1 ////////////////////////////////////////////////////////////////////////////////
2 // checkstyle: Checks Java source code for adherence to a set of rules.
3 // Copyright (C) 2001-2019 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.CommonUtil;
29
30 /**
31 * <p>
32 * Checks line wrapping for operators.
33 * The policy to verify is specified using the {@link WrapOption} class
34 * and defaults to {@link WrapOption#NL}.
35 * </p>
36 * <p> By default the check will check the following operators:
37 * {@link TokenTypes#BAND BAND},
38 * {@link TokenTypes#BOR BOR},
39 * {@link TokenTypes#BSR BSR},
40 * {@link TokenTypes#BXOR BXOR},
41 * {@link TokenTypes#COLON COLON},
42 * {@link TokenTypes#DIV DIV},
43 * {@link TokenTypes#EQUAL EQUAL},
44 * {@link TokenTypes#GE GE},
45 * {@link TokenTypes#GT GT},
46 * {@link TokenTypes#LAND LAND},
47 * {@link TokenTypes#LE LE},
48 * {@link TokenTypes#LITERAL_INSTANCEOF LITERAL_INSTANCEOF},
49 * {@link TokenTypes#LOR LOR},
50 * {@link TokenTypes#LT LT},
51 * {@link TokenTypes#MINUS MINUS},
52 * {@link TokenTypes#MOD MOD},
53 * {@link TokenTypes#NOT_EQUAL NOT_EQUAL},
54 * {@link TokenTypes#PLUS PLUS},
55 * {@link TokenTypes#QUESTION QUESTION},
56 * {@link TokenTypes#SL SL},
57 * {@link TokenTypes#SR SR},
58 * {@link TokenTypes#STAR STAR}.
59 * Other acceptable tokens are
60 * {@link TokenTypes#ASSIGN ASSIGN},
61 * {@link TokenTypes#BAND_ASSIGN BAND_ASSIGN},
62 * {@link TokenTypes#BOR_ASSIGN BOR_ASSIGN},
63 * {@link TokenTypes#BSR_ASSIGN BSR_ASSIGN},
64 * {@link TokenTypes#BXOR_ASSIGN BXOR_ASSIGN},
65 * {@link TokenTypes#DIV_ASSIGN DIV_ASSIGN},
66 * {@link TokenTypes#MINUS_ASSIGN MINUS_ASSIGN},
67 * {@link TokenTypes#MOD_ASSIGN MOD_ASSIGN},
68 * {@link TokenTypes#PLUS_ASSIGN PLUS_ASSIGN},
69 * {@link TokenTypes#SL_ASSIGN SL_ASSIGN},
70 * {@link TokenTypes#SR_ASSIGN SR_ASSIGN},
71 * {@link TokenTypes#STAR_ASSIGN STAR_ASSIGN}.
72 * {@link TokenTypes#METHOD_REF METHOD_REF}.
73 * </p>
74 * <p>
75 * An example of how to configure the check is:
76 * </p>
77 * <pre>
78 * <module name="OperatorWrap"/>
79 * </pre>
80 * <p> An example of how to configure the check for assignment operators at the
81 * end of a line is:
82 * </p>
83 * <pre>
84 * <module name="OperatorWrap">
85 * <property name="tokens"
86 * value="ASSIGN,DIV_ASSIGN,PLUS_ASSIGN,MINUS_ASSIGN,STAR_ASSIGN,MOD_ASSIGN
87 * ,SR_ASSIGN,BSR_ASSIGN,SL_ASSIGN,BXOR_ASSIGN,BOR_ASSIGN,BAND_ASSIGN"/>
88 * <property name="option" value="eol"/>
89 * </module>
90 * </pre>
91 *
92 */
93 @StatelessCheck
94 public class OperatorWrapCheck
95 extends AbstractCheck {
96
97 /**
98 * A key is pointing to the warning message text in "messages.properties"
99 * file.
100 */
101 public static final String MSG_LINE_NEW = "line.new";
102
103 /**
104 * A key is pointing to the warning message text in "messages.properties"
105 * file.
106 */
107 public static final String MSG_LINE_PREVIOUS = "line.previous";
108
109 /** The policy to enforce. */
110 private WrapOption option = WrapOption.NL;
111
112 /**
113 * Set the option to enforce.
