Java tutorial
/* * * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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. * */ package org.apache.qpid.server.util; import java.util.Random; import org.apache.commons.codec.digest.DigestUtils; public class StringUtil { private static final String NUMBERS = "0123456789"; private static final String LETTERS = "abcdefghijklmnopqrstuvwxwy"; private static final String OTHERS = "_-"; private static final char[] CHARACTERS = (NUMBERS + LETTERS + LETTERS.toUpperCase() + OTHERS).toCharArray(); private Random _random = new Random(); public String randomAlphaNumericString(int maxLength) { char[] result = new char[maxLength]; for (int i = 0; i < maxLength; i++) { result[i] = (char) CHARACTERS[_random.nextInt(CHARACTERS.length)]; } return new String(result); } /** * Builds a legal java name, based on manager name if possible, * this is unique for the given input. * * @param managerName * @return unique java name */ public String createUniqueJavaName(String managerName) { StringBuilder builder = new StringBuilder(); boolean initialChar = true; for (int i = 0; i < managerName.length(); i++) { char c = managerName.charAt(i); if ((initialChar && Character.isJavaIdentifierStart(c)) || (!initialChar && Character.isJavaIdentifierPart(c))) { builder.append(c); initialChar = false; } } if (builder.length() > 0) { builder.append("_"); } builder.append(DigestUtils.md5Hex(managerName)); return builder.toString(); } }