001//////////////////////////////////////////////////////////////////////////////// 002// checkstyle: Checks Java source code for adherence to a set of rules. 003// Copyright (C) 2001-2017 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.filters; 021 022import java.lang.ref.WeakReference; 023import java.util.ArrayList; 024import java.util.Collection; 025import java.util.Collections; 026import java.util.List; 027import java.util.Objects; 028import java.util.regex.Matcher; 029import java.util.regex.Pattern; 030import java.util.regex.PatternSyntaxException; 031 032import org.apache.commons.beanutils.ConversionException; 033 034import com.puppycrawl.tools.checkstyle.api.AuditEvent; 035import com.puppycrawl.tools.checkstyle.api.AutomaticBean; 036import com.puppycrawl.tools.checkstyle.api.FileContents; 037import com.puppycrawl.tools.checkstyle.api.Filter; 038import com.puppycrawl.tools.checkstyle.api.TextBlock; 039import com.puppycrawl.tools.checkstyle.checks.FileContentsHolder; 040import com.puppycrawl.tools.checkstyle.utils.CommonUtils; 041 042/** 043 * <p> 044 * A filter that uses nearby comments to suppress audit events. 045 * </p> 046 * 047 * <p>This check is philosophically similar to {@link SuppressionCommentFilter}. 048 * Unlike {@link SuppressionCommentFilter}, this filter does not require 049 * pairs of comments. This check may be used to suppress warnings in the 050 * current line: 051 * <pre> 052 * offendingLine(for, whatever, reason); // SUPPRESS ParameterNumberCheck 053 * </pre> 054 * or it may be configured to span multiple lines, either forward: 055 * <pre> 056 * // PERMIT MultipleVariableDeclarations NEXT 3 LINES 057 * double x1 = 1.0, y1 = 0.0, z1 = 0.0; 058 * double x2 = 0.0, y2 = 1.0, z2 = 0.0; 059 * double x3 = 0.0, y3 = 0.0, z3 = 1.0; 060 * </pre> 061 * or reverse: 062 * <pre> 063 * try { 064 * thirdPartyLibrary.method(); 065 * } catch (RuntimeException ex) { 066 * // ALLOW ILLEGAL CATCH BECAUSE third party API wraps everything 067 * // in RuntimeExceptions. 068 * ... 069 * } 070 * </pre> 071 * 072 * <p>See {@link SuppressionCommentFilter} for usage notes. 073 * 074 * @author Mick Killianey 075 */ 076public class SuppressWithNearbyCommentFilter 077 extends AutomaticBean 078 implements Filter { 079 080 /** Format to turns checkstyle reporting off. */ 081 private static final String DEFAULT_COMMENT_FORMAT = 082 "SUPPRESS CHECKSTYLE (\\w+)"; 083 084 /** Default regex for checks that should be suppressed. */ 085 private static final String DEFAULT_CHECK_FORMAT = ".*"; 086 087 /** Default regex for lines that should be suppressed. */ 088 private static final String DEFAULT_INFLUENCE_FORMAT = "0"; 089 090 /** Tagged comments. */ 091 private final List<Tag> tags = new ArrayList<>(); 092 093 /** Whether to look for trigger in C-style comments. */ 094 private boolean checkC = true; 095 096 /** Whether to look for trigger in C++-style comments. */ 097 // -@cs[AbbreviationAsWordInName] We can not change it as, 098 // check's property is a part of API (used in configurations). 099 private boolean checkCPP = true; 100 101 /** Parsed comment regexp that marks checkstyle suppression region. */ 102 private Pattern commentFormat = Pattern.compile(DEFAULT_COMMENT_FORMAT); 103 104 /** The comment pattern that triggers suppression. */ 105 private String checkFormat = DEFAULT_CHECK_FORMAT; 106 107 /** The message format to suppress. */ 108 private String messageFormat; 109 110 /** The influence of the suppression comment. */ 111 private String influenceFormat = DEFAULT_INFLUENCE_FORMAT; 112 113 /** 114 * References the current FileContents for this filter. 115 * Since this is a weak reference to the FileContents, the FileContents 116 * can be reclaimed as soon as the strong references in TreeWalker 117 * and FileContentsHolder are reassigned to the next FileContents, 118 * at which time filtering for the current FileContents is finished. 119 */ 120 private WeakReference<FileContents> fileContentsReference = new WeakReference<>(null); 121 122 /** 123 * Set the format for a comment that turns off reporting. 124 * @param pattern a pattern. 125 */ 126 public final void setCommentFormat(Pattern pattern) { 127 commentFormat = pattern; 128 } 129 130 /** 131 * @return the FileContents for this filter. 