<?php
/*
 * Copyright 2007 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.
 */

namespace Zxing;

/**
 * Thrown when a barcode was successfully detected and decoded, but
 * was not returned because its checksum feature failed.
 *
 * @author Sean Owen
 */
final class ChecksumException extends ReaderException
{
    private static $instance;

    public static function getChecksumInstance($cause = null)
    {
        if (self::$isStackTrace) {
            return new ChecksumException($cause);
        } else {
            if (!self::$instance) {
                self::$instance = new ChecksumException($cause);
            }

            return self::$instance;
        }
    }
}