moved java files for pre-convert

src/oned/MultiFormatUPCEANReader.java

@@ -0,0 +1,125 @@
+/*
+ * Copyright 2008 ZXing authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.zxing.oned;
+
+import com.google.zxing.BarcodeFormat;
+import com.google.zxing.DecodeHintType;
+import com.google.zxing.NotFoundException;
+import com.google.zxing.Reader;
+import com.google.zxing.ReaderException;
+import com.google.zxing.Result;
+import com.google.zxing.common.BitArray;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Map;
+
+/**
+ * <p>A reader that can read all available UPC/EAN formats. If a caller wants to try to
+ * read all such formats, it is most efficient to use this implementation rather than invoke
+ * individual readers.</p>
+ *
+ * @author Sean Owen
+ */
+public final class MultiFormatUPCEANReader extends OneDReader {
+
+  private static final UPCEANReader[] EMPTY_READER_ARRAY = new UPCEANReader[0];
+
+  private final UPCEANReader[] readers;
+
+  public MultiFormatUPCEANReader(Map<DecodeHintType,?> hints) {
+    @SuppressWarnings("unchecked")
+    Collection<BarcodeFormat> possibleFormats = hints == null ? null :
+        (Collection<BarcodeFormat>) hints.get(DecodeHintType.POSSIBLE_FORMATS);
+    Collection<UPCEANReader> readers = new ArrayList<>();
+    if (possibleFormats != null) {
+      if (possibleFormats.contains(BarcodeFormat.EAN_13)) {
+        readers.add(new EAN13Reader());
+      } else if (possibleFormats.contains(BarcodeFormat.UPC_A)) {
+        readers.add(new UPCAReader());
+      }
+      if (possibleFormats.contains(BarcodeFormat.EAN_8)) {
+        readers.add(new EAN8Reader());
+      }
+      if (possibleFormats.contains(BarcodeFormat.UPC_E)) {
+        readers.add(new UPCEReader());
+      }
+    }
+    if (readers.isEmpty()) {
+      readers.add(new EAN13Reader());
+      // UPC-A is covered by EAN-13
+      readers.add(new EAN8Reader());
+      readers.add(new UPCEReader());
+    }
+    this.readers = readers.toArray(EMPTY_READER_ARRAY);
+  }
+
+  @Override
+  public Result decodeRow(int rowNumber,
+                          BitArray row,
+                          Map<DecodeHintType,?> hints) throws NotFoundException {
+    // Compute this location once and reuse it on multiple implementations
+    int[] startGuardPattern = UPCEANReader.findStartGuardPattern(row);
+    for (UPCEANReader reader : readers) {
+      try {
+        Result result = reader.decodeRow(rowNumber, row, startGuardPattern, hints);
+        // Special case: a 12-digit code encoded in UPC-A is identical to a "0"
+        // followed by those 12 digits encoded as EAN-13. Each will recognize such a code,
+        // UPC-A as a 12-digit string and EAN-13 as a 13-digit string starting with "0".
+        // Individually these are correct and their readers will both read such a code
+        // and correctly call it EAN-13, or UPC-A, respectively.
+        //
+        // In this case, if we've been looking for both types, we'd like to call it
+        // a UPC-A code. But for efficiency we only run the EAN-13 decoder to also read
+        // UPC-A. So we special case it here, and convert an EAN-13 result to a UPC-A
+        // result if appropriate.
+        //
+        // But, don't return UPC-A if UPC-A was not a requested format!
+        boolean ean13MayBeUPCA =
+            result.getBarcodeFormat() == BarcodeFormat.EAN_13 &&
+                result.getText().charAt(0) == '0';
+        @SuppressWarnings("unchecked")
+        Collection<BarcodeFormat> possibleFormats =
+            hints == null ? null : (Collection<BarcodeFormat>) hints.get(DecodeHintType.POSSIBLE_FORMATS);
+        boolean canReturnUPCA = possibleFormats == null || possibleFormats.contains(BarcodeFormat.UPC_A);
+  
+        if (ean13MayBeUPCA && canReturnUPCA) {
+          // Transfer the metadata across
+          Result resultUPCA = new Result(result.getText().substring(1),
+                                         result.getRawBytes(),
+                                         result.getResultPoints(),
+                                         BarcodeFormat.UPC_A);
+          resultUPCA.putAllMetadata(result.getResultMetadata());
+          return resultUPCA;
+        }
+        return result;
+      } catch (ReaderException ignored) {
+        // continue
+      }
+    }
+
+    throw NotFoundException.getNotFoundInstance();
+  }
+
+  @Override
+  public void reset() {
+    for (Reader reader : readers) {
+      reader.reset();
+    }
+  }
+
+}