132 */ 133 public FileContents getFileContents() { 134 return fileContentsReference.get(); 135 } 136 137 /** 138 * Set the FileContents for this filter. 139 * @param fileContents the FileContents for this filter. 140 */ 141 public void setFileContents(FileContents fileContents) { 142 fileContentsReference = new WeakReference<>(fileContents); 143 } 144 145 /** 146 * Set the format for a check. 147 * @param format a {@code String} value 148 */ 149 public final void setCheckFormat(String format) { 150 checkFormat = format; 151 } 152 153 /** 154 * Set the format for a message. 155 * @param format a {@code String} value 156 */ 157 public void setMessageFormat(String format) { 158 messageFormat = format; 159 } 160 161 /** 162 * Set the format for the influence of this check. 163 * @param format a {@code String} value 164 */ 165 public final void setInfluenceFormat(String format) { 166 influenceFormat = format; 167 } 168 169 /** 170 * Set whether to look in C++ comments. 171 * @param checkCpp {@code true} if C++ comments are checked. 172 */ 173 // -@cs[AbbreviationAsWordInName] We can not change it as, 174 // check's property is a part of API (used in configurations). 175 public void setCheckCPP(boolean checkCpp) { 176 checkCPP = checkCpp; 177 } 178 179 /** 180 * Set whether to look in C comments. 181 * @param checkC {@code true} if C comments are checked. 182 */ 183 public void setCheckC(boolean checkC) { 184 this.checkC = checkC; 185 } 186 187 @Override 188 public boolean accept(AuditEvent event) { 189 boolean accepted = true; 190 191 if (event.getLocalizedMessage() != null) { 192 // Lazy update. If the first event for the current file, update file 193 // contents and tag suppressions 194 final FileContents currentContents = FileContentsHolder.getCurrentFileContents(); 195 196 if (getFileContents() != currentContents) { 197 setFileContents(currentContents); 198 tagSuppressions(); 199 } 200 if (matchesTag(event)) { 201 accepted = false; 202 } 203 } 204 return accepted; 205 } 206 207 /** 208 * Whether current event matches any tag from {@link #tags}. 209 * @param event AuditEvent to test match on {@link #tags}. 210 * @return true if event matches any tag from {@link #tags}, false otherwise. 211 */ 212 private boolean matchesTag(AuditEvent event) { 213 for (final Tag tag : tags) { 214 if (tag.isMatch(event)) { 215 return true; 216 } 217 } 218 return false; 219 } 220 221 /** 222 * Collects all the suppression tags for all comments into a list and 223 * sorts the list. 224 */ 225 private void tagSuppressions() { 226 tags.clear(); 227 final FileContents contents = getFileContents(); 228 if (checkCPP) { 229 tagSuppressions(contents.getCppComments().values()); 230 } 231 if (checkC) { 232 final Collection<List<TextBlock>> cComments = 233 contents.getCComments().values(); 234 cComments.forEach(this::tagSuppressions); 235 } 236 Collections.sort(tags); 237 } 238 239 /** 240 * Appends the suppressions in a collection of comments to the full 241 * set of suppression tags. 242 * @param comments the set of comments. 243 */ 244 private void tagSuppressions(Collection<TextBlock> comments) { 245 for (final TextBlock comment : comments) { 246 final int startLineNo = comment.getStartLineNo(); 247 final String[] text = comment.getText(); 248 tagCommentLine(text[0], startLineNo); 249 for (int i = 1; i < text.length; i++) { 250 tagCommentLine(text[i], startLineNo + i); 251 } 252 } 253 } 254 255 /** 256 * Tags a string if it matches the format for turning 257 * checkstyle reporting on or the format for turning reporting off. 258 * @param text the string to tag. 259 * @param line the line number of text. 260 */ 261 private void tagCommentLine(String text, int line) { 262 final Matcher matcher = commentFormat.matcher(text); 263 if (matcher.find()) { 264 addTag(matcher.group(0), line); 265 } 266 } 267 268 /** 269 * Adds a comment suppression {@code Tag} to the list of all tags. 270 * @param text the text of the tag. 271 * @param line the line number of the tag. 272 */ 273 private void addTag(String text, int line) { 274 final Tag tag = new Tag(text, line, this); 275 tags.add(tag); 276 } 277 278 /** 279 * A Tag holds a suppression comment and its location. 