Properly supports barcodes for GTIN-14 using the ITF format

src/main/java/sirius/web/templates/pdf/ImageReplacedElementFactory.java

@@ -26,7 +26,7 @@
 import java.util.Optional;
 
 /**
- * Used by the XHTMLRenderer (creating PDFs) to replace img elements by their references image.
+ * Used by the XHTMLRenderer (creating PDFs) to replace img elements by their referenced image.
  * <p>
  * Alongside http different URI protocols are supported. These are handled by classes extending
  * {@link PdfReplaceHandler}.

src/main/java/sirius/web/templates/pdf/handlers/BarcodePdfReplaceHandler.java

@@ -8,17 +8,13 @@
 
 package sirius.web.templates.pdf.handlers;
 
-import com.lowagie.text.pdf.Barcode;
-import com.lowagie.text.pdf.Barcode128;
-import com.lowagie.text.pdf.BarcodeEAN;
-import com.lowagie.text.pdf.BarcodeInter25;
 import org.xhtmlrenderer.extend.FSImage;
 import org.xhtmlrenderer.extend.UserAgentCallback;
 import org.xhtmlrenderer.pdf.ITextFSImage;
 import sirius.kernel.commons.Strings;
 import sirius.kernel.di.std.Register;
+import sirius.web.util.BarcodeController;
 
-import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import java.awt.Color;
 import java.awt.Image;
@@ -33,11 +29,6 @@
 @Register
 public class BarcodePdfReplaceHandler extends PdfReplaceHandler {
 
-    private static final String BARCODE_TYPE_CODE128 = "code128";
-    private static final String BARCODE_TYPE_EAN = "ean";
-    private static final String BARCODE_TYPE_INTERLEAVED_2_OF_5 = "interleaved2of5";
-    private static final String BARCODE_TYPE_INTERLEAVED_2_OF_5_CHECKSUMMED = "interleaved2of5checksummed";
-
     @Override
     public boolean accepts(String protocol) {
         return "barcode".equals(protocol);
@@ -53,16 +44,7 @@ public FSImage resolveUri(String uri, UserAgentCallback userAgentCallback, int c
             throw new IllegalArgumentException("The URI is required to match the format 'barcode://type/content'");
         }
 
-        Barcode code = createBarcode(barcodeInfo[0]);
-        code.setCode(padCodeIfNecessary(code, barcodeInfo[1]));
-
-        Image awtImage = code.createAwtImage(Color.BLACK, Color.WHITE);
-
-        int scaleFactor = calculateBarcodeScaleFactor(cssWidth, cssHeight, awtImage);
-
-        awtImage = awtImage.getScaledInstance(awtImage.getWidth(null) * scaleFactor,
-                                              awtImage.getHeight(null) * scaleFactor,
-                                              Image.SCALE_REPLICATE);
+        Image awtImage = BarcodeController.generateBarcodeImage(barcodeInfo[0], barcodeInfo[1], cssWidth, cssHeight);
 
         FSImage fsImage = new ITextFSImage(com.lowagie.text.Image.getInstance(awtImage, Color.WHITE, true));
 
@@ -72,66 +54,4 @@ public FSImage resolveUri(String uri, UserAgentCallback userAgentCallback, int c
 
         return fsImage;
     }
-
-    private int calculateBarcodeScaleFactor(int cssWidth, int cssHeight, Image awtImage) {
-        return (int) Math.max(Math.ceil(cssWidth / (float) awtImage.getWidth(null)),
-                              Math.ceil(cssHeight / (float) awtImage.getHeight(null)));
-    }
-
-    /**
-     * Creates an instance of {@link Barcode} that matches the given type descriptor.
-     *
-     * @param type the requested type
-     * @return the barcode
-     */
-    @Nonnull
-    private Barcode createBarcode(String type) {
-        if (BARCODE_TYPE_CODE128.equalsIgnoreCase(type)) {
-            return new Barcode128();
-        }
-
-        if (BARCODE_TYPE_EAN.equalsIgnoreCase(type)) {
-            return new BarcodeEAN();
-        }
-
-        if (BARCODE_TYPE_INTERLEAVED_2_OF_5.equalsIgnoreCase(type)) {
-            return new BarcodeInter25();
-        }
-
-        if (BARCODE_TYPE_INTERLEAVED_2_OF_5_CHECKSUMMED.equalsIgnoreCase(type)) {
-            Barcode code = new BarcodeInter25();
-            code.setGenerateChecksum(true);
-            return code;
-        }
-
-        throw new UnsupportedOperationException(Strings.apply("Type '%s' is not supported", type));
-    }
-
-    /**
-     * Pads the code if necessary.
-     * <p>
-     * Unfortunately padding will not be added automatically when using <b>interleaved2of5</b> or
-     * <b>interleaved2of5checksummed</b>. Thus we manually prepend a zero if the code length is uneven.
-     *
-     * @param code the instance of the barcode
-     * @param src  the code from the src attribute
-     * @return the padded code, or the original code if padding was not needed
-     */
-    private String padCodeIfNecessary(Barcode code, String src) {
-        if (code instanceof BarcodeInter25) {
-            int length = BarcodeInter25.keepNumbers(src).length();
-
-            // Length is uneven and no checksum will be added
-            if (length % 2 != 0 && !code.isGenerateChecksum()) {
-                return "0" + src;
-            }
-
-            // Length is even but a checksum will be added
-            if (length % 2 == 0 && code.isGenerateChecksum()) {
-                return "0" + src;
-            }
-        }
-
-        return src;
-    }
 }

