001///////////////////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
003// Copyright (C) 2001-2025 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.naming;
021
022import com.puppycrawl.tools.checkstyle.api.DetailAST;
023import com.puppycrawl.tools.checkstyle.api.TokenTypes;
024import com.puppycrawl.tools.checkstyle.utils.ScopeUtil;
025
026/**
027 * <div>
028 * Checks that constant names conform to a specified pattern.
029 * A <em>constant</em> is a <strong>static</strong> and <strong>final</strong>
030 * field or an interface/annotation field, except
031 * <strong>serialVersionUID</strong> and <strong>serialPersistentFields
032 * </strong>.
033 * </div>
034 *
035 * <ul>
036 * <li>
037 * Property {@code applyToPackage} - Control if check should apply to package-private members.
038 * Type is {@code boolean}.
039 * Default value is {@code true}.
040 * Since version 5.0
041 * </li>
042 * <li>
043 * Property {@code applyToPrivate} - Control if check should apply to private members.
044 * Type is {@code boolean}.
045 * Default value is {@code true}.
046 * Since version 5.0
047 * </li>
048 * <li>
049 * Property {@code applyToProtected} - Control if check should apply to protected members.
050 * Type is {@code boolean}.
051 * Default value is {@code true}.
052 * Since version 5.0
053 * </li>
054 * <li>
055 * Property {@code applyToPublic} - Control if check should apply to public members.
056 * Type is {@code boolean}.
057 * Default value is {@code true}.
058 * Since version 5.0
059 * </li>
060 * <li>
061 * Property {@code format} - Sets the pattern to match valid identifiers.
062 * Type is {@code java.util.regex.Pattern}.
063 * Default value is {@code "^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$"}.
064 * </li>
065 * </ul>
066 *
067 * <p>
068 * Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
069 * </p>
070 *
071 * <p>
072 * Violation Message Keys:
073 * </p>
074 * <ul>
075 * <li>
076 * {@code name.invalidPattern}
077 * </li>
078 * </ul>
079 *
080 * @since 3.0
081 */
082public class ConstantNameCheck
083    extends AbstractAccessControlNameCheck {
084
085    /** Creates a new {@code ConstantNameCheck} instance. */
086    public ConstantNameCheck() {
087        super("^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$");
088    }
089
090    @Override
091    public int[] getDefaultTokens() {
092        return getRequiredTokens();
093    }
094
095    @Override
096    public int[] getAcceptableTokens() {
097        return getRequiredTokens();
098    }
099
100    @Override
101    public int[] getRequiredTokens() {
102        return new int[] {TokenTypes.VARIABLE_DEF};
103    }
104
105    @Override
106    protected final boolean mustCheckName(DetailAST ast) {
107        boolean returnValue = false;
108
109        final DetailAST modifiersAST =
110            ast.findFirstToken(TokenTypes.MODIFIERS);
111        final boolean isStaticFinal =
112            modifiersAST.findFirstToken(TokenTypes.LITERAL_STATIC) != null
113                && modifiersAST.findFirstToken(TokenTypes.FINAL) != null
114            || ScopeUtil.isInAnnotationBlock(ast)
115            || ScopeUtil.isInInterfaceBlock(ast);
116        if (isStaticFinal && shouldCheckInScope(modifiersAST)
117                        && !ScopeUtil.isInCodeBlock(ast)) {
118            // Handle the serialVersionUID and serialPersistentFields constants
119            // which are used for Serialization. Cannot enforce rules on it. :-)
120            final DetailAST nameAST = ast.findFirstToken(TokenTypes.IDENT);
121            if (!"serialVersionUID".equals(nameAST.getText())
122                && !"serialPersistentFields".equals(nameAST.getText())) {
123                returnValue = true;
124            }
125        }
126
127        return returnValue;
128    }
129
130}