com.puppycrawl.tools.checkstyle.checks.javadoc.SummaryJavadocCheck Maven / Gradle / Ivy
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Checkstyle is a development tool to help programmers write Java code that adheres to a coding standard
////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2018 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.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import java.util.regex.Pattern;
import com.google.common.base.CharMatcher;
import com.puppycrawl.tools.checkstyle.api.DetailNode;
import com.puppycrawl.tools.checkstyle.api.JavadocTokenTypes;
import com.puppycrawl.tools.checkstyle.utils.CommonUtils;
import com.puppycrawl.tools.checkstyle.utils.JavadocUtils;
/**
*
* Checks that
* Javadoc summary sentence does not contain phrases that are not recommended to use.
* Check also violate javadoc that does not contain first sentence.
* By default Check validate that first sentence is not empty:
*
* <module name="SummaryJavadocCheck"/>
*
*
* To ensure that summary do not contain phrase like "This method returns",
* use following config:
*
*
* <module name="SummaryJavadocCheck">
* <property name="forbiddenSummaryFragments"
* value="^This method returns.*"/>
* </module>
*
*
* To specify period symbol at the end of first javadoc sentence - use following config:
*
*
* <module name="SummaryJavadocCheck">
* <property name="period"
* value="period"/>
* </module>
*
*
*
*/
public class SummaryJavadocCheck extends AbstractJavadocCheck {
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_SUMMARY_FIRST_SENTENCE = "summary.first.sentence";
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_SUMMARY_JAVADOC = "summary.javaDoc";
/**
* A key is pointing to the warning message text in "messages.properties"
* file.
*/
public static final String MSG_SUMMARY_JAVADOC_MISSING = "summary.javaDoc.missing";
/**
* This regexp is used to convert multiline javadoc to single line without stars.
*/
private static final Pattern JAVADOC_MULTILINE_TO_SINGLELINE_PATTERN =
Pattern.compile("\n[ ]+(\\*)|^[ ]+(\\*)");
/** Period literal. */
private static final String PERIOD = ".";
/** Set of allowed Tokens tags in summary java doc. */
private static final Set ALLOWED_TYPES = Collections.unmodifiableSet(
new HashSet<>(Arrays.asList(JavadocTokenTypes.TEXT,
JavadocTokenTypes.WS))
);
/** Regular expression for forbidden summary fragments. */
private Pattern forbiddenSummaryFragments = CommonUtils.createPattern("^$");
/** Period symbol at the end of first javadoc sentence. */
private String period = PERIOD;
/**
* Sets custom value of regular expression for forbidden summary fragments.
* @param pattern a pattern.
*/
public void setForbiddenSummaryFragments(Pattern pattern) {
forbiddenSummaryFragments = pattern;
}
/**
* Sets value of period symbol at the end of first javadoc sentence.
* @param period period's value.
*/
public void setPeriod(String period) {
this.period = period;
}
@Override
public int[] getDefaultJavadocTokens() {
return new int[] {
JavadocTokenTypes.JAVADOC,
};
}
@Override
public int[] getRequiredJavadocTokens() {
return getAcceptableJavadocTokens();
}
@Override
public void visitJavadocToken(DetailNode ast) {
if (!startsWithInheritDoc(ast)) {
final String summaryDoc = getSummarySentence(ast);
if (summaryDoc.isEmpty()) {
log(ast.getLineNumber(), MSG_SUMMARY_JAVADOC_MISSING);
}
else if (!period.isEmpty()) {
final String firstSentence = getFirstSentence(ast);
final int endOfSentence = firstSentence.lastIndexOf(period);
if (!summaryDoc.contains(period)) {
log(ast.getLineNumber(), MSG_SUMMARY_FIRST_SENTENCE);
}
if (endOfSentence != -1
&& containsForbiddenFragment(firstSentence.substring(0, endOfSentence))) {
log(ast.getLineNumber(), MSG_SUMMARY_JAVADOC);
}
}
}
}
/**
* Checks if the node starts with an {@inheritDoc}.
* @param root The root node to examine.
* @return {@code true} if the javadoc starts with an {@inheritDoc}.
*/
private static boolean startsWithInheritDoc(DetailNode root) {
boolean found = false;
final DetailNode[] children = root.getChildren();
for (int i = 0; !found && i < children.length - 1; i++) {
final DetailNode child = children[i];
if (child.getType() == JavadocTokenTypes.JAVADOC_INLINE_TAG
&& child.getChildren()[1].getType() == JavadocTokenTypes.INHERIT_DOC_LITERAL) {
found = true;
}
else if (child.getType() != JavadocTokenTypes.LEADING_ASTERISK
&& !CommonUtils.isBlank(child.getText())) {
break;
}
}
return found;
}
/**
* Checks if period is at the end of sentence.
* @param ast Javadoc root node.
* @return error string
*/
private static String getSummarySentence(DetailNode ast) {
boolean flag = true;
final StringBuilder result = new StringBuilder(256);
for (DetailNode child : ast.getChildren()) {
if (ALLOWED_TYPES.contains(child.getType())) {
result.append(child.getText());
}
else if (child.getType() == JavadocTokenTypes.HTML_ELEMENT
&& CommonUtils.isBlank(result.toString().trim())) {
result.append(getStringInsideTag(result.toString(),
child.getChildren()[0].getChildren()[0]));
}
else if (child.getType() == JavadocTokenTypes.JAVADOC_TAG) {
flag = false;
}
if (!flag) {
break;
}
}
return result.toString().trim();
}
/**
* Concatenates string within text of html tags.
* @param result javadoc string
* @param detailNode javadoc tag node
* @return java doc tag content appended in result
*/
private static String getStringInsideTag(String result, DetailNode detailNode) {
final StringBuilder contents = new StringBuilder(result);
DetailNode tempNode = detailNode;
while (tempNode != null) {
if (tempNode.getType() == JavadocTokenTypes.TEXT) {
contents.append(tempNode.getText());
}
tempNode = JavadocUtils.getNextSibling(tempNode);
}
return contents.toString();
}
/**
* Finds and returns first sentence.
* @param ast Javadoc root node.
* @return first sentence.
*/
private static String getFirstSentence(DetailNode ast) {
final StringBuilder result = new StringBuilder(256);
final String periodSuffix = PERIOD + ' ';
for (DetailNode child : ast.getChildren()) {
final String text;
if (child.getChildren().length == 0) {
text = child.getText();
}
else {
text = getFirstSentence(child);
}
if (child.getType() != JavadocTokenTypes.JAVADOC_INLINE_TAG
&& text.contains(periodSuffix)) {
result.append(text.substring(0, text.indexOf(periodSuffix) + 1));
break;
}
else {
result.append(text);
}
}
return result.toString();
}
/**
* Tests if first sentence contains forbidden summary fragment.
* @param firstSentence String with first sentence.
* @return true, if first sentence contains forbidden summary fragment.
*/
private boolean containsForbiddenFragment(String firstSentence) {
String javadocText = JAVADOC_MULTILINE_TO_SINGLELINE_PATTERN
.matcher(firstSentence).replaceAll(" ");
javadocText = CharMatcher.whitespace().trimAndCollapseFrom(javadocText, ' ');
return forbiddenSummaryFragments.matcher(javadocText).find();
}
}