JavadocTypeCheck.java
///////////////////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code and other text files for adherence to a set of rules.
// Copyright (C) 2001-2022 the original author or authors.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
///////////////////////////////////////////////////////////////////////////////////////////////
package com.puppycrawl.tools.checkstyle.checks.javadoc;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import com.puppycrawl.tools.checkstyle.StatelessCheck;
import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
import com.puppycrawl.tools.checkstyle.api.DetailAST;
import com.puppycrawl.tools.checkstyle.api.FileContents;
import com.puppycrawl.tools.checkstyle.api.Scope;
import com.puppycrawl.tools.checkstyle.api.TextBlock;
import com.puppycrawl.tools.checkstyle.api.TokenTypes;
import com.puppycrawl.tools.checkstyle.utils.AnnotationUtil;
import com.puppycrawl.tools.checkstyle.utils.CheckUtil;
import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
import com.puppycrawl.tools.checkstyle.utils.JavadocUtil;
import com.puppycrawl.tools.checkstyle.utils.ScopeUtil;
import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
/**
* <p>
* Checks the Javadoc comments for type definitions. By default, does
* not check for author or version tags. The scope to verify is specified using the {@code Scope}
* class and defaults to {@code Scope.PRIVATE}. To verify another scope, set property
* scope to one of the {@code Scope} constants. To define the format for an author
* tag or a version tag, set property authorFormat or versionFormat respectively to a
* <a href="https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">
* pattern</a>.
* </p>
* <p>
* Does not perform checks for author and version tags for inner classes,
* as they should be redundant because of outer class.
* </p>
* <p>
* Error messages about type parameters and record components for which no param tags are present
* can be suppressed by defining property {@code allowMissingParamTags}.
* </p>
* <ul>
* <li>
* Property {@code scope} - Specify the visibility scope where Javadoc comments are checked.
* Type is {@code com.puppycrawl.tools.checkstyle.api.Scope}.
* Default value is {@code private}.
* </li>
* <li>
* Property {@code excludeScope} - Specify the visibility scope where Javadoc
* comments are not checked.
* Type is {@code com.puppycrawl.tools.checkstyle.api.Scope}.
* Default value is {@code null}.
* </li>
* <li>
* Property {@code authorFormat} - Specify the pattern for {@code @author} tag.
* Type is {@code java.util.regex.Pattern}.
* Default value is {@code null}.
* </li>
* <li>
* Property {@code versionFormat} - Specify the pattern for {@code @version} tag.
* Type is {@code java.util.regex.Pattern}.
* Default value is {@code null}.
* </li>
* <li>
* Property {@code allowMissingParamTags} - Control whether to ignore violations
* when a class has type parameters but does not have matching param tags in the Javadoc.
* Type is {@code boolean}.
* Default value is {@code false}.
* </li>
* <li>
* Property {@code allowUnknownTags} - Control whether to ignore violations when
* a Javadoc tag is not recognised.
* Type is {@code boolean}.
* Default value is {@code false}.
* </li>
* <li>
* Property {@code allowedAnnotations} - Specify annotations that allow
* missed documentation. Only short names are allowed, e.g. {@code Generated}.
* Type is {@code java.lang.String[]}.
* Default value is {@code Generated}.
* </li>
* <li>
* Property {@code tokens} - tokens to check
* Type is {@code java.lang.String[]}.
* Validation type is {@code tokenSet}.
* Default value is:
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#INTERFACE_DEF">
* INTERFACE_DEF</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#CLASS_DEF">
* CLASS_DEF</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#ENUM_DEF">
* ENUM_DEF</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#ANNOTATION_DEF">
* ANNOTATION_DEF</a>,
* <a href="https://checkstyle.org/apidocs/com/puppycrawl/tools/checkstyle/api/TokenTypes.html#RECORD_DEF">
* RECORD_DEF</a>.
