = NEW zcl_qr_code_generator( ).

    " Code128 Barcode fuer Lieferscheinnummer
    ev_barcode_b64 = lo_barcode_gen->generate_barcode_image(
      iv_data   = is_delivery-delivery_number
      iv_width  = 300
      iv_height = 80
    ).

    " QR-Code mit Tracking-URL
    DATA(lv_tracking_url) = |https://tracking.example.com/{ is_delivery-delivery_number }|.

    DATA(ls_qr_result) = lo_qr_gen->generate_qr_code(
      iv_content = lv_tracking_url
      iv_size    = 200
    ).

    IF ls_qr_result-success = abap_true.
      ev_qrcode_b64 = ls_qr_result-image_base64.
    ENDIF.
  ENDMETHOD.

  METHOD prepare_xml_data.
    " XML-Struktur fuer das PDF aufbauen
    rv_xml = |<?xml version="1.0" encoding="UTF-8"?>| &&
             |<document>| &&
             |  <delivery_number>{ is_delivery-delivery_number }</delivery_number>| &&
             |  <customer_name>{ is_delivery-customer_name }</customer_name>| &&
             |  <barcode_image>{BARCODE_IMAGE}</barcode_image>| &&
             |  <qr_code_image>{QRCODE_IMAGE}</qr_code_image>| &&
             |  <items>|.

    LOOP AT is_delivery-items INTO DATA(ls_item).
      rv_xml = rv_xml &&
        |    <item>| &&
        |      <material>{ ls_item-material }</material>| &&
        |      <quantity>{ ls_item-quantity }</quantity>| &&
        |    </item>|.
    ENDLOOP.

    rv_xml = rv_xml &&
             |  </items>| &&
             |</document>|.
  ENDMETHOD.

ENDCLASS.

Anzeige in Fiori App

Fuer die Anzeige von Barcodes in Fiori Apps gibt es zwei Ansaetze:

Backend-generierte Bilder

Der Barcode wird im Backend generiert und als Base64-String zum Frontend gesendet:

" RAP Action fuer Barcode-Generierung
managed implementation in class zbp_i_product unique;
strict ( 2 );

define behavior for ZI_Product alias Product
{
  // Action zum Generieren des Produkt-Barcodes
  action generateBarcode result [1] $self;

  // Virtuelles Feld fuer Barcode-Bild
  field ( readonly ) BarcodeImage;
}

CLASS zbp_i_product DEFINITION LOCAL.
  PRIVATE SECTION.
    METHODS generateBarcode FOR MODIFY
      IMPORTING keys FOR ACTION Product~generateBarcode RESULT result.
ENDCLASS.

CLASS zbp_i_product IMPLEMENTATION.

  METHOD generateBarcode.
    " Produkte lesen
    READ ENTITIES OF zi_product IN LOCAL MODE
      ENTITY Product
        FIELDS ( ProductId ProductName )
        WITH CORRESPONDING #( keys )
      RESULT DATA(lt_products).

    LOOP AT lt_products ASSIGNING FIELD-SYMBOL(<ls_product>).
      " Barcode generieren
      DATA(lo_barcode) = NEW zcl_code128_generator( ).
      DATA(lv_barcode_b64) = lo_barcode->generate_barcode_image(
        iv_data = CONV string( <ls_product>-ProductId )
      ).

      " Produkt mit Barcode-Bild aktualisieren
      MODIFY ENTITIES OF zi_product IN LOCAL MODE
        ENTITY Product
          UPDATE FIELDS ( BarcodeImage )
          WITH VALUE #( (
            %tky = <ls_product>-%tky
            BarcodeImage = lv_barcode_b64
          ) ).
    ENDLOOP.

    " Ergebnis zurueckgeben
    READ ENTITIES OF zi_product IN LOCAL MODE
      ENTITY Product
        ALL FIELDS
        WITH CORRESPONDING #( keys )
      RESULT DATA(lt_result).

    result = VALUE #( FOR ls_prod IN lt_result (
      %tky = ls_prod-%tky
      %param = ls_prod
    ) ).
  ENDMETHOD.

