Issue #4714: Make SuppressionCommentFilter and SuppressWithNearbyCommentFilter children of TreeWalker

config/checkstyle_checks.xml

@@ -31,24 +31,10 @@
     <property name="severity" value="ignore"/>
     <property name="acceptOnMatch" value="false"/>
   </module>
-  <module name="SuppressionCommentFilter">
-    <!--
-      Use suppressions.xml for suppressions, this is only example.
-      checkFormat will prevent suppression comments from being valid.
-    -->
-    <property name="checkFormat" value="IGNORETHIS"/>
-    <property name="offCommentFormat" value="CSOFF\: .*"/>
-    <property name="onCommentFormat" value="CSON\: .*"/>
-  </module>
   <module name="SuppressionFilter">
     <property name="file" value="${checkstyle.suppressions.file}"/>
   </module>
   <module name="SuppressWarningsFilter"/>
-  <module name="SuppressWithNearbyCommentFilter">
-    <property name="commentFormat" value="-@cs\[(\w{8,}(\|\w{8,})*)\] \w[\(\)\-\.\'\`\,\:\;\w ]{10,}"/>
-    <property name="checkFormat" value="$1"/>
-    <property name="influenceFormat" value="3"/>
-  </module>
 
   <!-- Headers -->
   <module name="Header">
@@ -298,6 +284,22 @@
     <module name="UnnecessaryParentheses"/>
     <module name="VariableDeclarationUsageDistance"/>
 
+    <!-- Filters-->
+    <module name="SuppressionCommentFilter">
+      <!--
+        Use suppressions.xml for suppressions, this is only example.
+        checkFormat will prevent suppression comments from being valid.
+      -->
+      <property name="checkFormat" value="IGNORETHIS"/>
+      <property name="offCommentFormat" value="CSOFF\: .*"/>
+      <property name="onCommentFormat" value="CSON\: .*"/>
+    </module>
+    <module name="SuppressWithNearbyCommentFilter">
+      <property name="commentFormat" value="-@cs\[(\w{8,}(\|\w{8,})*)\] \w[\(\)\-\.\'\`\,\:\;\w ]{10,}"/>
+      <property name="checkFormat" value="$1"/>
+      <property name="influenceFormat" value="3"/>
+    </module>
+
     <!-- Imports -->
     <module name="AvoidStarImport"/>
     <module name="AvoidStaticImport"/>

config/checkstyle_sevntu_checks.xml

@@ -14,13 +14,13 @@
     <module name="SuppressionFilter">
         <property name="file" value="${project.basedir}/config/sevntu_suppressions.xml"/>
     </module>
-    <module name="SuppressWithNearbyCommentFilter">
-        <property name="commentFormat" value="-@cs\[(\w{8,})\] \w[\(\)\-\.\'\`\,\:\;\w ]{10,}"/>
-        <property name="checkFormat" value="$1"/>
-        <property name="influenceFormat" value="3"/>
-    </module>
 
     <module name="TreeWalker">
+        <module name="SuppressWithNearbyCommentFilter">
+            <property name="commentFormat" value="-@cs\[(\w{8,})\] \w[\(\)\-\.\'\`\,\:\;\w ]{10,}"/>
+            <property name="checkFormat" value="$1"/>
+            <property name="influenceFormat" value="3"/>
+        </module>
         <module name="FileContentsHolder"/>
         <module name="StaticMethodCandidate"/>
         <module name="UselessSingleCatchCheck"/>

config/import-control.xml

@@ -142,6 +142,8 @@
 
   <subpackage name="filters">
     <allow class="java.lang.ref.WeakReference" local-only="true"/>
+    <allow class="com.puppycrawl.tools.checkstyle.TreeWalkerAuditEvent" local-only="true"/>
+    <allow class="com.puppycrawl.tools.checkstyle.TreeWalkerFilter" local-only="true"/>
     <disallow pkg="com\.puppycrawl\.tools\.checkstyle\.checks\.[^.]+" regex="true"/>
     <allow pkg="com.puppycrawl.tools.checkstyle.utils"/>
   </subpackage>

pom.xml

@@ -517,6 +517,9 @@
             <id>sevntu-checkstyle-check</id>
             <phase>verify</phase>
             <configuration>
+              <!-- skipped until sevntu-checks to 8.1 upgrade
+              see https://github.com/checkstyle/checkstyle/pull/4755 -->
+              <skip>true</skip>
               <configLocation>${project.basedir}/config/checkstyle_sevntu_checks.xml</configLocation>
               <failOnViolation>true</failOnViolation>
               <includeResources>false</includeResources>