* </li>
* </ul>
* <p>
* To configure the default check:
* </p>
* <pre>
* <module name="JavadocType"/>
* </pre>
* <p>
* To configure the check for {@code public} scope:
* </p>
* <pre>
* <module name="JavadocType">
* <property name="scope" value="public"/>
* </module>
* </pre>
* <p>
* To configure the check for an {@code @author} tag:
* </p>
* <pre>
* <module name="JavadocType">
* <property name="authorFormat" value="\S"/>
* </module>
* </pre>
* <p>
* To configure the check for a CVS revision version tag:
* </p>
* <pre>
* <module name="JavadocType">
* <property name="versionFormat" value="\$Revision.*\$"/>
* </module>
* </pre>
* <p>
* To configure the check for {@code private} classes only:
* </p>
* <pre>
* <module name="JavadocType">
* <property name="scope" value="private"/>
* <property name="excludeScope" value="package"/>
* </module>
* </pre>
* <p>
* Example that allows missing comments for classes annotated with
* {@code @SpringBootApplication} and {@code @Configuration}:
* </p>
* <pre>
* @SpringBootApplication // no violations about missing comment on class
* public class Application {}
*
* @Configuration // no violations about missing comment on class
* class DatabaseConfiguration {}
* </pre>
* <p>
* Use following configuration:
* </p>
* <pre>
* <module name="JavadocType">
* <property name="allowedAnnotations" value="SpringBootApplication,Configuration"/>
* </module>
* </pre>
* <p>
* Parent is {@code com.puppycrawl.tools.checkstyle.TreeWalker}
* </p>
* <p>
* Violation Message Keys:
* </p>
* <ul>
* <li>
* {@code javadoc.unknownTag}
* </li>
* <li>
* {@code javadoc.unusedTag}
* </li>
* <li>
* {@code javadoc.unusedTagGeneral}
* </li>
* <li>
* {@code type.missingTag}
* </li>
* <li>
* {@code type.tagFormat}
* </li>
* </ul>
*
* @since 3.0
*
*/
@StatelessCheck
public class JavadocTypeCheck
extends AbstractCheck {
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_UNKNOWN_TAG = "javadoc.unknownTag";
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_TAG_FORMAT = "type.tagFormat";
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_MISSING_TAG = "type.missingTag";
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_UNUSED_TAG = "javadoc.unusedTag";
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_UNUSED_TAG_GENERAL = "javadoc.unusedTagGeneral";
/** Open angle bracket literal. */
private static final String OPEN_ANGLE_BRACKET = "<";
/** Close angle bracket literal. */
private static final String CLOSE_ANGLE_BRACKET = ">";
/** Space literal. */
private static final String SPACE = " ";
/** Pattern to match type name within angle brackets in javadoc param tag. */
private static final Pattern TYPE_NAME_IN_JAVADOC_TAG =
Pattern.compile("\\s*<([^>]+)>.*");
/** Pattern to split type name field in javadoc param tag. */
private static final Pattern TYPE_NAME_IN_JAVADOC_TAG_SPLITTER =
Pattern.compile("\\s+");
/** Specify the visibility scope where Javadoc comments are checked. */
private Scope scope = Scope.PRIVATE;
/** Specify the visibility scope where Javadoc comments are not checked. */
private Scope excludeScope;
/** Specify the pattern for {@code @author} tag. */
private Pattern authorFormat;
/** Specify the pattern for {@code @version} tag. */
private Pattern versionFormat;
/**
* Control whether to ignore violations when a class has type parameters but
* does not have matching param tags in the Javadoc.
*/
private boolean allowMissingParamTags;
/** Control whether to ignore violations when a Javadoc tag is not recognised. */
private boolean allowUnknownTags;
/**
* Specify annotations that allow missed documentation.
* Only short names are allowed, e.g. {@code Generated}.
*/
private Set<String> allowedAnnotations = Set.of("Generated");
/**
* Setter to specify the visibility scope where Javadoc comments are checked.
*
* @param scope a scope.
*/
public void setScope(Scope scope) {
this.scope = scope;
}
/**
* Setter to specify the visibility scope where Javadoc comments are not checked.
*
* @param excludeScope a scope.
*/
public void setExcludeScope(Scope excludeScope) {
this.excludeScope = excludeScope;
}
/**
* Setter to specify the pattern for {@code @author} tag.
*
* @param pattern a pattern.
*/
public void setAuthorFormat(Pattern pattern) {
authorFormat = pattern;
}
/**
* Setter to specify the pattern for {@code @version} tag.
*
* @param pattern a pattern.