src/main/java/sirius/web/util/BarcodeController.java

@@ -16,39 +16,63 @@
 import com.google.zxing.datamatrix.DataMatrixWriter;
 import com.google.zxing.oned.Code128Writer;
 import com.google.zxing.oned.EAN13Writer;
+import com.google.zxing.oned.ITFWriter;
 import com.google.zxing.qrcode.QRCodeWriter;
+import com.lowagie.text.pdf.BarcodeInter25;
 import io.netty.handler.codec.http.HttpResponseStatus;
 import sirius.kernel.commons.Strings;
+import sirius.kernel.commons.Value;
 import sirius.kernel.di.std.Register;
 import sirius.web.controller.BasicController;
 import sirius.web.controller.Routed;
 import sirius.web.http.MimeHelper;
 import sirius.web.http.WebContext;
 
+import java.awt.Image;
+import java.awt.image.BufferedImage;
 import java.io.IOException;
 import java.io.OutputStream;
+import java.util.regex.Pattern;
 
 /**
  * Used to generate barcodes by responding to "/qr" or "/barcode".
  */
 @Register
 public class BarcodeController extends BasicController {
 
+    private static final String TYPE_QR = "qr";
+    private static final String TYPE_DATAMATRIX = "datamatrix";
+    private static final String TYPE_CODE128 = "code128";
+    private static final String TYPE_EAN = "ean";
+    private static final String TYPE_ITF = "itf";
+    private static final String TYPE_INTERLEAVED_2_OF_5 = "interleaved2of5";
+    private static final String TYPE_INTERLEAVED_2_OF_5_CHECKSUMMED = "interleaved2of5checksummed";
+
+    private static final Pattern NUMERIC = Pattern.compile("[0-9]+");
+
     /**
-     * Creates an QR code for the given content.
+     * Creates a QR code for the given content.
      * <p>
-     * The parameter <tt>content</tt> determines the contents of the qr code. The parameters <tt>with</tt> and
-     * <tt>height</tt> its dimensions.
-     * </p>
+     * The parameter <tt>content</tt> determines the contents of the qr code. The parameters <tt>width</tt> and
+     * <tt>height</tt> determine its dimensions.
      *
-     * @param ctx the current request
+     * @param webContext the current request
      * @throws Exception in case an error occurred when generating the qr code
      */
     @Routed(value = "/qr", priority = 999)
-    public void qr(WebContext ctx) throws Exception {
-        barcode(ctx, BarcodeFormat.QR_CODE);
+    public void qr(WebContext webContext) throws Exception {
+        barcode(webContext, BarcodeFormat.QR_CODE);
     }
 
+    /**
+     * Creates a barcode for the given content.
+     * <p>
+     * The parameter <tt>content</tt> determines the contents of the barcode. The parameters <tt>width</tt> and
+     * <tt>height</tt> determine its dimensions.
+     *
+     * @param webContext the current request
+     * @throws Exception in case an error occurred when generating the barcode
+     */
     @Routed(value = "/barcode", priority = 999)
     public void barcode(WebContext webContext) throws Exception {
         barcode(webContext, determineFormat(webContext.get("type").asString()));
@@ -59,39 +83,99 @@ private void barcode(WebContext webContext, BarcodeFormat format) throws WriterE
         int height = webContext.getFirstFilled("h", "height").asInt(200);
         String content = webContext.getFirstFilled("c", "content").asString();
         if (Strings.isEmpty(content)) {
-            webContext.respondWith().direct(HttpResponseStatus.BAD_REQUEST, "Usage: /barcode?type=qr&content=...&w=200&h=200");
+            webContext.respondWith()
+                      .direct(HttpResponseStatus.BAD_REQUEST, "Usage: /barcode?type=qr&content=...&w=200&h=200");
             return;
         }
 
