001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache license, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the license for the specific language governing permissions and
015 * limitations under the license.
016 */
017package org.apache.logging.log4j.core.helpers;
018
019import java.security.MessageDigest;
020
021/**
022 *
023 */
024public final class NameUtil {
025
026    private static final int MASK = 0xff;
027
028    private NameUtil() {
029    }
030
031    public static String getSubName(final String name) {
032        if (name.isEmpty()) {
033            return null;
034        }
035        final int i = name.lastIndexOf('.');
036        return i > 0 ? name.substring(0, i) : "";
037    }
038
039    public static String md5(final String string) {
040        try {
041            final MessageDigest digest = MessageDigest.getInstance("MD5");
042            digest.update(string.getBytes());
043            final byte[] bytes = digest.digest();
044            final StringBuilder md5 = new StringBuilder();
045            for (final byte b : bytes) {
046                final String hex = Integer.toHexString(MASK & b);
047                if (hex.length() == 1) {
048                    md5.append('0');
049                }
050                md5.append(hex);
051            }
052            return md5.toString();
053        } catch (final Exception ex) {
054            return string;
055        }
056    }
057}