001///////////////////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
003// Copyright (C) 2001-2024 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;
021
022import java.util.regex.Pattern;
023
024import com.puppycrawl.tools.checkstyle.StatelessCheck;
025import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
026import com.puppycrawl.tools.checkstyle.api.DetailAST;
027import com.puppycrawl.tools.checkstyle.api.TokenTypes;
028
029/**
030 * <div>
031 * Checks for {@code TODO:} comments. Actually it is a generic
032 * <a href="https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/regex/Pattern.html">
033 * pattern</a> matcher on Java comments. To check for other patterns
034 * in Java comments, set the {@code format} property.
035 * </div>
036 *
037 * <p>
038 * Using {@code TODO:} comments is a great way to keep track of tasks that need to be done.
039 * Having them reported by Checkstyle makes it very hard to forget about them.
040 * </p>
041 * <ul>
042 * <li>
043 * Property {@code format} - Specify pattern to match comments against.
044 * Type is {@code java.util.regex.Pattern}.
045 * Default value is {@code "TODO:"}.
046 * </li>
047 * </ul>
048 *
049 * <p>
050 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
051 * </p>
052 *
053 * <p>
054 * Violation Message Keys:
055 * </p>
056 * <ul>
057 * <li>
058 * {@code todo.match}
059 * </li>
060 * </ul>
061 *
062 * @since 3.0
063 */
064@StatelessCheck
065public class TodoCommentCheck
066        extends AbstractCheck {
067
068    /**
069     * A key is pointing to the warning message text in "messages.properties"
070     * file.
071     */
072    public static final String MSG_KEY = "todo.match";
073
074    /**
075     * Specify pattern to match comments against.
076     */
077    private Pattern format = Pattern.compile("TODO:");
078
079    @Override
080    public boolean isCommentNodesRequired() {
081        return true;
082    }
083
084    /**
085     * Setter to specify pattern to match comments against.
086     *
087     * @param pattern
088     *        pattern of 'todo' comment.
089     * @since 3.0
090     */
091    public void setFormat(Pattern pattern) {
092        format = pattern;
093    }
094
095    @Override
096    public int[] getDefaultTokens() {
097        return getRequiredTokens();
098    }
099
100    @Override
101    public int[] getAcceptableTokens() {
102        return getRequiredTokens();
103    }
104
105    @Override
106    public int[] getRequiredTokens() {
107        return new int[] {TokenTypes.COMMENT_CONTENT };
108    }
109
110    @Override
111    public void visitToken(DetailAST ast) {
112        final String[] lines = ast.getText().split("\n");
113
114        for (String line : lines) {
115            if (format.matcher(line).find()) {
116                log(ast, MSG_KEY, format.pattern());
117            }
118        }
119    }
120
121}