ENDCLASS.

CDS View mit Barcode-Feld

@EndUserText.label: 'Produkt mit Barcode'
@Metadata.allowExtensions: true
define view entity ZC_Product
  as projection on ZI_Product
{
      @UI: {
        lineItem: [{ position: 10 }],
        identification: [{ position: 10 }]
      }
  key ProductId,

      @UI: {
        lineItem: [{ position: 20 }],
        identification: [{ position: 20 }]
      }
      ProductName,

      @UI: {
        identification: [{
          position: 30,
          label: 'Barcode'
        }]
      }
      @UI.dataPoint: {
        visualization: #STANDARD
      }
      @Semantics.imageUrl: true
      BarcodeImageUrl,

      @UI.hidden: true
      BarcodeImage
}

Berechnung der Barcode-URL

define view entity ZI_Product
  as select from zproduct
{
  key product_id    as ProductId,
      product_name  as ProductName,

      -- URL fuer Barcode-API
      concat(
        'https://barcodeapi.org/api/128/',
        product_id
      ) as BarcodeImageUrl,

      -- Placeholder fuer generiertes Bild
      cast( '' as abap.string ) as BarcodeImage
}

Externe Services vs. ABAP-native Loesungen

Vergleich der Ansaetze

Kriterium	Externe Services	ABAP-native
Setup-Aufwand	Gering	Hoch
Unterstuetzte Formate	Viele	Begrenzt
Performance	Netzwerklatenz	Schnell
Offline-Faehigkeit	Nein	Ja
Kosten	Ggf. API-Kosten	Keine
Wartung	Beim Anbieter	Eigenverantwortlich

Empfehlung nach Anwendungsfall

┌─────────────────────────────────────────────────────────────────────┐
│                   Entscheidungsbaum                                 │
│                                                                     │
│  Benoetigst du viele Barcode-Formate?                              │
│  │                                                                  │
│  ├── Ja ──► Externer Service (z.B. barcodeapi.org)                │
│  │                                                                  │
│  └── Nein                                                          │
│      │                                                             │
│      └── Ist Offline-Faehigkeit wichtig?                          │
│          │                                                         │
│          ├── Ja ──► ABAP-native Implementierung                   │
│          │                                                         │
│          └── Nein                                                  │
│              │                                                     │
│              └── Hohe Volumina (>1000/Minute)?                    │
│                  │                                                 │
│                  ├── Ja ──► ABAP-native oder Self-hosted         │
│                  │                                                 │
│                  └── Nein ──► Externer Service                    │
└─────────────────────────────────────────────────────────────────────┘

Beliebte externe Barcode-APIs

Service	URL	Kostenmodell
goQR.me	api.qrserver.com	Kostenlos
Barcode API	barcodeapi.org	Kostenlos
Zxing	zxing.org	Open Source
QRCode Monkey	qrcode-monkey.com	Freemium

Best Practices

Performance-Optimierung

" Barcode-Generierung cachen
CLASS zcl_barcode_cache DEFINITION
  PUBLIC
  FINAL
  CREATE PRIVATE.

  PUBLIC SECTION.
    CLASS-METHODS get_instance
      RETURNING
        VALUE(ro_instance) TYPE REF TO zcl_barcode_cache.

    METHODS get_barcode
      IMPORTING
        iv_content       TYPE string
        iv_type          TYPE string DEFAULT 'QR'
      RETURNING
        VALUE(rv_base64) TYPE string.

  PRIVATE SECTION.
    CLASS-DATA: go_instance TYPE REF TO zcl_barcode_cache.

    TYPES: BEGIN OF ty_cache_entry,
             content  TYPE string,
             type     TYPE string,
             image    TYPE string,
             created  TYPE timestamp,
           END OF ty_cache_entry.

