001    /*
002     * SonarQube, open source software quality management tool.
003     * Copyright (C) 2008-2014 SonarSource
004     * mailto:contact AT sonarsource DOT com
005     *
006     * SonarQube is free software; you can redistribute it and/or
007     * modify it under the terms of the GNU Lesser General Public
008     * License as published by the Free Software Foundation; either
009     * version 3 of the License, or (at your option) any later version.
010     *
011     * SonarQube is distributed in the hope that it will be useful,
012     * but WITHOUT ANY WARRANTY; without even the implied warranty of
013     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014     * Lesser General Public License for more details.
015     *
016     * You should have received a copy of the GNU Lesser General Public License
017     * along with this program; if not, write to the Free Software Foundation,
018     * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
019     */
020    package org.sonar.api.server.rule;
021    
022    import org.apache.commons.lang.StringUtils;
023    
024    /**
025     * @since 4.2
026     */
027    public class RuleTagFormat {
028    
029      // Allowed characters are the same as those on StackOverflow
030      // see http://meta.stackoverflow.com/questions/22624/what-symbols-characters-are-not-allowed-in-tags
031      private static final String VALID_CHARACTERS_REGEX = "^[a-z0-9\\+#\\-\\.]+$";
032    
033      private RuleTagFormat() {
034        // only static methods
035      }
036    
037      public static boolean isValid(String tag) {
038        return StringUtils.isNotBlank(tag) && tag.matches(VALID_CHARACTERS_REGEX);
039      }
040    
041      public static void validate(String tag) {
042        if (!isValid(tag)) {
043          throw new IllegalArgumentException(String.format("Tag '%s' is invalid. Rule tags accept only the characters: a-z, 0-9, '+', '-', '#', '.'", tag));
044        }
045      }
046    }