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 java.util.Locale;
023
024import com.puppycrawl.tools.checkstyle.StatelessCheck;
025import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
026import com.puppycrawl.tools.checkstyle.api.DetailAST;
027import com.puppycrawl.tools.checkstyle.api.TokenTypes;
028import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
029
030/**
031 * <p>
032 * Checks line wrapping with separators.
033 * </p>
034 * <ul>
035 * <li>
036 * Property {@code option} - Specify policy on how to wrap lines.
037 * Default value is {@code eol}.
038 * </li>
039 * <li>
040 * Property {@code tokens} - tokens to check
041 * Default value is:
042 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#DOT">
043 * DOT</a>,
044 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#COMMA">
045 * COMMA</a>.
046 * </li>
047 * </ul>
048 * <p>
049 * Code example for comma and dot at the new line:
050 * </p>
051 * <pre>
052 * s
053 *     .isEmpty();
054 * foo(i
055 *     ,s);
056 * </pre>
057 *  <p>
058 * To configure the check:
059 * </p>
060 * <pre>
061 * &lt;module name=&quot;SeparatorWrap&quot;/&gt;
062 * </pre>
063 * <p>
064 * Code example for comma and dot at the previous line:
065 * </p>
066 * <pre>
067 * s.
068 *     isEmpty();
069 * foo(i,
070 *     s);
071 * </pre>
072 * <p>
073 * Example for checking method reference at new line (good case and bad case):
074 * </p>
075 * <pre>
076 * Arrays.sort(stringArray, String:: // violation
077 *     compareToIgnoreCase);
078 * Arrays.sort(stringArray, String
079 *     ::compareToIgnoreCase); // good
080 * </pre>
081 * <p>
082 * To configure the check for
083 * <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#METHOD_REF">
084 * METHOD_REF</a> at new line:
085 * </p>
086 * <pre>
087 * &lt;module name=&quot;SeparatorWrap&quot;&gt;
088 *   &lt;property name=&quot;tokens&quot; value=&quot;METHOD_REF&quot;/&gt;
089 *   &lt;property name=&quot;option&quot; value=&quot;nl&quot;/&gt;
090 * &lt;/module&gt;
091 * </pre>
092 * <p>
093 * To configure the check for comma at the new line:
094 * </p>
095 * <pre>
096 * &lt;module name=&quot;SeparatorWrap&quot;&gt;
097 *   &lt;property name=&quot;tokens&quot; value=&quot;COMMA&quot;/&gt;
098 *   &lt;property name=&quot;option&quot; value=&quot;nl&quot;/&gt;
099 * &lt;/module&gt;
100 * </pre>
101 *
102 * @since 5.8
103 */
104@StatelessCheck
105public class SeparatorWrapCheck
106    extends AbstractCheck {
107
108    /**
109     * A key is pointing to the warning message text in "messages.properties"
110     * file.
111     */
112    public static final String MSG_LINE_PREVIOUS = "line.previous";
113
114    /**
115     * A key is pointing to the warning message text in "messages.properties"
116     * file.
117     */
118    public static final String MSG_LINE_NEW = "line.new";
119
120    /** Specify policy on how to wrap lines. */
121    private WrapOption option = WrapOption.EOL;
122
123    /**
124     * Setter to specify policy on how to wrap lines.
125     * @param optionStr string to decode option from
126     * @throws IllegalArgumentException if unable to decode
127     */
128    public void setOption(String optionStr) {
129        option = WrapOption.valueOf(optionStr.trim().toUpperCase(Locale.ENGLISH));
130    }
131
132    @Override
133    public int[] getDefaultTokens() {
134        return new int[] {
135            TokenTypes.DOT,
136            TokenTypes.COMMA,
137        };
138    }
139
140    @Override
141    public int[] getAcceptableTokens() {
142        return new int[] {
143            TokenTypes.DOT,
144            TokenTypes.COMMA,
145            TokenTypes.SEMI,
146            TokenTypes.ELLIPSIS,
147            TokenTypes.AT,
148            TokenTypes.LPAREN,
149            TokenTypes.RPAREN,
150            TokenTypes.ARRAY_DECLARATOR,
151            TokenTypes.RBRACK,
152            TokenTypes.METHOD_REF,
153        };
154    }
155
156    @Override
157    public int[] getRequiredTokens() {
158        return CommonUtil.EMPTY_INT_ARRAY;
159    }
160
161    @Override
162    public void visitToken(DetailAST ast) {
163        final String text = ast.getText();
164        final int colNo = ast.getColumnNo();
165        final int lineNo = ast.getLineNo();
166        final String currentLine = getLines()[lineNo - 1];
167        final String substringAfterToken =
168                currentLine.substring(colNo + text.length()).trim();
169        final String substringBeforeToken =
170                currentLine.substring(0, colNo).trim();
171
172        if (option == WrapOption.EOL
173                && substringBeforeToken.isEmpty()) {
174            log(ast, MSG_LINE_PREVIOUS, text);
175        }
176        else if (option == WrapOption.NL
177                 && substringAfterToken.isEmpty()) {
178            log(ast, MSG_LINE_NEW, text);
179        }
180    }
181
182}