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.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 * <p>
028 * Checks that {@code static}, non-{@code final} variable names conform to a specified pattern.
029 * </p>
030 * <ul>
031 * <li>
032 * Property {@code format} - Specifies valid identifiers. Default value is
033 * {@code "^[a-z][a-zA-Z0-9]*$"}.
034 * </li>
035 * <li>
036 * Property {@code applyToPublic} - Controls whether to apply the check to public member.
037 * Default value is {@code true}.
038 * </li>
039 * <li>
040 * Property {@code applyToProtected} - Controls whether to apply the check to protected member.
041 * Default value is {@code true}.
042 * </li>
043 * <li>
044 * Property {@code applyToPackage} - Controls whether to apply the check to package-private member.
045 * Default value is {@code true}.
046 * </li>
047 * <li>
048 * Property {@code applyToPrivate} - Controls whether to apply the check to private member.
049 * Default value is {@code true}.
050 * </li>
051 * </ul>
052 * <p>
053 * An example of how to configure the check is:
054 * </p>
055 * <pre>
056 * &lt;module name="StaticVariableName"/&gt;
057 * </pre>
058 * <p>
059 * An example of how to configure the check for names that begin with
060 * a lower case letter, followed by letters, digits, and underscores is:
061 * </p>
062 * <pre>
063 * &lt;module name="StaticVariableName"&gt;
064 *   &lt;property name="format" value="^[a-z](_?[a-zA-Z0-9]+)*$"/&gt;
065 * &lt;/module&gt;
066 * </pre>
067 *
068 * @since 3.0
069 */
070public class StaticVariableNameCheck
071    extends AbstractAccessControlNameCheck {
072
073    /** Creates a new {@code StaticVariableNameCheck} instance. */
074    public StaticVariableNameCheck() {
075        super("^[a-z][a-zA-Z0-9]*$");
076    }
077
078    @Override
079    public int[] getDefaultTokens() {
080        return getRequiredTokens();
081    }
082
083    @Override
084    public int[] getAcceptableTokens() {
085        return getRequiredTokens();
086    }
087
088    @Override
089    public int[] getRequiredTokens() {
090        return new int[] {TokenTypes.VARIABLE_DEF};
091    }
092
093    @Override
094    protected final boolean mustCheckName(DetailAST ast) {
095        final DetailAST modifiersAST =
096            ast.findFirstToken(TokenTypes.MODIFIERS);
097        final boolean isStatic = modifiersAST.findFirstToken(TokenTypes.LITERAL_STATIC) != null;
098        final boolean isFinal = modifiersAST.findFirstToken(TokenTypes.FINAL) != null;
099
100        return isStatic
101                && !isFinal
102                && shouldCheckInScope(modifiersAST)
103                && !ScopeUtil.isInInterfaceOrAnnotationBlock(ast);
104    }
105
106}