diff --git a/lucene/facet/src/java/org/apache/lucene/facet/sortedset/FacetCounter.java b/lucene/facet/src/java/org/apache/lucene/facet/sortedset/FacetCounter.java
new file mode 100644
index 0000000..d521517
--- /dev/null
+++ b/lucene/facet/src/java/org/apache/lucene/facet/sortedset/FacetCounter.java
@@ -0,0 +1,16 @@
+package org.apache.lucene.facet.sortedset;
+
+/**
+ * Facet counting abstraction
+ */
+public interface FacetCounter {
+  /**
+   * increment term with ord by count
+   */
+  void increment(int ord, int count);
+  
+  /**
+   * get accumulated count for a term ord
+   */
+  int getCount(int ord);
+}
diff --git a/lucene/facet/src/java/org/apache/lucene/facet/sortedset/SortedSetDocValuesFacetCounts.java b/lucene/facet/src/java/org/apache/lucene/facet/sortedset/SortedSetDocValuesFacetCounts.java
index a8fcfc6..5f718cb 100644
--- a/lucene/facet/src/java/org/apache/lucene/facet/sortedset/SortedSetDocValuesFacetCounts.java
+++ b/lucene/facet/src/java/org/apache/lucene/facet/sortedset/SortedSetDocValuesFacetCounts.java
@@ -62,7 +62,7 @@ public class SortedSetDocValuesFacetCounts extends Facets {
   final SortedSetDocValuesReaderState state;
   final SortedSetDocValues dv;
   final String field;
-  final int[] counts;
+  final FacetCounter counter;
 
   /** Sparse faceting: returns any dimension that had any
    *  hits, topCount labels per dimension. */
@@ -70,11 +70,31 @@ public class SortedSetDocValuesFacetCounts extends Facets {
       throws IOException {
     this.state = state;
     this.field = state.getField();
-    counts = new int[state.getSize()];
+    counter = getFacetCounter(state.getSize());
     dv = state.getDocValues();
     //System.out.println("field=" + field);
     count(hits.getMatchingDocs());
   }
+  
+  /**
+   * default impl for an array-backed {@link FacetCounter}
+   */
+  public FacetCounter getFacetCounter(final int numValues) {
+    return new FacetCounter() {
+      int[] counts = new int[numValues];
+      
+      @Override
+      public void increment(int ord, int count) {
+        counts[ord] += count;
+      }
+
+      @Override
+      public int getCount(int ord) {
+        return counts[ord];
+      }
+      
+    };
+  }
 
   @Override
   public FacetResult getTopChildren(int topN, String dim, String... path) throws IOException {
@@ -104,15 +124,16 @@ public class SortedSetDocValuesFacetCounts extends Facets {
     //System.out.println("getDim : " + ordRange.start + " - " + ordRange.end);
     for(int ord=ordRange.start; ord<=ordRange.end; ord++) {
       //System.out.println("  ord=" + ord + " count=" + counts[ord]);
-      if (counts[ord] > 0) {
-        dimCount += counts[ord];
+      int count = counter.getCount(ord);
+      if (count > 0) {
+        dimCount += count;
         childCount++;
-        if (counts[ord] > bottomCount) {
+        if (count > bottomCount) {
           if (reuse == null) {
             reuse = new TopOrdAndIntQueue.OrdAndValue();
           }
           reuse.ord = ord;
-          reuse.value = counts[ord];
+          reuse.value = count;
           if (q == null) {
             // Lazy init, so we don't create this for the
             // sparse case unnecessarily
@@ -202,8 +223,8 @@ public class SortedSetDocValuesFacetCounts extends Facets {
             segValues.setDocument(doc);
             int term = (int) segValues.nextOrd();
             while (term != SortedSetDocValues.NO_MORE_ORDS) {
-              //System.out.println("      segOrd=" + segOrd + " ord=" + term + " globalOrd=" + ordinalMap.getGlobalOrd(segOrd, term));
-              counts[(int) ordinalMap.getGlobalOrd(segOrd, term)]++;
+              //System.out.println("      segOrd=" + segOrd + " ord=" + term + " globalOrd=" + ordinalMap.getGlobalOrd(segOrd, term));              
+              counter.increment((int) ordinalMap.getGlobalOrd(segOrd, term), 1);
               term = (int) segValues.nextOrd();
             }
             ++doc;
@@ -230,8 +251,8 @@ public class SortedSetDocValuesFacetCounts extends Facets {
           for(int ord=0;ord<numSegOrds;ord++) {
             int count = segCounts[ord];
             if (count != 0) {
-              //System.out.println("    migrate segOrd=" + segOrd + " ord=" + ord + " globalOrd=" + ordinalMap.getGlobalOrd(segOrd, ord));
-              counts[(int) ordinalMap.getGlobalOrd(segOrd, ord)] += count;
+              //System.out.println("    migrate segOrd=" + segOrd + " ord=" + ord + " globalOrd=" + ordinalMap.getGlobalOrd(segOrd, ord));              
+              counter.increment((int) ordinalMap.getGlobalOrd(segOrd, ord), count);
             }
           }
         }
@@ -243,8 +264,8 @@ public class SortedSetDocValuesFacetCounts extends Facets {
         while (doc < maxDoc && (doc = hits.bits.nextSetBit(doc)) != -1) {
           segValues.setDocument(doc);
           int term = (int) segValues.nextOrd();
-          while (term != SortedSetDocValues.NO_MORE_ORDS) {
-            counts[term]++;
+          while (term != SortedSetDocValues.NO_MORE_ORDS) {            
+            counter.increment(term, 1);
             term = (int) segValues.nextOrd();
           }
           ++doc;
@@ -262,8 +283,7 @@ public class SortedSetDocValuesFacetCounts extends Facets {
     if (ord < 0) {
       return -1;
     }
-
-    return counts[ord];
+    return counter.getCount(ord);
   }
 
   @Override