From 1baa8f33116531b383868f17e0c5f348f23517ce Mon Sep 17 00:00:00 2001
From: Ralf Kistner <ralf@embarkmobile.com>
Date: Fri, 31 Jan 2014 17:21:02 +0200
Subject: [PATCH] Specify allowed EAN extensions as a hint.

---
 .../java/com/google/zxing/DecodeHintType.java  |  9 +++++++++
 .../com/google/zxing/oned/UPCEANReader.java    | 18 ++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/core/src/main/java/com/google/zxing/DecodeHintType.java b/core/src/main/java/com/google/zxing/DecodeHintType.java
index 54a1c8086..90d0a3e02 100644
--- a/core/src/main/java/com/google/zxing/DecodeHintType.java
+++ b/core/src/main/java/com/google/zxing/DecodeHintType.java
@@ -88,6 +88,15 @@ public enum DecodeHintType {
    */
   NEED_RESULT_POINT_CALLBACK(ResultPointCallback.class),
 
+
+  /**
+   * Allowed extension lengths for EAN or UPC barcodes.
+   * Other formats will ignore this.
+   * Maps to an {@code int[]} of the allowed extension lengths, for example [2], [5], or [2, 5].
+   * If it is optional to have an extension, do not set this hint.
+   */
+  ALLOWED_EAN_EXTENSIONS(int[].class);
+
   // End of enumeration values.
   ;
 
diff --git a/core/src/main/java/com/google/zxing/oned/UPCEANReader.java b/core/src/main/java/com/google/zxing/oned/UPCEANReader.java
index 91afbe36d..349d4632d 100644
--- a/core/src/main/java/com/google/zxing/oned/UPCEANReader.java
+++ b/core/src/main/java/com/google/zxing/oned/UPCEANReader.java
@@ -194,15 +194,33 @@ public abstract class UPCEANReader extends OneDReader {
             new ResultPoint(right, (float) rowNumber)},
         format);
 
+    int extensionLength = 0;
+
     try {
       Result extensionResult = extensionReader.decodeRow(rowNumber, row, endRange[1]);
       decodeResult.putMetadata(ResultMetadataType.UPC_EAN_EXTENSION, extensionResult.getText());
       decodeResult.putAllMetadata(extensionResult.getResultMetadata());
       decodeResult.addResultPoints(extensionResult.getResultPoints());
+      extensionLength = extensionResult.getText().length();
     } catch (ReaderException re) {
       // continue
     }
 
+    int[] allowedExtensions = hints == null ? null :
+        (int[])hints.get(DecodeHintType.ALLOWED_EAN_EXTENSIONS);
+    if(allowedExtensions != null) {
+      boolean valid = false;
+      for (int length : allowedExtensions) {
+        if(extensionLength == length) {
+          valid = true;
+          break;
+        }
+      }
+      if(!valid) {
+        throw NotFoundException.getNotFoundInstance();
+      }
+    }
+
     if (format == BarcodeFormat.EAN_13 || format == BarcodeFormat.UPC_A) {
       String countryID = eanManSupport.lookupCountryIdentifier(resultString);
       if (countryID != null) {