/* * 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. */ import BarcodeFormat from '../BarcodeFormat'; import DecodeHintType from '../DecodeHintType'; import Result from '../Result'; import OneDReader from './OneDReader'; import EAN13Reader from './EAN13Reader'; import EAN8Reader from './EAN8Reader'; import UPCAReader from './UPCAReader'; import NotFoundException from '../NotFoundException'; import UPCEReader from './UPCEReader'; /** *

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.

* * @author Sean Owen */ export default class MultiFormatUPCEANReader extends OneDReader { constructor(hints) { super(); let possibleFormats = hints == null ? null : hints.get(DecodeHintType.POSSIBLE_FORMATS); let readers = []; if (possibleFormats != null) { if (possibleFormats.indexOf(BarcodeFormat.EAN_13) > -1) { readers.push(new EAN13Reader()); } if (possibleFormats.indexOf(BarcodeFormat.UPC_A) > -1) { readers.push(new UPCAReader()); } if (possibleFormats.indexOf(BarcodeFormat.EAN_8) > -1) { readers.push(new EAN8Reader()); } if (possibleFormats.indexOf(BarcodeFormat.UPC_E) > -1) { readers.push(new UPCEReader()); } } if (readers.length === 0) { readers.push(new EAN13Reader()); readers.push(new UPCAReader()); readers.push(new EAN8Reader()); readers.push(new UPCEReader()); } this.readers = readers; } decodeRow(rowNumber, row, hints) { for (let reader of this.readers) { try { // const result: Result = reader.decodeRow(rowNumber, row, startGuardPattern, hints); const result = reader.decodeRow(rowNumber, row, 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! const ean13MayBeUPCA = result.getBarcodeFormat() === BarcodeFormat.EAN_13 && result.getText().charAt(0) === '0'; // @SuppressWarnings("unchecked") const possibleFormats = hints == null ? null : hints.get(DecodeHintType.POSSIBLE_FORMATS); const canReturnUPCA = possibleFormats == null || possibleFormats.includes(BarcodeFormat.UPC_A); if (ean13MayBeUPCA && canReturnUPCA) { const rawBytes = result.getRawBytes(); // Transfer the metadata across const resultUPCA = new Result(result.getText().substring(1), rawBytes, (rawBytes ? rawBytes.length : null), result.getResultPoints(), BarcodeFormat.UPC_A); resultUPCA.putAllMetadata(result.getResultMetadata()); return resultUPCA; } return result; } catch (err) { // continue; } } throw new NotFoundException(); } reset() { for (let reader of this.readers) { reader.reset(); } } }