Source code

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 org.apache.commons.lang3.ArrayUtils;
027
028import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
029import com.puppycrawl.tools.checkstyle.api.DetailAST;
030import com.puppycrawl.tools.checkstyle.api.FileContents;
031import com.puppycrawl.tools.checkstyle.api.Scope;
032import com.puppycrawl.tools.checkstyle.api.TextBlock;
033import com.puppycrawl.tools.checkstyle.api.TokenTypes;
034import com.puppycrawl.tools.checkstyle.utils.CheckUtils;
035import com.puppycrawl.tools.checkstyle.utils.CommonUtils;
036import com.puppycrawl.tools.checkstyle.utils.JavadocUtils;
037import com.puppycrawl.tools.checkstyle.utils.ScopeUtils;
038
039/**
040 * Checks the Javadoc of a type.
041 *
042 * <p>Does not perform checks for author and version tags for inner classes, as
043 * they should be redundant because of outer class.
044 *
045 * @author Oliver Burn
046 * @author Michael Tamm
047 */
048public class JavadocTypeCheck
049    extends AbstractCheck {
050
051    /**
052     * A key is pointing to the warning message text in "messages.properties"
053     * file.
054     */
055    public static final String MSG_JAVADOC_MISSING = "javadoc.missing";
056
057    /**
058     * A key is pointing to the warning message text in "messages.properties"
059     * file.
060     */
061    public static final String MSG_UNKNOWN_TAG = "javadoc.unknownTag";
062
063    /**
064     * A key is pointing to the warning message text in "messages.properties"
065     * file.
066     */
067    public static final String MSG_TAG_FORMAT = "type.tagFormat";
068
069    /**
070     * A key is pointing to the warning message text in "messages.properties"
071     * file.
072     */
073    public static final String MSG_MISSING_TAG = "type.missingTag";
074
075    /**
076     * A key is pointing to the warning message text in "messages.properties"
077     * file.
078     */
079    public static final String MSG_UNUSED_TAG = "javadoc.unusedTag";
080
081    /**
082     * A key is pointing to the warning message text in "messages.properties"
083     * file.
084     */
085    public static final String MSG_UNUSED_TAG_GENERAL = "javadoc.unusedTagGeneral";
086
087    /** Open angle bracket literal. */
088    private static final String OPEN_ANGLE_BRACKET = "<";
089
090    /** Close angle bracket literal. */
091    private static final String CLOSE_ANGLE_BRACKET = ">";
092
093    /** Pattern to match type name within angle brackets in javadoc param tag. */
094    private static final Pattern TYPE_NAME_IN_JAVADOC_TAG =
095            Pattern.compile("\\s*<([^>]+)>.*");
096
097    /** Pattern to split type name field in javadoc param tag. */
098    private static final Pattern TYPE_NAME_IN_JAVADOC_TAG_SPLITTER =
099            Pattern.compile("\\s+");
100
101    /** The scope to check for. */
102    private Scope scope = Scope.PRIVATE;
103    /** The visibility scope where Javadoc comments shouldn't be checked. **/
104    private Scope excludeScope;
105    /** Compiled regexp to match author tag content. **/
106    private Pattern authorFormatPattern;
107    /** Compiled regexp to match version tag content. **/
108    private Pattern versionFormatPattern;
109    /** Regexp to match author tag content. */
110    private String authorFormat;
111    /** Regexp to match version tag content. */
112    private String versionFormat;
113    /**
114     * Controls whether to ignore errors when a method has type parameters but
115     * does not have matching param tags in the javadoc. Defaults to false.
116     */
117    private boolean allowMissingParamTags;
118    /** Controls whether to flag errors for unknown tags. Defaults to false. */
119    private boolean allowUnknownTags;
120
121    /**
122     * Sets the scope to check.
123     * @param from string to set scope from
124     */
125    public void setScope(String from) {
126        scope = Scope.getInstance(from);
127    }
128
129    /**
130     * Set the excludeScope.
131     * @param excludeScope a {@code String} value
132     */
133    public void setExcludeScope(String excludeScope) {
134        this.excludeScope = Scope.getInstance(excludeScope);
135    }
136
137    /**
138     * Set the author tag pattern.
