001//////////////////////////////////////////////////////////////////////////////// 002// checkstyle: Checks Java source code for adherence to a set of rules. 003// Copyright (C) 2001-2018 the original author or authors. 004// 005// This library is free software; you can redistribute it and/or 006// modify it under the terms of the GNU Lesser General Public 007// License as published by the Free Software Foundation; either 008// version 2.1 of the License, or (at your option) any later version. 009// 010// This library is distributed in the hope that it will be useful, 011// but WITHOUT ANY WARRANTY; without even the implied warranty of 012// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 013// Lesser General Public License for more details. 014// 015// You should have received a copy of the GNU Lesser General Public 016// License along with this library; if not, write to the Free Software 017// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 018//////////////////////////////////////////////////////////////////////////////// 019 020package com.puppycrawl.tools.checkstyle.checks.javadoc.utils; 021 022import java.util.ArrayList; 023import java.util.List; 024import java.util.regex.Matcher; 025import java.util.regex.Pattern; 026 027import com.puppycrawl.tools.checkstyle.api.LineColumn; 028 029/** 030 * Tools for parsing block tags from a Javadoc comment. 031 * 032 * @author Nathan Naze 033 */ 034public final class BlockTagUtils { 035 036 /** Block tag pattern for a first line. */ 037 private static final Pattern BLOCK_TAG_PATTERN_FIRST_LINE = Pattern.compile( 038 "/\\*{2,}\\s*@(\\p{Alpha}+)\\s"); 039 040 /** Block tag pattern. */ 041 private static final Pattern BLOCK_TAG_PATTERN = Pattern.compile( 042 "^\\s*\\**\\s*@(\\p{Alpha}+)\\s"); 043 044 /** Closing tag. */ 045 private static final String JAVADOC_CLOSING_TAG = "*/"; 046 047 /** Prevent instantiation. */ 048 private BlockTagUtils() { 049 } 050 051 /** 052 * Extract the block tags from a Javadoc comment. 053 * @param lines The text of the comment, as separate lines. 054 * @return The tags extracted from the block. 055 */ 056 public static List<TagInfo> extractBlockTags(String... lines) { 057 final List<TagInfo> tags = new ArrayList<>(); 058 059 for (int i = 0; i < lines.length; i++) { 060 // Starting lines of a comment have a different first line pattern. 061 final boolean isFirstLine = i == 0; 062 final Pattern pattern; 063 if (isFirstLine) { 064 pattern = BLOCK_TAG_PATTERN_FIRST_LINE; 065 } 066 else { 067 pattern = BLOCK_TAG_PATTERN; 068 } 069 070 final String line = lines[i]; 071 final Matcher tagMatcher = pattern.matcher(line); 072 073 if (tagMatcher.find()) { 074 final String tagName = tagMatcher.group(1); 075 076 // offset of one for the @ character 077 final int colNum = tagMatcher.start(1) - 1; 078 final int lineNum = i + 1; 079 080 final String remainder = line.substring(tagMatcher.end(1)); 081 String tagValue = remainder.trim(); 082 083 // Handle the case where we're on the last line of a Javadoc comment. 084 if (tagValue.endsWith(JAVADOC_CLOSING_TAG)) { 085 final int endIndex = tagValue.length() - JAVADOC_CLOSING_TAG.length(); 086 tagValue = tagValue.substring(0, endIndex).trim(); 087 } 088 089 final LineColumn position = new LineColumn(lineNum, colNum); 090 tags.add(new TagInfo(tagName, tagValue, position)); 091 } 092 } 093 094 return tags; 095 } 096 097}