src/main/java/com/puppycrawl/tools/checkstyle/TreeWalker.java

@@ -29,6 +29,8 @@
 import java.util.Locale;
 import java.util.Map.Entry;
 import java.util.Set;
+import java.util.SortedSet;
+import java.util.TreeSet;
 
 import antlr.CommonHiddenStreamToken;
 import antlr.RecognitionException;
@@ -40,13 +42,15 @@
 import com.google.common.collect.Multimap;
 import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
 import com.puppycrawl.tools.checkstyle.api.AbstractFileSetCheck;
+import com.puppycrawl.tools.checkstyle.api.AutomaticBean;
 import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
 import com.puppycrawl.tools.checkstyle.api.Configuration;
 import com.puppycrawl.tools.checkstyle.api.Context;
 import com.puppycrawl.tools.checkstyle.api.DetailAST;
 import com.puppycrawl.tools.checkstyle.api.ExternalResourceHolder;
 import com.puppycrawl.tools.checkstyle.api.FileContents;
 import com.puppycrawl.tools.checkstyle.api.FileText;
+import com.puppycrawl.tools.checkstyle.api.LocalizedMessage;
 import com.puppycrawl.tools.checkstyle.api.TokenTypes;
 import com.puppycrawl.tools.checkstyle.grammars.GeneratedJavaLexer;
 import com.puppycrawl.tools.checkstyle.grammars.GeneratedJavaRecognizer;
@@ -59,6 +63,9 @@
  *
  * @author Oliver Burn
  */
+// -@cs[ClassFanOutComplexity] To resolve issue 4714, new classes were imported. Number of
+// classes current class relies on currently is 27, which is above threshold 25.
+// see https://github.com/checkstyle/checkstyle/issues/4714.
 public final class TreeWalker extends AbstractFileSetCheck implements ExternalResourceHolder {
 
     /** Default distance between tab stops. */
@@ -78,6 +85,12 @@ public final class TreeWalker extends AbstractFileSetCheck implements ExternalRe
     /** Registered comment checks. */
     private final Set<AbstractCheck> commentChecks = new HashSet<>();
 
+    /** The ast filters. */
+    private final Set<TreeWalkerFilter> filters = new HashSet<>();
+
+    /** The sorted set of messages. */
+    private final SortedSet<LocalizedMessage> messages = new TreeSet<>();
+
     /** The distance between tab stops. */
     private int tabWidth = DEFAULT_TAB_WIDTH;
 
@@ -144,23 +157,35 @@ public void finishLocalSetup() {
         childContext = checkContext;
     }
 
+    /**
+     * {@inheritDoc} Creates child module.
+     * @noinspection ChainOfInstanceofChecks
+     */
     @Override
     public void setupChild(Configuration childConf)
             throws CheckstyleException {
         final String name = childConf.getName();
         final Object module = moduleFactory.createModule(name);
-        if (!(module instanceof AbstractCheck)) {
+        if (module instanceof AutomaticBean) {
+            final AutomaticBean bean = (AutomaticBean) module;
+            bean.contextualize(childContext);
+            bean.configure(childConf);
+        }
+        if (module instanceof AbstractCheck) {
+            final AbstractCheck check = (AbstractCheck) module;
+            check.init();
+            registerCheck(check);
+        }
+        else if (module instanceof TreeWalkerFilter) {
+            final TreeWalkerFilter filter = (TreeWalkerFilter) module;
+            filters.add(filter);
+        }
+        else {
             throw new CheckstyleException(
                 "TreeWalker is not allowed as a parent of " + name
                         + " Please review 'Parent Module' section for this Check in web"
                         + " documentation if Check is standard.");
         }
-        final AbstractCheck check = (AbstractCheck) module;
-        check.contextualize(childContext);
-        check.configure(childConf);
-        check.init();
-
-        registerCheck(check);
     }
 
     @Override
@@ -169,6 +194,7 @@ protected void processFiltered(File file, FileText fileText) throws CheckstyleEx
         if (CommonUtils.matchesFileExtension(file, getFileExtensions())) {
             final String msg = "%s occurred during the analysis of file %s.";
             final String fileName = file.getPath();
+
             try {
                 if (!ordinaryChecks.isEmpty()
                         || !commentChecks.isEmpty()) {
@@ -183,6 +209,10 @@ protected void processFiltered(File file, FileText fileText) throws CheckstyleEx
 
                         walk(astWithComments, contents, AstState.WITH_COMMENTS);
                     }
+                    final SortedSet<LocalizedMessage> filteredMessages =
+                            getFilteredMessages(fileName, contents);
+                    addMessages(filteredMessages);
+                    messages.clear();
                 }
             }
             catch (final TokenStreamRecognitionException tre) {
@@ -198,6 +228,28 @@ protected void processFiltered(File file, FileText fileText) throws CheckstyleEx
         }
     }
 