139     * @param format a {@code String} value
140     */
141    public void setAuthorFormat(String format) {
142        authorFormat = format;
143        authorFormatPattern = CommonUtils.createPattern(format);
144    }
145
146    /**
147     * Set the version format pattern.
148     * @param format a {@code String} value
149     */
150    public void setVersionFormat(String format) {
151        versionFormat = format;
152        versionFormatPattern = CommonUtils.createPattern(format);
153    }
154
155    /**
156     * Controls whether to allow a type which has type parameters to
157     * omit matching param tags in the javadoc. Defaults to false.
158     *
159     * @param flag a {@code Boolean} value
160     */
161    public void setAllowMissingParamTags(boolean flag) {
162        allowMissingParamTags = flag;
163    }
164
165    /**
166     * Controls whether to flag errors for unknown tags. Defaults to false.
167     * @param flag a {@code Boolean} value
168     */
169    public void setAllowUnknownTags(boolean flag) {
170        allowUnknownTags = flag;
171    }
172
173    @Override
174    public int[] getDefaultTokens() {
175        return getAcceptableTokens();
176    }
177
178    @Override
179    public int[] getAcceptableTokens() {
180        return new int[] {
181            TokenTypes.INTERFACE_DEF,
182            TokenTypes.CLASS_DEF,
183            TokenTypes.ENUM_DEF,
184            TokenTypes.ANNOTATION_DEF,
185        };
186    }
187
188    @Override
189    public int[] getRequiredTokens() {
190        return ArrayUtils.EMPTY_INT_ARRAY;
191    }
192
193    @Override
194    public void visitToken(DetailAST ast) {
195        if (shouldCheck(ast)) {
196            final FileContents contents = getFileContents();
197            final int lineNo = ast.getLineNo();
198            final TextBlock textBlock = contents.getJavadocBefore(lineNo);
199            if (textBlock == null) {
200                log(lineNo, MSG_JAVADOC_MISSING);
201            }
202            else {
203                final List<JavadocTag> tags = getJavadocTags(textBlock);
204                if (ScopeUtils.isOuterMostType(ast)) {
205                    // don't check author/version for inner classes
206                    checkTag(lineNo, tags, JavadocTagInfo.AUTHOR.getName(),
207                            authorFormatPattern, authorFormat);
208                    checkTag(lineNo, tags, JavadocTagInfo.VERSION.getName(),
209                            versionFormatPattern, versionFormat);
210                }
211
212                final List<String> typeParamNames =
213                    CheckUtils.getTypeParameterNames(ast);
214
215                if (!allowMissingParamTags) {
216                    //Check type parameters that should exist, do
217                    for (final String typeParamName : typeParamNames) {
218                        checkTypeParamTag(
219                            lineNo, tags, typeParamName);
220                    }
221                }
222
223                checkUnusedTypeParamTags(tags, typeParamNames);
224            }
225        }
226    }
227
228    /**
229     * Whether we should check this node.
230     * @param ast a given node.
231     * @return whether we should check a given node.
232     */
233    private boolean shouldCheck(final DetailAST ast) {
234        final DetailAST mods = ast.findFirstToken(TokenTypes.MODIFIERS);
235        final Scope declaredScope = ScopeUtils.getScopeFromMods(mods);
236        final Scope customScope;
237
238        if (ScopeUtils.isInInterfaceOrAnnotationBlock(ast)) {
239            customScope = Scope.PUBLIC;
240        }
241        else {
242            customScope = declaredScope;
243        }
244        final Scope surroundingScope = ScopeUtils.getSurroundingScope(ast);
245
246        return customScope.isIn(scope)
247            && (surroundingScope == null || surroundingScope.isIn(scope))
248            && (excludeScope == null
249                || !customScope.isIn(excludeScope)
250                || surroundingScope != null
251                && !surroundingScope.isIn(excludeScope));
252    }
253
254    /**
255     * Gets all standalone tags from a given javadoc.
256     * @param textBlock the Javadoc comment to process.
257     * @return all standalone tags from the given javadoc.
