1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2026 the original author or authors.
4 //
5 // This library is free software; you can redistribute it and/or
6 // modify it under the terms of the GNU Lesser General Public
7 // License as published by the Free Software Foundation; either
8 // version 2.1 of the License, or (at your option) any later version.
9 //
10 // This library is distributed in the hope that it will be useful,
11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 // Lesser General Public License for more details.
14 //
15 // You should have received a copy of the GNU Lesser General Public
16 // License along with this library; if not, write to the Free Software
17 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 ///////////////////////////////////////////////////////////////////////////////////////////////
19
20 package com.puppycrawl.tools.checkstyle;
21
22 import java.util.HashMap;
23 import java.util.List;
24 import java.util.Map;
25
26 import com.puppycrawl.tools.checkstyle.api.AuditEvent;
27 import com.puppycrawl.tools.checkstyle.api.Violation;
28 import com.puppycrawl.tools.checkstyle.xpath.XpathQueryGenerator;
29
30 /**
31 * Catches {@code TreeWalkerAuditEvent} and generates corresponding xpath query.
32 * Stores violations and xpath queries map inside static variable
33 * for {@code XpathFileGeneratorAuditListener}.
34 * See issue <a href="https://github.com/checkstyle/checkstyle/issues/102">#102</a>
35 */
36 public class XpathFileGeneratorAstFilter extends AbstractAutomaticBean implements TreeWalkerFilter {
37
38 /** The delimiter between xpath queries. */
39 private static final String DELIMITER = " | \n";
40
41 /** Map from {@code Violation} objects to xpath queries. */
42 private static final Map<Violation, String> MESSAGE_QUERY_MAP = new HashMap<>();
43
44 /** The distance between tab stop position. */
45 private int tabWidth;
46
47 /**
48 * Creates a new {@code XpathFileGeneratorAstFilter} instance.
49 */
50 public XpathFileGeneratorAstFilter() {
51 // no code by default
52 }
53
54 /**
55 * Sets tab width.
56 *
57 * @param tabWidth the distance between tab stops
58 */
59 public void setTabWidth(int tabWidth) {
60 this.tabWidth = tabWidth;
61 }
62
63 /**
64 * Returns xpath query corresponding to violation of the
65 * {@code TreeWalkerAuditEvent} object which points to the same AST element as specified
66 * {@code AuditEvent} object.
67 *
68 * @param event the {@code AuditEvent} object.
69 * @return returns corresponding xpath query
70 */
71 public static String findCorrespondingXpathQuery(AuditEvent event) {
72 return MESSAGE_QUERY_MAP.get(event.getViolation());
73 }
74
75 @Override
76 protected void finishLocalSetup() {
77 MESSAGE_QUERY_MAP.clear();
78 }
79
80 @Override
81 public boolean accept(TreeWalkerAuditEvent event) {
82 if (event.getTokenType() != 0) {
83 final XpathQueryGenerator xpathQueryGenerator =
84 new XpathQueryGenerator(event, tabWidth);
85 final List<String> xpathQueries = xpathQueryGenerator.generate();
86 if (!xpathQueries.isEmpty()) {
87 final String query = String.join(DELIMITER, xpathQueries);
88 MESSAGE_QUERY_MAP.put(event.violation(), query);
89 }
90 }
91 return true;
92 }
93
94 }