////////////////////////////////////////////////////////////////////////////////
// checkstyle: Checks Java source code for adherence to a set of rules.
// Copyright (C) 2001-2017 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.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.api.TokenTypes;
import com.puppycrawl.tools.checkstyle.utils.CommonUtils;
/**
* <p>
* Checks that <a href=
* "http://www.oracle.com/technetwork/java/javase/documentation/index-137868.html#firstsentence">
* Javadoc summary sentence</a> does not contain phrases that are not recommended to use.
* By default Check validate that first sentence is not empty:</p><br>
* <pre>
* <module name="SummaryJavadocCheck"/>
* </pre>
*
* <p>To ensure that summary do not contain phrase like "This method returns",
* use following config:
*
* <pre>
* <module name="SummaryJavadocCheck">
* <property name="forbiddenSummaryFragments"
* value="^This method returns.*"/>
* </module>
* </pre>
* <p>
* To specify period symbol at the end of first javadoc sentence - use following config:
* </p>
* <pre>
* <module name="SummaryJavadocCheck">
* <property name="period"
* value="period"/>
* </module>
* </pre>
*
*
* @author max
* @author <a href="mailto:nesterenko-aleksey@list.ru">Aleksey Nesterenko</a>
*/
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";
/**
* 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 = ".";
/**
* Stores allowed values in document for inherit doc literal.
*/
private static final Set<Integer> SKIP_TOKENS = new HashSet<>(
Arrays.asList(JavadocTokenTypes.NEWLINE,
JavadocTokenTypes.LEADING_ASTERISK,
JavadocTokenTypes.EOF)
);
/**
* 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 int[] getAcceptableTokens() {
return new int[] {TokenTypes.BLOCK_COMMENT_BEGIN };
}
@Override
public int[] getRequiredTokens() {
return getAcceptableTokens();
}
@Override
public void visitJavadocToken(DetailNode ast) {
String firstSentence = getFirstSentence(ast);
final int endOfSentence = firstSentence.lastIndexOf(period);
if (endOfSentence == -1) {
if (!isOnlyInheritDoc(ast)) {
log(ast.getLineNumber(), MSG_SUMMARY_FIRST_SENTENCE);
}
}
else {
firstSentence = firstSentence.substring(0, endOfSentence);
if (containsForbiddenFragment(firstSentence)) {
log(ast.getLineNumber(), MSG_SUMMARY_JAVADOC);
}
}
}
/**
* Finds if inheritDoc is placed properly in java doc.
* @param ast Javadoc root node.
* @return true if inheritDoc is valid or false.
*/
private static boolean isOnlyInheritDoc(DetailNode ast) {
boolean extraTextFound = false;
boolean containsInheritDoc = false;
for (DetailNode child : ast.getChildren()) {
if (child.getType() == JavadocTokenTypes.TEXT) {
if (!CommonUtils.isBlank(child.getText())) {
extraTextFound = true;
}
}
else if (child.getType() == JavadocTokenTypes.JAVADOC_INLINE_TAG) {
if (child.getChildren()[1].getType() == JavadocTokenTypes.INHERIT_DOC_LITERAL) {
containsInheritDoc = true;
}
else {
extraTextFound = true;
}
}
else if (!SKIP_TOKENS.contains(child.getType())) {
extraTextFound = true;
}
if (extraTextFound) {
break;
}
}
return containsInheritDoc && !extraTextFound;
}
/**
* Finds and returns first sentence.
* @param ast Javadoc root node.
* @return first sentence.
*/
private static String getFirstSentence(DetailNode ast) {
final StringBuilder result = new StringBuilder();
final String periodSuffix = PERIOD + ' ';
for (DetailNode child : ast.getChildren()) {
final String text = child.getText();
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();
}
}