001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2020 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;
027import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
028
029/**
030 * <p>Checks that chosen statements are not line-wrapped.
031 * By default this Check restricts wrapping import and package statements,
032 * but it's possible to check any statement.
033 * </p>
034 * <ul>
035 * <li>
036 * Property {@code tokens} - tokens to check
037 * Type is {@code java.lang.String[]}.
038 * Validation type is {@code tokenSet}.
039 * Default value is:
040 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#PACKAGE_DEF">
041 * PACKAGE_DEF</a>,
042 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#IMPORT">
043 * IMPORT</a>,
044 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#STATIC_IMPORT">
045 * STATIC_IMPORT</a>.
046 * </li>
047 * </ul>
048 * <p>
049 * To configure the check to force no line-wrapping
050 * in package and import statements (default values):
051 * </p>
052 * <pre>
053 * &lt;module name=&quot;NoLineWrap&quot;/&gt;
054 * </pre>
055 * <p>Examples of line-wrapped statements (bad case):
056 * </p>
057 * <pre>
058 * package com.puppycrawl. // violation
059 *     tools.checkstyle.checks;
060 *
061 * import com.puppycrawl.tools. // violation
062 *     checkstyle.api.AbstractCheck;
063 *
064 * import static java.math. // violation
065 *     BigInteger.ZERO;
066 * </pre>
067 *
068 * <p>
069 * Examples:
070 * </p>
071 * <pre>
072 * package com.puppycrawl.tools.checkstyle. // violation
073 *   checks.whitespace;
074 *
075 * import java.lang.Object; // OK
076 * import java.lang. // violation
077 *   Integer;
078 *
079 * import static java.math. // violation
080 *   BigInteger.TEN;
081 * </pre>
082 * <pre>
083 * package com.puppycrawl.tools.checkstyle.checks.coding; // OK
084 *
085 * import java.lang. // violation
086 *   Boolean;
087 *
088 * import static java.math.BigInteger.ONE; // OK
089 * </pre>
090 *
091 * <p>
092 * To configure the check to force no line-wrapping only
093 * in import statements:
094 * </p>
095 * <pre>
096 * &lt;module name=&quot;NoLineWrap&quot;&gt;
097 *   &lt;property name="tokens" value="IMPORT"/&gt;
098 * &lt;/module&gt;
099 * </pre>
100 * <p>
101 * Example:
102 * </p>
103 * <pre>
104 * package com.puppycrawl. // OK
105 *   tools.checkstyle.checks;
106 *
107 * import java.io.*; // OK
108 * import java.lang. // violation
109 *  Boolean;
110 *
111 * import static java.math. // OK
112 * BigInteger.ZERO;
113 * </pre>
114 * <p>
115 * To configure the check to force no line-wrapping only
116 * in class, method and constructor definitions:
117 * </p>
118 * <pre>
119 * &lt;module name=&quot;NoLineWrap&quot;&gt;
120 *   &lt;property name="tokens" value="CLASS_DEF, METHOD_DEF, CTOR_DEF"/&gt;
121 * &lt;/module&gt;
122 * </pre>
123 * <p>
124 * Example:
125 * </p>
126 * <pre>
127 * public class // violation, class definition not wrapped in a single line
128 *   Foo {
129 *
130 *   public Foo() { // OK
131 *   }
132 *
133 *   public static void // violation, method definition not wrapped in a single line
134 *     doSomething() {
135 *   }
136 * }
137 *
138 * public class Bar { // OK
139 *
140 *   public // violation, constructor definition not wrapped in a single line
141 *     Bar() {
142 *   }
143 *
144 *   public int fun() { // OK
145 *   }
146 * }
147 * </pre>
148 *
149 * <p>Examples of not line-wrapped statements (good case):
150 * </p>
151 * <pre>
152 * import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
153 * import static java.math.BigInteger.ZERO;
154 * </pre>
155 * <p>
156 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
157 * </p>
158 * <p>
159 * Violation Message Keys:
160 * </p>
161 * <ul>
162 * <li>
163 * {@code no.line.wrap}
164 * </li>
165 * </ul>
166 *
167 * @since 5.8
168 */
169@StatelessCheck
170public class NoLineWrapCheck extends AbstractCheck {
171
172    /**
173     * A key is pointing to the warning message text in "messages.properties"
174     * file.
175     */
176    public static final String MSG_KEY = "no.line.wrap";
177
178    @Override
179    public int[] getDefaultTokens() {
180        return new int[] {TokenTypes.PACKAGE_DEF, TokenTypes.IMPORT, TokenTypes.STATIC_IMPORT};
181    }
182
183    @Override
184    public int[] getAcceptableTokens() {
185        return new int[] {
186            TokenTypes.IMPORT,
187            TokenTypes.STATIC_IMPORT,
188            TokenTypes.PACKAGE_DEF,
189            TokenTypes.CLASS_DEF,
190            TokenTypes.METHOD_DEF,
191            TokenTypes.CTOR_DEF,
192            TokenTypes.ENUM_DEF,
193            TokenTypes.INTERFACE_DEF,
194            TokenTypes.RECORD_DEF,
195            TokenTypes.COMPACT_CTOR_DEF,
196        };
197    }
198
199    @Override
200    public int[] getRequiredTokens() {
201        return CommonUtil.EMPTY_INT_ARRAY;
202    }
203
204    @Override
205    public void visitToken(DetailAST ast) {
206        if (!TokenUtil.areOnSameLine(ast, ast.getLastChild())) {
207            log(ast, MSG_KEY, ast.getText());
208        }
209    }
210
211}