$isStackTrace
$isStackTrace :
Thrown when a barcode was successfully detected and decoded, but was not returned because its checksum feature failed.
This includes, but is not limited to, failing checksums / error correction algorithms, being unable to locate finder timing patterns, and so on.
<?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;
}
}
}