258     */
259    private List<JavadocTag> getJavadocTags(TextBlock textBlock) {
260        final JavadocTags tags = JavadocUtils.getJavadocTags(textBlock,
261            JavadocUtils.JavadocTagType.BLOCK);
262        if (!allowUnknownTags) {
263            for (final InvalidJavadocTag tag : tags.getInvalidTags()) {
264                log(tag.getLine(), tag.getCol(), MSG_UNKNOWN_TAG,
265                    tag.getName());
266            }
267        }
268        return tags.getValidTags();
269    }
270
271    /**
272     * Verifies that a type definition has a required tag.
273     * @param lineNo the line number for the type definition.
274     * @param tags tags from the Javadoc comment for the type definition.
275     * @param tagName the required tag name.
276     * @param formatPattern regexp for the tag value.
277     * @param format pattern for the tag value.
278     */
279    private void checkTag(int lineNo, List<JavadocTag> tags, String tagName,
280                          Pattern formatPattern, String format) {
281        if (formatPattern == null) {
282            return;
283        }
284
285        int tagCount = 0;
286        final String tagPrefix = "@";
287        for (int i = tags.size() - 1; i >= 0; i--) {
288            final JavadocTag tag = tags.get(i);
289            if (tag.getTagName().equals(tagName)) {
290                tagCount++;
291                if (!formatPattern.matcher(tag.getFirstArg()).find()) {
292                    log(lineNo, MSG_TAG_FORMAT, tagPrefix + tagName, format);
293                }
294            }
295        }
296        if (tagCount == 0) {
297            log(lineNo, MSG_MISSING_TAG, tagPrefix + tagName);
298        }
299    }
300
301    /**
302     * Verifies that a type definition has the specified param tag for
303     * the specified type parameter name.
304     * @param lineNo the line number for the type definition.
305     * @param tags tags from the Javadoc comment for the type definition.
306     * @param typeParamName the name of the type parameter
307     */
308    private void checkTypeParamTag(final int lineNo,
309            final List<JavadocTag> tags, final String typeParamName) {
310        boolean found = false;
311        for (int i = tags.size() - 1; i >= 0; i--) {
312            final JavadocTag tag = tags.get(i);
313            if (tag.isParamTag()
314                && tag.getFirstArg().indexOf(OPEN_ANGLE_BRACKET
315                        + typeParamName + CLOSE_ANGLE_BRACKET) == 0) {
316                found = true;
317            }
318        }
319        if (!found) {
320            log(lineNo, MSG_MISSING_TAG, JavadocTagInfo.PARAM.getText()
321                + " " + OPEN_ANGLE_BRACKET + typeParamName + CLOSE_ANGLE_BRACKET);
322        }
323    }
324
325    /**
326     * Checks for unused param tags for type parameters.
327     * @param tags tags from the Javadoc comment for the type definition.
328     * @param typeParamNames names of type parameters
329     */
330    private void checkUnusedTypeParamTags(
331        final List<JavadocTag> tags,
332        final List<String> typeParamNames) {
333        for (int i = tags.size() - 1; i >= 0; i--) {
334            final JavadocTag tag = tags.get(i);
335            if (tag.isParamTag()) {
336
337                final String typeParamName = extractTypeParamNameFromTag(tag);
338
339                if (!typeParamNames.contains(typeParamName)) {
340                    log(tag.getLineNo(), tag.getColumnNo(),
341                            MSG_UNUSED_TAG,
342                            JavadocTagInfo.PARAM.getText(),
343                            OPEN_ANGLE_BRACKET + typeParamName + CLOSE_ANGLE_BRACKET);
344                }
345            }
346        }
347    }
348
349    /**
350     * Extracts type parameter name from tag.
351     * @param tag javadoc tag to extract parameter name
352     * @return extracts type parameter name from tag
353     */
354    private static String extractTypeParamNameFromTag(JavadocTag tag) {
355        final String typeParamName;
356        final Matcher matchInAngleBrackets =
357                TYPE_NAME_IN_JAVADOC_TAG.matcher(tag.getFirstArg());
358        if (matchInAngleBrackets.find()) {
359            typeParamName = matchInAngleBrackets.group(1).trim();
360        }
361        else {
362            typeParamName = TYPE_NAME_IN_JAVADOC_TAG_SPLITTER.split(tag.getFirstArg())[0];
363        }
364        return typeParamName;
365    }
366}