001////////////////////////////////////////////////////////////////////////////////
002// checkstyle: Checks Java source code for adherence to a set of rules.
003// Copyright (C) 2001-2016 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 java.util.regex.Pattern;
023
024import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
025import com.puppycrawl.tools.checkstyle.api.DetailAST;
026import com.puppycrawl.tools.checkstyle.api.TokenTypes;
027import com.puppycrawl.tools.checkstyle.utils.CommonUtils;
028
029/**
030 * <p>
031 * Ensures that the names of abstract classes conforming to some
032 * regular expression and check that {@code abstract} modifier exists.
033 * </p>
034 * <p>
035 * Rationale: Abstract classes are convenience base class
036 * implementations of interfaces, not types as such. As such
037 * they should be named to indicate this. Also if names of classes
038 * starts with 'Abstract' it's very convenient that they will
039 * have abstract modifier.
040 * </p>
041 *
042 * @author <a href="mailto:simon@redhillconsulting.com.au">Simon Harris</a>
043 * @author <a href="mailto:solid.danil@gmail.com">Danil Lopatin</a>
044 */
045public final class AbstractClassNameCheck extends AbstractCheck {
046
047    /**
048     * A key is pointing to the warning message text in "messages.properties"
049     * file.
050     */
051    public static final String MSG_ILLEGAL_ABSTRACT_CLASS_NAME = "illegal.abstract.class.name";
052
053    /**
054     * A key is pointing to the warning message text in "messages.properties"
055     * file.
056     */
057    public static final String MSG_NO_ABSTRACT_CLASS_MODIFIER = "no.abstract.class.modifier";
058
059    /** Whether to ignore checking the modifier. */
060    private boolean ignoreModifier;
061
062    /** Whether to ignore checking the name. */
063    private boolean ignoreName;
064
065    /** The format string of the regexp. */
066    private String format = "^Abstract.+$";
067
068    /** The regexp to match against. */
069    private Pattern regexp = Pattern.compile(format);
070
071    /**
072     * Whether to ignore checking for the {@code abstract} modifier.
073     * @param value new value
074     */
075    public void setIgnoreModifier(boolean value) {
076        ignoreModifier = value;
077    }
078
079    /**
080     * Whether to ignore checking the name.
081     * @param value new value.
082     */
083    public void setIgnoreName(boolean value) {
084        ignoreName = value;
085    }
086
087    /**
088     * Set the format to the specified regular expression.
089     * @param format a {@code String} value
090     * @throws org.apache.commons.beanutils.ConversionException unable to parse format
091     */
092    public void setFormat(String format) {
093        this.format = format;
094        regexp = CommonUtils.createPattern(format);
095    }
096
097    @Override
098    public int[] getDefaultTokens() {
099        return new int[] {TokenTypes.CLASS_DEF};
100    }
101
102    @Override
103    public int[] getRequiredTokens() {
104        return new int[] {TokenTypes.CLASS_DEF};
105    }
106
107    @Override
108    public int[] getAcceptableTokens() {
109        return new int[] {TokenTypes.CLASS_DEF};
110    }
111
112    @Override
113    public void visitToken(DetailAST ast) {
114        visitClassDef(ast);
115    }
116
117    /**
118     * Checks class definition.
119     * @param ast class definition for check.
120     */
121    private void visitClassDef(DetailAST ast) {
122        final String className =
123            ast.findFirstToken(TokenTypes.IDENT).getText();
124        if (isAbstract(ast)) {
125            // if class has abstract modifier
126            if (!ignoreName && !isMatchingClassName(className)) {
127                log(ast.getLineNo(), ast.getColumnNo(),
128                    MSG_ILLEGAL_ABSTRACT_CLASS_NAME, className, format);
129            }
130        }
131        else if (!ignoreModifier && isMatchingClassName(className)) {
132            log(ast.getLineNo(), ast.getColumnNo(),
133                MSG_NO_ABSTRACT_CLASS_MODIFIER, className);
134        }
135    }
136
137    /**
138     * @param ast class definition for check.
139     * @return true if a given class declared as abstract.
140     */
141    private static boolean isAbstract(DetailAST ast) {
142        final DetailAST abstractAST = ast.findFirstToken(TokenTypes.MODIFIERS)
143            .findFirstToken(TokenTypes.ABSTRACT);
144
145        return abstractAST != null;
146    }
147
148    /**
149     * @param className class name for check.
150     * @return true if class name matches format of abstract class names.
151     */
152    private boolean isMatchingClassName(String className) {
153        return regexp.matcher(className).find();
154    }
155}