+    /**
+     * Returns filtered set of {@link LocalizedMessage}.
+     * @param fileName path to the file
+     * @param fileContents the contents of the file
+     * @return filtered set of messages
+     */
+    private SortedSet<LocalizedMessage> getFilteredMessages(String fileName,
+                                                            FileContents fileContents) {
+        final SortedSet<LocalizedMessage> result = new TreeSet<>(messages);
+        for (LocalizedMessage element : messages) {
+            final TreeWalkerAuditEvent event =
+                    new TreeWalkerAuditEvent(fileContents, fileName, element);
+            for (TreeWalkerFilter filter : filters) {
+                if (!filter.accept(event)) {
+                    result.remove(element);
+                    break;
+                }
+            }
+        }
+        return result;
+    }
+
     /**
      * Register a check for a given configuration.
      * @param check the check to register
@@ -350,7 +402,7 @@ private void notifyEnd(DetailAST rootAST, AstState astState) {
 
         for (AbstractCheck check : checks) {
             check.finishTree(rootAST);
-            addMessages(check.getMessages());
+            messages.addAll(check.getMessages());
         }
     }
 

src/main/java/com/puppycrawl/tools/checkstyle/TreeWalkerAuditEvent.java

@@ -0,0 +1,118 @@
+////////////////////////////////////////////////////////////////////////////////
+// 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;
+
+import com.puppycrawl.tools.checkstyle.api.FileContents;
+import com.puppycrawl.tools.checkstyle.api.LocalizedMessage;
+
+/**
+ * Raw {@code TreeWalker} event for audit.
+ *
+ * @author Timur Tibeyev
+ */
+public class TreeWalkerAuditEvent {
+    /** Filename event associated with. **/
+    private final String fileName;
+    /** The file contents. */
+    private final FileContents fileContents;
+    /** Message associated with the event. **/
+    private final LocalizedMessage localizedMessage;
+
+    /**
+     * Creates a new {@code TreeWalkerAuditEvent} instance.
+     *
+     * @param fileContents contents of the file associated with the event
+     * @param fileName file associated with the event
+     * @param localizedMessage the actual message
+     */
+    public TreeWalkerAuditEvent(FileContents fileContents, String fileName,
+                                LocalizedMessage localizedMessage) {
+        this.fileContents = fileContents;
+        this.fileName = fileName;
+        this.localizedMessage = localizedMessage;
+    }
+
+    /**
+     * Returns name of file being audited.
+     * @return the file name currently being audited or null if there is
+     *     no relation to a file.
+     */
+    public String getFileName() {
+        return fileName;
+    }
+
+    /**
+     * Returns contents of the file.
+     * @return contents of the file.
+     */
+    public FileContents getFileContents() {
+        return fileContents;
+    }
+
+    /**
+     * Gets the localized message.
+     * @return the localized message
+     */
+    public LocalizedMessage getLocalizedMessage() {
+        return localizedMessage;
+    }
+
+    /**
+     * Return the line number on the source file where the event occurred.
+     * This may be 0 if there is no relation to a file content.
+     * @return an integer representing the line number in the file source code.
+     */
+    public int getLine() {
+        return localizedMessage.getLineNo();
+    }
+
+    /**
+     * Return the message associated to the event.
+     * @return the event message
+     */
+    public String getMessage() {
+        return localizedMessage.getMessage();
+    }
+
+    /**
+     * Gets the column associated with the message.
+     * @return the column associated with the message
+     */
+    public int getColumn() {
+        return localizedMessage.getColumnNo();
+    }
+
+    /**
+     * Returns id of module.
+     * @return the identifier of the module that generated the event. Can return
+     *         null.
+     */
+    public String getModuleId() {
+        return localizedMessage.getModuleId();
+    }
+
+    /**
+     * Gets the name of the source for the message.
+     * @return the name of the source for the message
+     */
+    public String getSourceName() {
+        return localizedMessage.getSourceName();
+    }
+}

src/main/java/com/puppycrawl/tools/checkstyle/TreeWalkerFilter.java

@@ -0,0 +1,35 @@
+////////////////////////////////////////////////////////////////////////////////
+// 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;
+
+/**
+ * An interface for filtering {@code TreeWalkerAuditEvent}.
+ *
+ * @author Timur Tibeyev.
+ */
+@FunctionalInterface
+public interface TreeWalkerFilter {
+    /**
+     * Determines whether or not a filtered {@code TreeWalkerAuditEvent} is accepted.
+     * @param treeWalkerAuditEvent the TreeWalkerAuditEvent to filter.
+     * @return true if the event is accepted.
+     */
+    boolean accept(TreeWalkerAuditEvent treeWalkerAuditEvent);
+}