diff --git a/commons/src/main/java/org/archive/util/ArchiveUtils.java b/commons/src/main/java/org/archive/util/ArchiveUtils.java
index eb7f1c4e..6e8e8d7f 100644
--- a/commons/src/main/java/org/archive/util/ArchiveUtils.java
+++ b/commons/src/main/java/org/archive/util/ArchiveUtils.java
@@ -897,14 +897,36 @@ public class ArchiveUtils {
         return TLDS.contains(dom.toUpperCase());
     }
     
-    public static void closeQuietly(Closeable input) {
+    public static void closeQuietly(Object input) {
+        if(input == null || ! (input instanceof Closeable)) {
+            return;
+        }
         try {
-            if (input != null) {
-                input.close();
-            }
+            ((Closeable)input).close();
         } catch (IOException ioe) {
             // ignore
         }
     }
+    
+    /**
+     * Perform checks as to whether normal execution should proceed.
+     * 
+     * If an external interrupt is detected, throw an interrupted exception.
+     * Used before anything that should not be attempted by a 'zombie' thread
+     * that the Frontier/Crawl has given up on.
+     * 
+     * @throws InterruptedException
+     */
+    public static void continueCheck() throws InterruptedException {
+        if(Thread.interrupted()) {
+            throw new InterruptedException("interrupt detected");
+        }
+    }
+    
+//    public static long doubleMurmur(byte[] data) {
+//        int first = MurmurHash.hash(data, 7);
+//        int second = MurmurHash.hash(data, 13);
+//        return (((long)first)<<32) | ((long)second & 0x00000000ffffffffl);
+//    }
 }
 
diff --git a/engine/src/main/java/org/archive/crawler/deciderules/ClassKeyMatchesRegExpDecideRule.java b/engine/src/main/java/org/archive/crawler/deciderules/ClassKeyMatchesRegExpDecideRule.java
index 2d731071..cf33e314 100644
--- a/engine/src/main/java/org/archive/crawler/deciderules/ClassKeyMatchesRegExpDecideRule.java
+++ b/engine/src/main/java/org/archive/crawler/deciderules/ClassKeyMatchesRegExpDecideRule.java
@@ -27,8 +27,8 @@ package org.archive.crawler.deciderules;
 
 import org.archive.crawler.framework.CrawlController;
 import org.archive.modules.CrawlURI;
-import org.archive.modules.ProcessorURI;
 import org.archive.modules.deciderules.MatchesRegExpDecideRule;
+import org.springframework.beans.factory.annotation.Autowired;
 
 
 /**
@@ -41,19 +41,24 @@ public class ClassKeyMatchesRegExpDecideRule extends MatchesRegExpDecideRule {
 
     private static final long serialVersionUID = 3L;
 
-
-    final private CrawlController controller;
+    protected CrawlController controller;
+    public CrawlController getCrawlController() {
+        return this.controller;
+    }
+    @Autowired
+    public void setCrawlController(CrawlController controller) {
+        this.controller = controller;
+    }
     
     /**
      * Usual constructor. 
      */
-    public ClassKeyMatchesRegExpDecideRule(CrawlController controller) {
-        this.controller = controller;
+    public ClassKeyMatchesRegExpDecideRule() {
     }
 
     
     @Override
-    protected String getString(ProcessorURI uri) {
+    protected String getString(CrawlURI uri) {
         CrawlURI curi = (CrawlURI)uri;
         return controller.getFrontier().getClassKey(curi);
     }