001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2022 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.whitespace;
021
022import com.puppycrawl.tools.checkstyle.StatelessCheck;
023import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
024import com.puppycrawl.tools.checkstyle.api.DetailAST;
025import com.puppycrawl.tools.checkstyle.api.TokenTypes;
026import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
027
028/**
029 * <p>
030 * Checks that a token is followed by whitespace, with the exception that it
031 * does not check for whitespace after the semicolon of an empty for iterator.
032 * Use Check <a href="https://checkstyle.org/config_whitespace.html#EmptyForIteratorPad">
033 * EmptyForIteratorPad</a> to validate empty for iterators.
034 * </p>
035 * <ul>
036 * <li>
037 * Property {@code tokens} - tokens to check
038 * Type is {@code java.lang.String[]}.
039 * Validation type is {@code tokenSet}.
040 * Default value is:
041 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#COMMA">
042 * COMMA</a>,
043 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#SEMI">
044 * SEMI</a>,
045 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#TYPECAST">
046 * TYPECAST</a>,
047 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_IF">
048 * LITERAL_IF</a>,
049 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_ELSE">
050 * LITERAL_ELSE</a>,
051 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_WHILE">
052 * LITERAL_WHILE</a>,
053 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_DO">
054 * LITERAL_DO</a>,
055 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_FOR">
056 * LITERAL_FOR</a>,
057 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_DO">
058 * DO_WHILE</a>,
059 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#ELLIPSIS">
060 * ELLIPSIS</a>,
061 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LITERAL_SWITCH">
062 * LITERAL_SWITCH</a>,
063 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#LAMBDA">
064 * LAMBDA</a>.
065 * </li>
066 * </ul>
067 * <p>
068 * To configure the check:
069 * </p>
070 * <pre>
071 * &lt;module name=&quot;WhitespaceAfter&quot;/&gt;
072 * </pre>
073 * <p>Example:</p>
074 * <pre>
075 *  public void myTest() {
076 *      if (foo) {              // OK
077 *              //...
078 *      } else if(bar) {        // violation
079 *              //...
080 *      }
081 *
082 *      testMethod(foo, bar);   // OK
083 *      testMethod(foo,bar);    // violation
084 *
085 *      for (;;){}               // OK
086 *      for(;;){}                // violation, space after 'for' is required
087 *      }
088 * </pre>
089 * <p>
090 * To configure the check for whitespace only after COMMA and SEMI tokens:
091 * </p>
092 * <pre>
093 * &lt;module name=&quot;WhitespaceAfter&quot;&gt;
094 *   &lt;property name=&quot;tokens&quot; value=&quot;COMMA, SEMI&quot;/&gt;
095 * &lt;/module&gt;
096 * </pre>
097 * <p>Example:</p>
098 * <pre>
099 *     public void myTest() {
100 *         int a; int b;           // OK
101 *         int a;int b;            // violation
102 *
103 *         testMethod(foo, bar);   // OK
104 *         testMethod(foo,bar);    // violation
105 *
106 *         for(;;) {} // OK
107 *     }
108 * </pre>
109 * <p>
110 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
111 * </p>
112 * <p>
113 * Violation Message Keys:
114 * </p>
115 * <ul>
116 * <li>
117 * {@code ws.notFollowed}
118 * </li>
119 * <li>
120 * {@code ws.typeCast}
121 * </li>
122 * </ul>
123 *
124 * @since 3.0
125 */
126@StatelessCheck
127public class WhitespaceAfterCheck
128    extends AbstractCheck {
129
130    /**
131     * A key is pointing to the warning message text in "messages.properties"
132     * file.
133     */
134    public static final String MSG_WS_NOT_FOLLOWED = "ws.notFollowed";
135
136    /**
137     * A key is pointing to the warning message text in "messages.properties"
138     * file.
139     */
140    public static final String MSG_WS_TYPECAST = "ws.typeCast";
141
142    @Override
143    public int[] getDefaultTokens() {
144        return getAcceptableTokens();
145    }
146
147    @Override
148    public int[] getAcceptableTokens() {
149        return new int[] {
150            TokenTypes.COMMA,
151            TokenTypes.SEMI,
152            TokenTypes.TYPECAST,
153            TokenTypes.LITERAL_IF,
154            TokenTypes.LITERAL_ELSE,
155            TokenTypes.LITERAL_WHILE,
156            TokenTypes.LITERAL_DO,
157            TokenTypes.LITERAL_FOR,
158            TokenTypes.DO_WHILE,
159            TokenTypes.ELLIPSIS,
160            TokenTypes.LITERAL_SWITCH,
161            TokenTypes.LAMBDA,
162        };
163    }
164
165    @Override
166    public int[] getRequiredTokens() {
167        return CommonUtil.EMPTY_INT_ARRAY;
168    }
169
170    @Override
171    public void visitToken(DetailAST ast) {
172        if (ast.getType() == TokenTypes.TYPECAST) {
173            final DetailAST targetAST = ast.findFirstToken(TokenTypes.RPAREN);
174            final int[] line = getLineCodePoints(targetAST.getLineNo() - 1);
175            if (!isFollowedByWhitespace(targetAST, line)) {
176                log(targetAST, MSG_WS_TYPECAST);
177            }
178        }
179        else {
180            final int[] line = getLineCodePoints(ast.getLineNo() - 1);
181            if (!isFollowedByWhitespace(ast, line)) {
182                final Object[] message = {ast.getText()};
183                log(ast, MSG_WS_NOT_FOLLOWED, message);
184            }
185        }
186    }
187
188    /**
189     * Checks whether token is followed by a whitespace.
190     *
191     * @param targetAST Ast token.
192     * @param line Unicode code points array of line associated with the ast token.
193     * @return true if ast token is followed by a whitespace.
194     */
195    private static boolean isFollowedByWhitespace(DetailAST targetAST, int... line) {
196        final int after =
197            targetAST.getColumnNo() + targetAST.getText().length();
198        boolean followedByWhitespace = true;
199
200        if (after < line.length) {
201            final int codePoint = line[after];
202
203            followedByWhitespace = codePoint == ';'
204                || codePoint == ')'
205                || Character.isWhitespace(codePoint);
206        }
207        return followedByWhitespace;
208    }
209
210}