280 */ 281 public static class Tag implements Comparable<Tag> { 282 /** The text of the tag. */ 283 private final String text; 284 285 /** The first line where warnings may be suppressed. */ 286 private final int firstLine; 287 288 /** The last line where warnings may be suppressed. */ 289 private final int lastLine; 290 291 /** The parsed check regexp, expanded for the text of this tag. */ 292 private final Pattern tagCheckRegexp; 293 294 /** The parsed message regexp, expanded for the text of this tag. */ 295 private final Pattern tagMessageRegexp; 296 297 /** 298 * Constructs a tag. 299 * @param text the text of the suppression. 300 * @param line the line number. 301 * @param filter the {@code SuppressWithNearbyCommentFilter} with the context 302 * @throws ConversionException if unable to parse expanded text. 303 */ 304 public Tag(String text, int line, SuppressWithNearbyCommentFilter filter) { 305 this.text = text; 306 307 //Expand regexp for check and message 308 //Does not intern Patterns with Utils.getPattern() 309 String format = ""; 310 try { 311 format = CommonUtils.fillTemplateWithStringsByRegexp( 312 filter.checkFormat, text, filter.commentFormat); 313 tagCheckRegexp = Pattern.compile(format); 314 if (filter.messageFormat == null) { 315 tagMessageRegexp = null; 316 } 317 else { 318 format = CommonUtils.fillTemplateWithStringsByRegexp( 319 filter.messageFormat, text, filter.commentFormat); 320 tagMessageRegexp = Pattern.compile(format); 321 } 322 format = CommonUtils.fillTemplateWithStringsByRegexp( 323 filter.influenceFormat, text, filter.commentFormat); 324 final int influence; 325 try { 326 if (CommonUtils.startsWithChar(format, '+')) { 327 format = format.substring(1); 328 } 329 influence = Integer.parseInt(format); 330 } 331 catch (final NumberFormatException ex) { 332 throw new ConversionException( 333 "unable to parse influence from '" + text 334 + "' using " + filter.influenceFormat, ex); 335 } 336 if (influence >= 0) { 337 firstLine = line; 338 lastLine = line + influence; 339 } 340 else { 341 firstLine = line + influence; 342 lastLine = line; 343 } 344 } 345 catch (final PatternSyntaxException ex) { 346 throw new ConversionException( 347 "unable to parse expanded comment " + format, 348 ex); 349 } 350 } 351 352 /** 353 * Compares the position of this tag in the file 354 * with the position of another tag. 355 * @param other the tag to compare with this one. 356 * @return a negative number if this tag is before the other tag, 357 * 0 if they are at the same position, and a positive number if this 358 * tag is after the other tag. 359 */ 360 @Override 361 public int compareTo(Tag other) { 362 if (firstLine == other.firstLine) { 363 return Integer.compare(lastLine, other.lastLine); 364 } 365 366 return Integer.compare(firstLine, other.firstLine); 367 } 368 369 @Override 370 public boolean equals(Object other) { 371 if (this == other) { 372 return true; 373 } 374 if (other == null || getClass() != other.getClass()) { 375 return false; 376 } 377 final Tag tag = (Tag) other; 378 return Objects.equals(firstLine, tag.firstLine) 379 && Objects.equals(lastLine, tag.lastLine) 380 && Objects.equals(text, tag.text) 381 && Objects.equals(tagCheckRegexp, tag.tagCheckRegexp) 382 && Objects.equals(tagMessageRegexp, tag.tagMessageRegexp); 383 } 384 385 @Override 386 public int hashCode() { 387 return Objects.hash(text, firstLine, lastLine, tagCheckRegexp, tagMessageRegexp); 388 } 389 390 /** 391 * Determines whether the source of an audit event 392 * matches the text of this tag. 393 * @param event the {@code AuditEvent} to check. 394 * @return true if the source of event matches the text of this tag. 395 */ 396 public boolean isMatch(AuditEvent event) { 397 final int line = event.getLine(); 398 boolean match = false; 399 400 if (line >= firstLine && line <= lastLine) { 401 final Matcher tagMatcher = tagCheckRegexp.matcher(event.getSourceName()); 402 403 if (tagMatcher.find()) { 404 match = true; 405 } 406 else if (tagMessageRegexp == null) { 407 if (event.getModuleId() != null) { 408 final Matcher idMatcher = tagCheckRegexp.matcher(event.getModuleId()); 409 match = idMatcher.find(); 410 } 411 } 412 else { 413 final Matcher messageMatcher = tagMessageRegexp.matcher(event.getMessage()); 414 match = messageMatcher.find(); 415 } 416 } 417 return match; 418 } 419 420 @Override 421 public final String toString() { 422 return "Tag[lines=[" + firstLine + " to " + lastLine 423 + "]; text='" + text + "']"; 424 } 425 } 426}