*/
public void setVersionFormat(Pattern pattern) {
versionFormat = pattern;
}
/**
* Setter to control whether to ignore violations when a class has type parameters but
* does not have matching param tags in the Javadoc.
*
* @param flag a {@code Boolean} value
*/
public void setAllowMissingParamTags(boolean flag) {
allowMissingParamTags = flag;
}
/**
* Setter to control whether to ignore violations when a Javadoc tag is not recognised.
*
* @param flag a {@code Boolean} value
*/
public void setAllowUnknownTags(boolean flag) {
allowUnknownTags = flag;
}
/**
* Setter to specify annotations that allow missed documentation.
* Only short names are allowed, e.g. {@code Generated}.
*
* @param userAnnotations user's value.
*/
public void setAllowedAnnotations(String... userAnnotations) {
allowedAnnotations = Set.of(userAnnotations);
}
@Override
public int[] getDefaultTokens() {
return getAcceptableTokens();
}
@Override
public int[] getAcceptableTokens() {
return new int[] {
TokenTypes.INTERFACE_DEF,
TokenTypes.CLASS_DEF,
TokenTypes.ENUM_DEF,
TokenTypes.ANNOTATION_DEF,
TokenTypes.RECORD_DEF,
};
}
@Override
public int[] getRequiredTokens() {
return CommonUtil.EMPTY_INT_ARRAY;
}
// suppress deprecation until https://github.com/checkstyle/checkstyle/issues/11166
@SuppressWarnings("deprecation")
@Override
public void visitToken(DetailAST ast) {
if (shouldCheck(ast)) {
final FileContents contents = getFileContents();
final int lineNo = ast.getLineNo();
final TextBlock textBlock = contents.getJavadocBefore(lineNo);
if (textBlock != null) {
final List<JavadocTag> tags = getJavadocTags(textBlock);
if (ScopeUtil.isOuterMostType(ast)) {
// don't check author/version for inner classes
checkTag(ast, tags, JavadocTagInfo.AUTHOR.getName(),
authorFormat);
checkTag(ast, tags, JavadocTagInfo.VERSION.getName(),
versionFormat);
}
final List<String> typeParamNames =
CheckUtil.getTypeParameterNames(ast);
final List<String> recordComponentNames =
getRecordComponentNames(ast);
if (!allowMissingParamTags) {
typeParamNames.forEach(typeParamName -> {
checkTypeParamTag(ast, tags, typeParamName);
});
recordComponentNames.forEach(componentName -> {
checkComponentParamTag(ast, tags, componentName);
});
}
checkUnusedParamTags(tags, typeParamNames, recordComponentNames);
}
}
}
/**
* Whether we should check this node.
*
* @param ast a given node.
* @return whether we should check a given node.
*/
private boolean shouldCheck(DetailAST ast) {
final Scope customScope = ScopeUtil.getScope(ast);
final Scope surroundingScope = ScopeUtil.getSurroundingScope(ast);
return customScope.isIn(scope)
&& (surroundingScope == null || surroundingScope.isIn(scope))
&& (excludeScope == null
|| !customScope.isIn(excludeScope)
|| surroundingScope != null
&& !surroundingScope.isIn(excludeScope))
&& !AnnotationUtil.containsAnnotation(ast, allowedAnnotations);
}
/**
* Gets all standalone tags from a given javadoc.
*
* @param textBlock the Javadoc comment to process.
* @return all standalone tags from the given javadoc.
*/
private List<JavadocTag> getJavadocTags(TextBlock textBlock) {
final JavadocTags tags = JavadocUtil.getJavadocTags(textBlock,
JavadocUtil.JavadocTagType.BLOCK);
if (!allowUnknownTags) {
for (final InvalidJavadocTag tag : tags.getInvalidTags()) {
log(tag.getLine(), tag.getCol(), MSG_UNKNOWN_TAG,
tag.getName());
}
}
return tags.getValidTags();
}
/**
* Verifies that a type definition has a required tag.
*
* @param ast the AST node for the type definition.
* @param tags tags from the Javadoc comment for the type definition.
* @param tagName the required tag name.
* @param formatPattern regexp for the tag value.
