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.javadoc;
021
022import java.util.List;
023import java.util.regex.Matcher;
024import java.util.regex.Pattern;
025
026import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
027import com.puppycrawl.tools.checkstyle.api.DetailAST;
028import com.puppycrawl.tools.checkstyle.api.FileContents;
029import com.puppycrawl.tools.checkstyle.api.Scope;
030import com.puppycrawl.tools.checkstyle.api.TextBlock;
031import com.puppycrawl.tools.checkstyle.api.TokenTypes;
032import com.puppycrawl.tools.checkstyle.utils.CheckUtils;
033import com.puppycrawl.tools.checkstyle.utils.CommonUtils;
034import com.puppycrawl.tools.checkstyle.utils.JavadocUtils;
035import com.puppycrawl.tools.checkstyle.utils.ScopeUtils;
036
037/**
038 * Checks the Javadoc of a type.
039 *
040 * <p>Does not perform checks for author and version tags for inner classes, as
041 * they should be redundant because of outer class.
042 *
043 * @author Oliver Burn
044 * @author Michael Tamm
045 */
046public class JavadocTypeCheck
047    extends AbstractCheck {
048
049    /**
050     * A key is pointing to the warning message text in "messages.properties"
051     * file.
052     */
053    public static final String MSG_JAVADOC_MISSING = "javadoc.missing";
054
055    /**
056     * A key is pointing to the warning message text in "messages.properties"
057     * file.
058     */
059    public static final String MSG_UNKNOWN_TAG = "javadoc.unknownTag";
060
061    /**
062     * A key is pointing to the warning message text in "messages.properties"
063     * file.
064     */
065    public static final String MSG_TAG_FORMAT = "type.tagFormat";
066
067    /**
068     * A key is pointing to the warning message text in "messages.properties"
069     * file.
070     */
071    public static final String MSG_MISSING_TAG = "type.missingTag";
072
073    /**
074     * A key is pointing to the warning message text in "messages.properties"
075     * file.
076     */
077    public static final String MSG_UNUSED_TAG = "javadoc.unusedTag";
078
079    /**
080     * A key is pointing to the warning message text in "messages.properties"
081     * file.
082     */
083    public static final String MSG_UNUSED_TAG_GENERAL = "javadoc.unusedTagGeneral";
084
085    /** Open angle bracket literal. */
086    private static final String OPEN_ANGLE_BRACKET = "<";
087
088    /** Close angle bracket literal. */
089    private static final String CLOSE_ANGLE_BRACKET = ">";
090
091    /** Pattern to match type name within angle brackets in javadoc param tag. */
092    private static final Pattern TYPE_NAME_IN_JAVADOC_TAG =
093            Pattern.compile("\\s*<([^>]+)>.*");
094
095    /** Pattern to split type name field in javadoc param tag. */
096    private static final Pattern TYPE_NAME_IN_JAVADOC_TAG_SPLITTER =
097            Pattern.compile("\\s+");
098
099    /** The scope to check for. */
100    private Scope scope = Scope.PRIVATE;
101    /** The visibility scope where Javadoc comments shouldn't be checked. **/
102    private Scope excludeScope;
103    /** Compiled regexp to match author tag content. **/
104    private Pattern authorFormatPattern;
105    /** Compiled regexp to match version tag content. **/
106    private Pattern versionFormatPattern;
107    /** Regexp to match author tag content. */
108    private String authorFormat;
109    /** Regexp to match version tag content. */
110    private String versionFormat;
111    /**
112     * Controls whether to ignore errors when a method has type parameters but
113     * does not have matching param tags in the javadoc. Defaults to false.
114     */
115    private boolean allowMissingParamTags;
116    /** Controls whether to flag errors for unknown tags. Defaults to false. */
117    private boolean allowUnknownTags;
118
119    /**
120     * Sets the scope to check.
121     * @param from string to set scope from
122     */
123    public void setScope(String from) {
124        scope = Scope.getInstance(from);
125    }
126
127    /**
128     * Set the excludeScope.
129     * @param excludeScope a {@code String} value
130     */
131    public void setExcludeScope(String excludeScope) {
132        this.excludeScope = Scope.getInstance(excludeScope);
133    }
134
135    /**
136     * Set the author tag pattern.
