Java tutorial
/** * Copyright (C) 2015 Orange * 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. */ package com.francetelecom.clara.cloud.commons; import com.google.common.base.Ascii; import com.google.common.base.CharMatcher; import com.google.common.net.InternetDomainName; import org.apache.commons.lang3.StringUtils; /** * */ public class FqdnHelper { public static final CharMatcher FILTERED_CHARS_IN_NAMES = CharMatcher.anyOf(".-" + "\u3002\uFF0E\uFF61"); //additional unicode characters synomym for . /** * Takes a candidate fqdn and removes all invalid parts. if this becomes empty, it returns the default. * When too long, trims by removing chars at beginning * @param candidateFqdn * @param defaultOnEmpty a valid default domain name, otherwise an exception is thrown. * @return */ public static String truncateUnsupportedCharsToValidHost(String candidateFqdn, String defaultOnEmpty) { if (defaultOnEmpty == null || defaultOnEmpty.isEmpty() || !InternetDomainName.isValid(defaultOnEmpty)) { throw new IllegalArgumentException("invalid default (" + defaultOnEmpty + ")"); } String trimmed; if (candidateFqdn == null || candidateFqdn.isEmpty()) { return defaultOnEmpty; } trimmed = InternetDomainNameCleaner.from(candidateFqdn).name(); if (trimmed.isEmpty()) { return defaultOnEmpty; } return trimmed; } /** * Sanitize a subpart of the uri so that it does not contain separators we use in domains. * e.g. when trying to construct "c-{conflictid}-{webGuiLabel}-{envLabel}-{appRelease}{appVersion}-{paasInstance}.{cfSubDomain]" * this method can be called on each individual part such as "webGuiLabel" so that they don't use * dots or dashes and get truncated to the appropriate length by trimming extra chars at beginning. * @param uriPart a part of the fqdn (e.g. "webguilabel") */ public static String sanitizeAndTruncatePart(String uriPart, int maxLength) { String sanitizedString = FILTERED_CHARS_IN_NAMES.removeFrom(uriPart); sanitizedString = Ascii.toLowerCase(sanitizedString); sanitizedString = InternetDomainNameCleaner.getFixedPart(sanitizedString, false); if (sanitizedString.length() > maxLength) { sanitizedString = StringUtils.left(sanitizedString, maxLength); } sanitizedString = InternetDomainNameCleaner.getFixedPart(sanitizedString, false); return sanitizedString; } }