*/
private void checkTag(DetailAST ast, List<JavadocTag> tags, String tagName,
Pattern formatPattern) {
if (formatPattern != null) {
boolean hasTag = false;
final String tagPrefix = "@";
for (final JavadocTag tag :tags) {
if (tag.getTagName().equals(tagName)) {
hasTag = true;
if (!formatPattern.matcher(tag.getFirstArg()).find()) {
log(ast, MSG_TAG_FORMAT, tagPrefix + tagName, formatPattern.pattern());
}
}
}
if (!hasTag) {
log(ast, MSG_MISSING_TAG, tagPrefix + tagName);
}
}
}
/**
* Verifies that a record definition has the specified param tag for
* the specified record component name.
*
* @param ast the AST node for the record definition.
* @param tags tags from the Javadoc comment for the record definition.
* @param recordComponentName the name of the type parameter
*/
private void checkComponentParamTag(DetailAST ast,
List<JavadocTag> tags,
String recordComponentName) {
final boolean found = tags
.stream()
.filter(JavadocTag::isParamTag)
.anyMatch(tag -> tag.getFirstArg().indexOf(recordComponentName) == 0);
if (!found) {
log(ast, MSG_MISSING_TAG, JavadocTagInfo.PARAM.getText()
+ SPACE + recordComponentName);
}
}
/**
* Verifies that a type definition has the specified param tag for
* the specified type parameter name.
*
* @param ast the AST node for the type definition.
* @param tags tags from the Javadoc comment for the type definition.
* @param typeParamName the name of the type parameter
*/
private void checkTypeParamTag(DetailAST ast,
List<JavadocTag> tags, String typeParamName) {
final String typeParamNameWithBrackets =
OPEN_ANGLE_BRACKET + typeParamName + CLOSE_ANGLE_BRACKET;
final boolean found = tags
.stream()
.filter(JavadocTag::isParamTag)
.anyMatch(tag -> tag.getFirstArg().indexOf(typeParamNameWithBrackets) == 0);
if (!found) {
log(ast, MSG_MISSING_TAG, JavadocTagInfo.PARAM.getText()
+ SPACE + typeParamNameWithBrackets);
}
}
/**
* Checks for unused param tags for type parameters and record components.
*
* @param tags tags from the Javadoc comment for the type definition
* @param typeParamNames names of type parameters
* @param recordComponentNames record component names in this definition
*/
private void checkUnusedParamTags(
List<JavadocTag> tags,
List<String> typeParamNames,
List<String> recordComponentNames) {
for (final JavadocTag tag: tags) {
if (tag.isParamTag()) {
final String paramName = extractParamNameFromTag(tag);
final boolean found = typeParamNames.contains(paramName)
|| recordComponentNames.contains(paramName);
if (!found) {
final String actualParamName =
TYPE_NAME_IN_JAVADOC_TAG_SPLITTER.split(tag.getFirstArg())[0];
log(tag.getLineNo(), tag.getColumnNo(),
MSG_UNUSED_TAG,
JavadocTagInfo.PARAM.getText(), actualParamName);
}
}
}
}
/**
* Extracts parameter name from tag.
*
* @param tag javadoc tag to extract parameter name
* @return extracts type parameter name from tag
*/
private static String extractParamNameFromTag(JavadocTag tag) {
final String typeParamName;
final Matcher matchInAngleBrackets =
TYPE_NAME_IN_JAVADOC_TAG.matcher(tag.getFirstArg());
if (matchInAngleBrackets.find()) {
typeParamName = matchInAngleBrackets.group(1).trim();
}
else {
typeParamName = TYPE_NAME_IN_JAVADOC_TAG_SPLITTER.split(tag.getFirstArg())[0];
}
return typeParamName;
}
/**
* Collects the record components in a record definition.
*
* @param node the possible record definition ast.
* @return the record components in this record definition.
*/
private static List<String> getRecordComponentNames(DetailAST node) {
final DetailAST components = node.findFirstToken(TokenTypes.RECORD_COMPONENTS);
final List<String> componentList = new ArrayList<>();
if (components != null) {
TokenUtil.forEachChild(components,
TokenTypes.RECORD_COMPONENT_DEF, component -> {
final DetailAST ident = component.findFirstToken(TokenTypes.IDENT);
componentList.add(ident.getText());
});
}
return componentList;
}
}