1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2024 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.checks.whitespace;
21
22 import java.util.Locale;
23
24 import com.puppycrawl.tools.checkstyle.StatelessCheck;
25 import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
26 import com.puppycrawl.tools.checkstyle.api.DetailAST;
27 import com.puppycrawl.tools.checkstyle.api.TokenTypes;
28 import com.puppycrawl.tools.checkstyle.utils.CodePointUtil;
29 import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
30
31 /**
32 * <div>
33 * Checks the padding of an empty for initializer; that is whether a white
34 * space is required at an empty for initializer, or such white space is
35 * forbidden. No check occurs if there is a line wrap at the initializer, as in
36 * </div>
37 * <pre>
38 * for (
39 * ; i < j; i++, j--)
40 * </pre>
41 * <ul>
42 * <li>
43 * Property {@code option} - Specify policy on how to pad an empty for iterator.
44 * Type is {@code com.puppycrawl.tools.checkstyle.checks.whitespace.PadOption}.
45 * Default value is {@code nospace}.
46 * </li>
47 * </ul>
48 *
49 * <p>
50 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
51 * </p>
52 *
53 * <p>
54 * Violation Message Keys:
55 * </p>
56 * <ul>
57 * <li>
58 * {@code ws.notPreceded}
59 * </li>
60 * <li>
61 * {@code ws.preceded}
62 * </li>
63 * </ul>
64 *
65 * @since 3.4
66 */
67 @StatelessCheck
68 public class EmptyForInitializerPadCheck
69 extends AbstractCheck {
70
71 /**
72 * A key is pointing to the warning message text in "messages.properties"
73 * file.
74 */
75 public static final String MSG_PRECEDED = "ws.preceded";
76
77 /**
78 * A key is pointing to the warning message text in "messages.properties"
79 * file.
80 */
81 public static final String MSG_NOT_PRECEDED = "ws.notPreceded";
82
83 /** Semicolon literal. */
84 private static final String SEMICOLON = ";";
85
86 /** Specify policy on how to pad an empty for iterator. */
87 private PadOption option = PadOption.NOSPACE;
88
89 /**
90 * Setter to specify policy on how to pad an empty for iterator.
91 *
92 * @param optionStr string to decode option from
93 * @throws IllegalArgumentException if unable to decode
94 * @since 3.4
95 */
96 public void setOption(String optionStr) {
97 option = PadOption.valueOf(optionStr.trim().toUpperCase(Locale.ENGLISH));
98 }
99
100 @Override
101 public int[] getDefaultTokens() {
102 return getRequiredTokens();
103 }
104
105 @Override
106 public int[] getAcceptableTokens() {
107 return getRequiredTokens();
108 }
109
110 @Override
111 public int[] getRequiredTokens() {
112 return new int[] {TokenTypes.FOR_INIT};
113 }
114
115 @Override
116 public void visitToken(DetailAST ast) {
117 if (!ast.hasChildren()) {
118 final int lineIdx = ast.getLineNo() - 1;
119 final int[] line = getLineCodePoints(lineIdx);
120 final int before = ast.getColumnNo() - 1;
121 // don't check if semi at beginning of line
122 if (ast.getColumnNo() > 0 && !CodePointUtil.hasWhitespaceBefore(before, line)) {
123 if (option == PadOption.NOSPACE
124 && CommonUtil.isCodePointWhitespace(line, before)) {
125 log(ast, MSG_PRECEDED, SEMICOLON);
126 }
127 else if (option == PadOption.SPACE
128 && !CommonUtil.isCodePointWhitespace(line, before)) {
129 log(ast, MSG_NOT_PRECEDED, SEMICOLON);
130 }
131 }
132 }
133 }
134
135 }