137     * @param format a {@code String} value
138     */
139    public void setAuthorFormat(String format) {
140        authorFormat = format;
141        authorFormatPattern = CommonUtils.createPattern(format);
142    }
143
144    /**
145     * Set the version format pattern.
146     * @param format a {@code String} value
147     */
148    public void setVersionFormat(String format) {
149        versionFormat = format;
150        versionFormatPattern = CommonUtils.createPattern(format);
151    }
152
153    /**
154     * Controls whether to allow a type which has type parameters to
155     * omit matching param tags in the javadoc. Defaults to false.
156     *
157     * @param flag a {@code Boolean} value
158     */
159    public void setAllowMissingParamTags(boolean flag) {
160        allowMissingParamTags = flag;
161    }
162
163    /**
164     * Controls whether to flag errors for unknown tags. Defaults to false.
165     * @param flag a {@code Boolean} value
166     */
167    public void setAllowUnknownTags(boolean flag) {
168        allowUnknownTags = flag;
169    }
170
171    @Override
172    public int[] getDefaultTokens() {
173        return getAcceptableTokens();
174    }
175
176    @Override
177    public int[] getAcceptableTokens() {
178        return new int[] {
179            TokenTypes.INTERFACE_DEF,
180            TokenTypes.CLASS_DEF,
181            TokenTypes.ENUM_DEF,
182            TokenTypes.ANNOTATION_DEF,
183        };
184    }
185
186    @Override
187    public int[] getRequiredTokens() {
188        return CommonUtils.EMPTY_INT_ARRAY;
189    }
190
191    @Override
192    public void visitToken(DetailAST ast) {
193        if (shouldCheck(ast)) {
194            final FileContents contents = getFileContents();
195            final int lineNo = ast.getLineNo();
196            final TextBlock textBlock = contents.getJavadocBefore(lineNo);
197            if (textBlock == null) {
198                log(lineNo, MSG_JAVADOC_MISSING);
199            }
200            else {
201                final List<JavadocTag> tags = getJavadocTags(textBlock);
202                if (ScopeUtils.isOuterMostType(ast)) {
203                    // don't check author/version for inner classes
204                    checkTag(lineNo, tags, JavadocTagInfo.AUTHOR.getName(),
205                            authorFormatPattern, authorFormat);
206                    checkTag(lineNo, tags, JavadocTagInfo.VERSION.getName(),
207                            versionFormatPattern, versionFormat);
208                }
209
210                final List<String> typeParamNames =
211                    CheckUtils.getTypeParameterNames(ast);
212
213                if (!allowMissingParamTags) {
214                    //Check type parameters that should exist, do
215                    for (final String typeParamName : typeParamNames) {
216                        checkTypeParamTag(
217                            lineNo, tags, typeParamName);
218                    }
219                }
220
221                checkUnusedTypeParamTags(tags, typeParamNames);
222            }
223        }
224    }
225
226    /**
227     * Whether we should check this node.
228     * @param ast a given node.
229     * @return whether we should check a given node.
230     */
231    private boolean shouldCheck(final DetailAST ast) {
232        final DetailAST mods = ast.findFirstToken(TokenTypes.MODIFIERS);
233        final Scope declaredScope = ScopeUtils.getScopeFromMods(mods);
234        final Scope customScope;
235
236        if (ScopeUtils.isInInterfaceOrAnnotationBlock(ast)) {
237            customScope = Scope.PUBLIC;
238        }
239        else {
240            customScope = declaredScope;
241        }
242        final Scope surroundingScope = ScopeUtils.getSurroundingScope(ast);
243
244        return customScope.isIn(scope)
245            && (surroundingScope == null || surroundingScope.isIn(scope))
246            && (excludeScope == null
247                || !customScope.isIn(excludeScope)
248                || surroundingScope != null
249                && !surroundingScope.isIn(excludeScope));
250    }
251
252    /**
253     * Gets all standalone tags from a given javadoc.
254     * @param textBlock the Javadoc comment to process.
255     * @return all standalone tags from the given javadoc.