+        content = alignContentForItfFormat(content, webContext.get("type").asString());
+
+        format = useItfFormatForGtin14(content, format);
+
         String fileType = webContext.getFirstFilled("fileType").asString("jpg");
         Writer writer = determineWriter(format);
         BitMatrix matrix = writer.encode(content, format, width, height);
         try (OutputStream out = webContext.respondWith()
-                                   .infinitelyCached()
-                                   .outputStream(HttpResponseStatus.OK,
-                                                 MimeHelper.guessMimeType("barcode." + fileType))) {
+                                          .infinitelyCached()
+                                          .outputStream(HttpResponseStatus.OK,
+                                                        MimeHelper.guessMimeType("barcode." + fileType))) {
             MatrixToImageWriter.writeToStream(matrix, fileType, out);
         }
     }
 
-    private BarcodeFormat determineFormat(String format) {
-        return switch (format) {
-            case "qr" -> BarcodeFormat.QR_CODE;
-            case "code128" -> BarcodeFormat.CODE_128;
-            case "ean" -> BarcodeFormat.EAN_13;
-            case "datamatrix" -> BarcodeFormat.DATA_MATRIX;
+    /**
+     * Generates an image of a barcode
+     *
+     * @param type    the desired barcode type
+     * @param content the content of the barcode
+     * @param width   the desired width
+     * @param height  the desired height
+     * @return a barcode of the given data as an image
+     * @throws WriterException if generating the image fails
+     */
+    public static Image generateBarcodeImage(String type, String content, int width, int height)
+            throws WriterException {
+        BarcodeFormat format = determineFormat(type);
+
+        if (!NUMERIC.matcher(content).matches() && format != BarcodeFormat.QR_CODE) {
+            // contains characters other than digits 0-9 -> directly return a blank image to prevent running into exception
+            return new BufferedImage(width != -1 ? width : 200,
+                                     height != -1 ? height : 200,
+                                     BufferedImage.TYPE_BYTE_GRAY);
+        }
+
+        content = alignContentForItfFormat(content, type);
+
+        format = useItfFormatForGtin14(content, format);
+
+        Writer writer = determineWriter(format);
+        BitMatrix matrix = writer.encode(content, format, width != -1 ? width : 200, height != -1 ? height : 200);
+        return MatrixToImageWriter.toBufferedImage(matrix);
+    }
+
+    private static BarcodeFormat determineFormat(String format) {
+        return switch (Value.of(format).toLowerCase()) {
+            case TYPE_QR -> BarcodeFormat.QR_CODE;
+            case TYPE_CODE128 -> BarcodeFormat.CODE_128;
+            case TYPE_EAN -> BarcodeFormat.EAN_13;
+            case TYPE_ITF, TYPE_INTERLEAVED_2_OF_5, TYPE_INTERLEAVED_2_OF_5_CHECKSUMMED -> BarcodeFormat.ITF;
+            case TYPE_DATAMATRIX -> BarcodeFormat.DATA_MATRIX;
             default -> throw new IllegalArgumentException(
-                    "Unsupported barcode type. Supported types are: qr, code128, ean, datamatrix");
+                    "Unsupported barcode type. Supported types are: qr, code128, ean, interleaved2of5, interleaved2of5checksummed, datamatrix");
         };
     }
 
-    private Writer determineWriter(BarcodeFormat format) {
+    private static Writer determineWriter(BarcodeFormat format) {
         return switch (format) {
             case QR_CODE -> new QRCodeWriter();
             case CODE_128 -> new Code128Writer();
             case EAN_13 -> new EAN13Writer();
+            case ITF -> new ITFWriter();
             case DATA_MATRIX -> new DataMatrixWriter();
             default -> throw new IllegalArgumentException("Unsupported barcode type!");
         };
     }
+
+    private static BarcodeFormat useItfFormatForGtin14(String content, BarcodeFormat format) {
+        // Adjust the barcode format, if "type=ean" was submitted with the request and a GTIN-14 was given
+        if (BarcodeFormat.EAN_13 == format && content.length() == 14) {
+            return BarcodeFormat.ITF;
+        }
+
+        return format;
+    }
+
+    private static String alignContentForItfFormat(String content, String format) {
+        if (TYPE_INTERLEAVED_2_OF_5_CHECKSUMMED.equalsIgnoreCase(format)) {
+            content += BarcodeInter25.getChecksum(content);
+        }
+
+        if ((TYPE_INTERLEAVED_2_OF_5.equalsIgnoreCase(format) || TYPE_INTERLEAVED_2_OF_5_CHECKSUMMED.equalsIgnoreCase(
+                format)) && BarcodeInter25.keepNumbers(content).length() % 2 != 0) {
+            // Pads the code if the length is uneven
+            content = "0" + content;
+        }
+
+        return content;
+    }
 }