001// --------------------------------------------------------------------------------
002// Copyright 2002-2025 Echo Three, LLC
003//
004// Licensed under the Apache License, Version 2.0 (the "License");
005// you may not use this file except in compliance with the License.
006// You may obtain a copy of the License at
007//
008//     http://www.apache.org/licenses/LICENSE-2.0
009//
010// Unless required by applicable law or agreed to in writing, software
011// distributed under the License is distributed on an "AS IS" BASIS,
012// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013// See the License for the specific language governing permissions and
014// limitations under the License.
015// --------------------------------------------------------------------------------
016
017package com.echothree.model.control.item.server.logic.checksum;
018
019import com.echothree.util.server.control.BaseLogic;
020
021public class BaseChecksumLogic
022        extends BaseLogic {
023
024    protected BaseChecksumLogic() {
025        super();
026    }
027
028    protected int getDigit(String alias, int offset) {
029        var result = -1;
030        var digit = alias.charAt(offset);
031
032        if(digit >= '0' && digit <= '9') {
033            result = digit - '0';
034        }
035
036        return result;
037    }
038
039}