    DATA: mt_cache TYPE HASHED TABLE OF ty_cache_entry
                   WITH UNIQUE KEY content type.

    CONSTANTS: gc_cache_ttl_sec TYPE i VALUE 3600.  " 1 Stunde

ENDCLASS.

CLASS zcl_barcode_cache IMPLEMENTATION.

  METHOD get_instance.
    IF go_instance IS NOT BOUND.
      go_instance = NEW #( ).
    ENDIF.
    ro_instance = go_instance.
  ENDMETHOD.

  METHOD get_barcode.
    DATA: ls_cache TYPE ty_cache_entry,
          lv_now   TYPE timestamp.

    GET TIME STAMP FIELD lv_now.

    " Im Cache suchen
    READ TABLE mt_cache INTO ls_cache
      WITH KEY content = iv_content
               type    = iv_type.

    IF sy-subrc = 0.
      " Pruefen ob noch gueltig
      IF lv_now - ls_cache-created < gc_cache_ttl_sec.
        rv_base64 = ls_cache-image.
        RETURN.
      ELSE.
        " Abgelaufen - aus Cache entfernen
        DELETE mt_cache WHERE content = iv_content AND type = iv_type.
      ENDIF.
    ENDIF.

    " Neu generieren
    CASE iv_type.
      WHEN 'QR'.
        DATA(lo_qr) = NEW zcl_qr_code_generator( ).
        DATA(ls_result) = lo_qr->generate_qr_code( iv_content ).
        IF ls_result-success = abap_true.
          rv_base64 = ls_result-image_base64.
        ENDIF.

      WHEN 'CODE128'.
        DATA(lo_barcode) = NEW zcl_code128_generator( ).
        rv_base64 = lo_barcode->generate_barcode_image( iv_content ).
    ENDCASE.

    " In Cache speichern
    IF rv_base64 IS NOT INITIAL.
      INSERT VALUE #(
        content = iv_content
        type    = iv_type
        image   = rv_base64
        created = lv_now
      ) INTO TABLE mt_cache.
    ENDIF.
  ENDMETHOD.

ENDCLASS.

Fehlerbehandlung

" Robuste Barcode-Generierung mit Fallback
METHODS generate_with_fallback
  IMPORTING
    iv_content       TYPE string
  RETURNING
    VALUE(rv_base64) TYPE string.

METHOD generate_with_fallback.
  " Primaerer Service versuchen
  TRY.
      DATA(lo_qr) = NEW zcl_qr_code_generator( ).
      DATA(ls_result) = lo_qr->generate_qr_code( iv_content ).

      IF ls_result-success = abap_true.
        rv_base64 = ls_result-image_base64.
        RETURN.
      ENDIF.

    CATCH cx_root INTO DATA(lx_error).
      " Fehler loggen
      zcl_logger=>log_error(
        iv_message = |QR-Generierung fehlgeschlagen: { lx_error->get_text( ) }|
      ).
  ENDTRY.

  " Fallback: Alternativer Service
  TRY.
      rv_base64 = zcl_barcode_fallback=>generate( iv_content ).
    CATCH cx_root.
      " Letzter Fallback: Platzhalter-Bild
      rv_base64 = zcl_barcode_fallback=>get_placeholder( ).
  ENDTRY.
ENDMETHOD.

Zusammenfassung

Aspekt	Empfehlung
QR-Codes	Externe API (goQR.me) fuer einfache Integration
1D-Barcodes	Externe API oder ABAP-native fuer Code128
PDF-Integration	Base64-kodierte Bilder in XSL-FO
Fiori-Anzeige	Backend-Generierung mit @Semantics.imageUrl
Performance	Caching bei wiederholten Aufrufen
Fehlertoleranz	Fallback-Mechanismen implementieren

Die Wahl zwischen externen Services und ABAP-nativen Loesungen haengt von deinen Anforderungen ab. Fuer die meisten Anwendungsfaelle bieten externe APIs die beste Balance aus Funktionalitaet und Implementierungsaufwand.