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.coding;
21
22 import com.puppycrawl.tools.checkstyle.StatelessCheck;
23 import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
24 import com.puppycrawl.tools.checkstyle.api.DetailAST;
25 import com.puppycrawl.tools.checkstyle.api.TokenTypes;
26 import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
27 import com.puppycrawl.tools.checkstyle.utils.JavadocUtil;
28 import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
29
30 /**
31 * <p>
32 * Checks for illegal tokens. By default labels are prohibited.
33 * </p>
34 * <p>
35 * Rationale: Certain language features can harm readability, lead to
36 * confusion or are not obvious to novice developers. Other features
37 * may be discouraged in certain frameworks, such as not having
38 * native methods in EJB components.
39 * </p>
40 * <p>
41 * An example of how to configure the check is:
42 * </p>
43 * <pre>
44 * <module name="IllegalToken"/>
45 * </pre>
46 * <p> An example of how to configure the check to forbid
47 * a {@link TokenTypes#LITERAL_NATIVE LITERAL_NATIVE} token is:
48 * </p>
49 * <pre>
50 * <module name="IllegalToken">
51 * <property name="tokens" value="LITERAL_NATIVE"/>
52 * </module>
53 * </pre>
54 */
55 @StatelessCheck
56 public class IllegalTokenCheck
57 extends AbstractCheck {
58
59 /**
60 * A key is pointing to the warning message text in "messages.properties"
61 * file.
62 */
63 public static final String MSG_KEY = "illegal.token";
64
65 @Override
66 public int[] getDefaultTokens() {
67 return new int[] {
68 TokenTypes.LABELED_STAT,
69 };
70 }
71
72 @Override
73 public int[] getAcceptableTokens() {
74 return TokenUtil.getAllTokenIds();
75 }
76
77 @Override
78 public int[] getRequiredTokens() {
79 return CommonUtil.EMPTY_INT_ARRAY;
80 }
81
82 @Override
83 public boolean isCommentNodesRequired() {
84 return true;
85 }
86
87 @Override
88 public void visitToken(DetailAST ast) {
89 log(
90 ast,
91 MSG_KEY,
92 convertToString(ast)
93 );
94 }
95
96 /**
97 * Converts given AST node to string representation.
98 * @param ast node to be represented as string
99 * @return string representation of AST node
100 */
101 private static String convertToString(DetailAST ast) {
102 final String tokenText;
103 switch (ast.getType()) {
104 case TokenTypes.LABELED_STAT:
105 tokenText = ast.getFirstChild().getText() + ast.getText();
106 break;
107 // multiline tokens need to become singlelined
108 case TokenTypes.COMMENT_CONTENT:
109 tokenText = JavadocUtil.escapeAllControlChars(ast.getText());
110 break;
111 default:
112 tokenText = ast.getText();
113 break;
114 }
115 return tokenText;
116 }
117
118 }