1 ///////////////////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code and other text files for adherence to a set of rules.
3 // Copyright (C) 2001-2025 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 * <div class="wrapper"><pre class="prettyprint"><code class="language-java">
38 * for (
39 * ; i < j; i++, j--)
40 * </code></pre></div>
41 *
42 * @since 3.4
43 */
44 @StatelessCheck
45 public class EmptyForInitializerPadCheck
46 extends AbstractCheck {
47
48 /**
49 * A key is pointing to the warning message text in "messages.properties"
50 * file.
51 */
52 public static final String MSG_PRECEDED = "ws.preceded";
53
54 /**
55 * A key is pointing to the warning message text in "messages.properties"
56 * file.
57 */
58 public static final String MSG_NOT_PRECEDED = "ws.notPreceded";
59
60 /** Semicolon literal. */
61 private static final String SEMICOLON = ";";
62
63 /** Specify policy on how to pad an empty for iterator. */
64 private PadOption option = PadOption.NOSPACE;
65
66 /**
67 * Setter to specify policy on how to pad an empty for iterator.
68 *
69 * @param optionStr string to decode option from
70 * @throws IllegalArgumentException if unable to decode
71 * @since 3.4
72 */
73 public void setOption(String optionStr) {
74 option = PadOption.valueOf(optionStr.trim().toUpperCase(Locale.ENGLISH));
75 }
76
77 @Override
78 public int[] getDefaultTokens() {
79 return getRequiredTokens();
80 }
81
82 @Override
83 public int[] getAcceptableTokens() {
84 return getRequiredTokens();
85 }
86
87 @Override
88 public int[] getRequiredTokens() {
89 return new int[] {TokenTypes.FOR_INIT};
90 }
91
92 @Override
93 public void visitToken(DetailAST ast) {
94 if (!ast.hasChildren()) {
95 final int lineIdx = ast.getLineNo() - 1;
96 final int[] line = getLineCodePoints(lineIdx);
97 final int before = ast.getColumnNo() - 1;
98 // don't check if semi at beginning of line
99 if (ast.getColumnNo() > 0 && !CodePointUtil.hasWhitespaceBefore(before, line)) {
100 if (option == PadOption.NOSPACE
101 && CommonUtil.isCodePointWhitespace(line, before)) {
102 log(ast, MSG_PRECEDED, SEMICOLON);
103 }
104 else if (option == PadOption.SPACE
105 && !CommonUtil.isCodePointWhitespace(line, before)) {
106 log(ast, MSG_NOT_PRECEDED, SEMICOLON);
107 }
108 }
109 }
110 }
111
112 }