Pull checkstyle#242: Metadata Integration

.gitignore

@@ -2,3 +2,7 @@
 */target/
 metadata-gen/
 net.sf.eclipsecs.core/lib/metadata-gen-1.0-SNAPSHOT.jar
+.idea/
+*.iml
+*.prefs
+.checkstyle

net.sf.eclipsecs.checkstyle/pom.xml

@@ -87,4 +87,4 @@
             </plugin>
         </plugins>
     </build>
-</project>
+</project>

net.sf.eclipsecs.core/.classpath

@@ -4,5 +4,8 @@
 	<classpathentry kind="con" path="org.eclipse.pde.core.requiredPlugins"/>
 	<classpathentry kind="src" path="src"/>
 	<classpathentry exported="true" kind="lib" path="lib/dom4j-2.1.3.jar"/>
+	<classpathentry exported="true" kind="lib" path="lib/metadata-gen-1.0-SNAPSHOT.jar"/>
+	<classpathentry exported="true" kind="lib" path="lib/reflections-0.9.10.jar"/>
+	<classpathentry exported="true" kind="lib" path="lib/snakeyaml-1.26.jar"/>
 	<classpathentry kind="output" path="target/classes"/>
 </classpath>

net.sf.eclipsecs.core/META-INF/MANIFEST.MF

@@ -5,7 +5,10 @@ Bundle-SymbolicName: net.sf.eclipsecs.core;singleton:=true
 Bundle-Version: 8.34.0.qualifier
 Bundle-RequiredExecutionEnvironment: JavaSE-1.8
 Bundle-ClassPath: .,
- lib/dom4j-2.1.3.jar
+ lib/dom4j-2.1.3.jar,
+ lib/snakeyaml-1.26.jar,
+ lib/reflections-0.9.10.jar,
+ lib/metadata-gen-1.0-SNAPSHOT.jar
 Bundle-Activator: net.sf.eclipsecs.core.CheckstylePlugin
 Bundle-ActivationPolicy: lazy
 Bundle-Vendor: Eclipse Checkstyle Project

net.sf.eclipsecs.core/build.properties

@@ -7,6 +7,10 @@ bin.includes = .,\
                plugin.xml,\
                schema/,\
                core.properties,\
-               lib/dom4j-2.1.3.jar
+               lib/dom4j-2.1.3.jar, \
+               lib/reflections-0.9.10.jar, \
+               lib/snakeyaml-1.26.jar, \
+               lib/metadata-gen-1.0-SNAPSHOT.jar
+
 source.. = src/
 

net.sf.eclipsecs.core/src/net/sf/eclipsecs/core/config/meta/CheckUtil.java

@@ -0,0 +1,75 @@
+package net.sf.eclipsecs.core.config.meta;
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+import com.puppycrawl.tools.checkstyle.PackageNamesLoader;
+import com.puppycrawl.tools.checkstyle.PackageObjectFactory;
+import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
+import com.puppycrawl.tools.checkstyle.api.CheckstyleException;
+import com.puppycrawl.tools.checkstyle.checks.javadoc.AbstractJavadocCheck;
+import com.puppycrawl.tools.checkstyle.utils.JavadocUtil;
+import com.puppycrawl.tools.checkstyle.utils.TokenUtil;
+
+import net.sf.eclipsecs.core.CheckstylePlugin;
+
+public final class CheckUtil {
+    private CheckUtil() {
+    }
+
+    public static String getModifiableTokens(String checkName) {
+      final Object checkResult = getCheck(checkName);
+      String result = null;
+      if (AbstractJavadocCheck.class.isAssignableFrom(checkResult.getClass())) {
+          final AbstractJavadocCheck javadocCheck = (AbstractJavadocCheck) checkResult;
+          final List<Integer> modifiableJavadocTokens = subtractTokens(javadocCheck.getAcceptableJavadocTokens(),
+                  javadocCheck.getRequiredJavadocTokens());
+          result = getTokens(JavadocUtil::getTokenName, modifiableJavadocTokens);
+      }
+      else if (AbstractCheck.class.isAssignableFrom(checkResult.getClass())) {
+          final AbstractCheck check = (AbstractCheck) checkResult;
+          final List<Integer> modifiableTokens = subtractTokens(check.getAcceptableTokens(),
+                  check.getRequiredTokens());
+          result = getTokens(TokenUtil::getTokenName, modifiableTokens);
+      }
+      else {
+        throw new IllegalStateException("Exception caused in CheckUtil.getCheck, "
+                + "method executed in wrong context, heirarchy of check class missing");
+      }
+      return result;
+   }
+
+    private static AbstractCheck getCheck(String checkName) {
+        final ClassLoader classLoader = CheckstylePlugin.getDefault()
+                .getAddonExtensionClassLoader();
+        try {
+            final Set<String> packageNames = PackageNamesLoader.getPackageNames(classLoader);
+            return (AbstractCheck) new PackageObjectFactory(packageNames, classLoader)
+                    .createModule(checkName);
+        }
+        catch (CheckstyleException ex) {
+            throw new IllegalStateException("exception occured during load of " + checkName, ex);
+        }
+    }
+
+    private static List<Integer> subtractTokens(int[] tokens, int... requiredTokens) {
+      Set<Integer> requiredTokensSet = new HashSet<>(Arrays.stream(requiredTokens)
+              .boxed()
+              .collect(Collectors.toList()));
+      return Arrays.stream(tokens)
+              .boxed()
+              .filter(token -> !requiredTokensSet.contains(token))
+              .collect(Collectors.toList());
+    }
+
+    private static String getTokens(Function<Integer, String> function, List<Integer> modifiableTokens) {
+      return modifiableTokens.stream()
+            .map(tokenInteger -> function.apply(tokenInteger))
+            .collect(Collectors.joining(","));
+    }
+}
+