114 * @param optionStr string to decode option from
115 * @throws IllegalArgumentException if unable to decode
116 */
117 public void setOption(String optionStr) {
118 option = WrapOption.valueOf(optionStr.trim().toUpperCase(Locale.ENGLISH));
119 }
120
121 @Override
122 public int[] getDefaultTokens() {
123 return new int[] {
124 TokenTypes.QUESTION, // '?'
125 TokenTypes.COLON, // ':' (not reported for a case)
126 TokenTypes.EQUAL, // "=="
127 TokenTypes.NOT_EQUAL, // "!="
128 TokenTypes.DIV, // '/'
129 TokenTypes.PLUS, //' +' (unary plus is UNARY_PLUS)
130 TokenTypes.MINUS, // '-' (unary minus is UNARY_MINUS)
131 TokenTypes.STAR, // '*'
132 TokenTypes.MOD, // '%'
133 TokenTypes.SR, // ">>"
134 TokenTypes.BSR, // ">>>"
135 TokenTypes.GE, // ">="
136 TokenTypes.GT, // ">"
137 TokenTypes.SL, // "<<"
138 TokenTypes.LE, // "<="
139 TokenTypes.LT, // '<'
140 TokenTypes.BXOR, // '^'
141 TokenTypes.BOR, // '|'
142 TokenTypes.LOR, // "||"
143 TokenTypes.BAND, // '&'
144 TokenTypes.LAND, // "&&"
145 TokenTypes.TYPE_EXTENSION_AND,
146 TokenTypes.LITERAL_INSTANCEOF,
147 };
148 }
149
150 @Override
151 public int[] getAcceptableTokens() {
152 return new int[] {
153 TokenTypes.QUESTION, // '?'
154 TokenTypes.COLON, // ':' (not reported for a case)
155 TokenTypes.EQUAL, // "=="
156 TokenTypes.NOT_EQUAL, // "!="
157 TokenTypes.DIV, // '/'
158 TokenTypes.PLUS, //' +' (unary plus is UNARY_PLUS)
159 TokenTypes.MINUS, // '-' (unary minus is UNARY_MINUS)
160 TokenTypes.STAR, // '*'
161 TokenTypes.MOD, // '%'
162 TokenTypes.SR, // ">>"
163 TokenTypes.BSR, // ">>>"
164 TokenTypes.GE, // ">="
165 TokenTypes.GT, // ">"
166 TokenTypes.SL, // "<<"
167 TokenTypes.LE, // "<="
168 TokenTypes.LT, // '<'
169 TokenTypes.BXOR, // '^'
170 TokenTypes.BOR, // '|'
171 TokenTypes.LOR, // "||"
172 TokenTypes.BAND, // '&'
173 TokenTypes.LAND, // "&&"
174 TokenTypes.LITERAL_INSTANCEOF,
175 TokenTypes.TYPE_EXTENSION_AND,
176 TokenTypes.ASSIGN, // '='
177 TokenTypes.DIV_ASSIGN, // "/="
178 TokenTypes.PLUS_ASSIGN, // "+="
179 TokenTypes.MINUS_ASSIGN, //"-="
180 TokenTypes.STAR_ASSIGN, // "*="
181 TokenTypes.MOD_ASSIGN, // "%="
182 TokenTypes.SR_ASSIGN, // ">>="
183 TokenTypes.BSR_ASSIGN, // ">>>="
184 TokenTypes.SL_ASSIGN, // "<<="
185 TokenTypes.BXOR_ASSIGN, // "^="
186 TokenTypes.BOR_ASSIGN, // "|="
187 TokenTypes.BAND_ASSIGN, // "&="
188 TokenTypes.METHOD_REF, // "::"
189 };
190 }
191
192 @Override
193 public int[] getRequiredTokens() {
194 return CommonUtil.EMPTY_INT_ARRAY;
195 }
196
197 @Override
198 public void visitToken(DetailAST ast) {
199 final DetailAST parent = ast.getParent();
200 //we do not want to check colon for cases and defaults
201 if (parent.getType() != TokenTypes.LITERAL_DEFAULT
202 && parent.getType() != TokenTypes.LITERAL_CASE) {
203 final String text = ast.getText();
204 final int colNo = ast.getColumnNo();
205 final int lineNo = ast.getLineNo();
206 final String currentLine = getLine(lineNo - 1);
207
208 // Check if rest of line is whitespace, and not just the operator
209 // by itself. This last bit is to handle the operator on a line by
210 // itself.
211 if (option == WrapOption.NL
212 && !text.equals(currentLine.trim())
213 && CommonUtil.isBlank(currentLine.substring(colNo + text.length()))) {
214 log(ast, MSG_LINE_NEW, text);
215 }
216 else if (option == WrapOption.EOL
217 && CommonUtil.hasWhitespaceBefore(colNo - 1, currentLine)) {
218 log(ast, MSG_LINE_PREVIOUS, text);
219 }
220 }
221 }
222
223 }