256     */
257    private List<JavadocTag> getJavadocTags(TextBlock textBlock) {
258        final JavadocTags tags = JavadocUtils.getJavadocTags(textBlock,
259            JavadocUtils.JavadocTagType.BLOCK);
260        if (!allowUnknownTags) {
261            for (final InvalidJavadocTag tag : tags.getInvalidTags()) {
262                log(tag.getLine(), tag.getCol(), MSG_UNKNOWN_TAG,
263                    tag.getName());
264            }
265        }
266        return tags.getValidTags();
267    }
268
269    /**
270     * Verifies that a type definition has a required tag.
271     * @param lineNo the line number for the type definition.
272     * @param tags tags from the Javadoc comment for the type definition.
273     * @param tagName the required tag name.
274     * @param formatPattern regexp for the tag value.
275     * @param format pattern for the tag value.
276     */
277    private void checkTag(int lineNo, List<JavadocTag> tags, String tagName,
278                          Pattern formatPattern, String format) {
279        if (formatPattern != null) {
280            int tagCount = 0;
281            final String tagPrefix = "@";
282            for (int i = tags.size() - 1; i >= 0; i--) {
283                final JavadocTag tag = tags.get(i);
284                if (tag.getTagName().equals(tagName)) {
285                    tagCount++;
286                    if (!formatPattern.matcher(tag.getFirstArg()).find()) {
287                        log(lineNo, MSG_TAG_FORMAT, tagPrefix + tagName, format);
288                    }
289                }
290            }
291            if (tagCount == 0) {
292                log(lineNo, MSG_MISSING_TAG, tagPrefix + tagName);
293            }
294        }
295    }
296
297    /**
298     * Verifies that a type definition has the specified param tag for
299     * the specified type parameter name.
300     * @param lineNo the line number for the type definition.
301     * @param tags tags from the Javadoc comment for the type definition.
302     * @param typeParamName the name of the type parameter
303     */
304    private void checkTypeParamTag(final int lineNo,
305            final List<JavadocTag> tags, final String typeParamName) {
306        boolean found = false;
307        for (int i = tags.size() - 1; i >= 0; i--) {
308            final JavadocTag tag = tags.get(i);
309            if (tag.isParamTag()
310                && tag.getFirstArg().indexOf(OPEN_ANGLE_BRACKET
311                        + typeParamName + CLOSE_ANGLE_BRACKET) == 0) {
312                found = true;
313            }
314        }
315        if (!found) {
316            log(lineNo, MSG_MISSING_TAG, JavadocTagInfo.PARAM.getText()
317                + " " + OPEN_ANGLE_BRACKET + typeParamName + CLOSE_ANGLE_BRACKET);
318        }
319    }
320
321    /**
322     * Checks for unused param tags for type parameters.
323     * @param tags tags from the Javadoc comment for the type definition.
324     * @param typeParamNames names of type parameters
325     */
326    private void checkUnusedTypeParamTags(
327        final List<JavadocTag> tags,
328        final List<String> typeParamNames) {
329        for (int i = tags.size() - 1; i >= 0; i--) {
330            final JavadocTag tag = tags.get(i);
331            if (tag.isParamTag()) {
332
333                final String typeParamName = extractTypeParamNameFromTag(tag);
334
335                if (!typeParamNames.contains(typeParamName)) {
336                    log(tag.getLineNo(), tag.getColumnNo(),
337                            MSG_UNUSED_TAG,
338                            JavadocTagInfo.PARAM.getText(),
339                            OPEN_ANGLE_BRACKET + typeParamName + CLOSE_ANGLE_BRACKET);
340                }
341            }
342        }
343    }
344
345    /**
346     * Extracts type parameter name from tag.
347     * @param tag javadoc tag to extract parameter name
348     * @return extracts type parameter name from tag
349     */
350    private static String extractTypeParamNameFromTag(JavadocTag tag) {
351        final String typeParamName;
352        final Matcher matchInAngleBrackets =
353                TYPE_NAME_IN_JAVADOC_TAG.matcher(tag.getFirstArg());
354        if (matchInAngleBrackets.find()) {
355            typeParamName = matchInAngleBrackets.group(1).trim();
356        }
357        else {
358            typeParamName = TYPE_NAME_IN_JAVADOC_TAG_SPLITTER.split(tag.getFirstArg())[0];
359        }
360        return typeParamName;
361    }
362}