Index: solr/core/src/java/org/apache/solr/search/MissingStringLastComparatorSource.java
===================================================================
--- solr/core/src/java/org/apache/solr/search/MissingStringLastComparatorSource.java	(revision 1180735)
+++ solr/core/src/java/org/apache/solr/search/MissingStringLastComparatorSource.java	(working copy)
@@ -24,9 +24,6 @@
 import org.apache.lucene.search.FieldComparatorSource;
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.UnicodeUtil;
-import org.apache.lucene.util.packed.Direct16;
-import org.apache.lucene.util.packed.Direct32;
-import org.apache.lucene.util.packed.Direct8;
 import org.apache.lucene.util.packed.PackedInts;
 
 import java.io.IOException;
@@ -438,15 +435,19 @@
   public static FieldComparator createComparator(IndexReader reader, TermOrdValComparator_SML parent) throws IOException {
     parent.termsIndex = FieldCache.DEFAULT.getTermsIndex(reader, parent.field);
     final PackedInts.Reader docToOrd = parent.termsIndex.getDocToOrd();
-    PerSegmentComparator perSegComp;
+    PerSegmentComparator perSegComp = null;
+    if (docToOrd.hasArray()) {
+      final Object arr = docToOrd.getArray();
+      if (arr instanceof byte[]) {
+        perSegComp = new ByteOrdComparator((byte[]) arr, parent);
+      } else if (arr instanceof short[]) {
+        perSegComp = new ShortOrdComparator((short[]) arr, parent);
+      } else if (arr instanceof int[]) {
+        perSegComp = new IntOrdComparator((int[]) arr, parent);
+      }
+    }
 
-    if (docToOrd instanceof Direct8) {
-      perSegComp = new ByteOrdComparator(((Direct8) docToOrd).getArray(), parent);
-    } else if (docToOrd instanceof Direct16) {
-      perSegComp = new ShortOrdComparator(((Direct16) docToOrd).getArray(), parent);
-    } else if (docToOrd instanceof Direct32) {
-      perSegComp = new IntOrdComparator(((Direct32) docToOrd).getArray(), parent);
-    } else {
+    if (perSegComp == null) {
       perSegComp = new AnyOrdComparator(docToOrd, parent);
     }
 
Index: solr/core/src/java/org/apache/solr/request/SimpleFacets.java
===================================================================
--- solr/core/src/java/org/apache/solr/request/SimpleFacets.java	(revision 1180735)
+++ solr/core/src/java/org/apache/solr/request/SimpleFacets.java	(working copy)
@@ -22,9 +22,6 @@
 import org.apache.lucene.search.*;
 import org.apache.lucene.search.grouping.AbstractAllGroupHeadsCollector;
 import org.apache.lucene.util.*;
-import org.apache.lucene.util.packed.Direct16;
-import org.apache.lucene.util.packed.Direct32;
-import org.apache.lucene.util.packed.Direct8;
 import org.apache.lucene.util.packed.PackedInts;
 import org.apache.solr.common.SolrException;
 import org.apache.solr.common.SolrException.ErrorCode;
@@ -450,8 +447,15 @@
       DocIterator iter = docs.iterator();
 
       PackedInts.Reader ordReader = si.getDocToOrd();
-      if (ordReader instanceof Direct32) {
-        int[] ords = ((Direct32)ordReader).getArray();
+      final Object arr;
+      if (ordReader.hasArray()) {
+        arr = ordReader.getArray();
+      } else {
+        arr = null;
+      }
+
+      if (arr instanceof int[]) {
+        int[] ords = (int[]) arr;
         if (prefix==null) {
           while (iter.hasNext()) {
             counts[ords[iter.nextDoc()]]++;
@@ -463,8 +467,8 @@
             if (arrIdx>=0 && arrIdx<nTerms) counts[arrIdx]++;
           }
         }
-      } else if (ordReader instanceof Direct16) {
-        short[] ords = ((Direct16)ordReader).getArray();
+      } else if (arr instanceof short[]) {
+        short[] ords = (short[]) arr;
         if (prefix==null) {
           while (iter.hasNext()) {
             counts[ords[iter.nextDoc()] & 0xffff]++;
@@ -476,8 +480,8 @@
             if (arrIdx>=0 && arrIdx<nTerms) counts[arrIdx]++;
           }
         }
-      } else if (ordReader instanceof Direct8) {
-        byte[] ords = ((Direct8)ordReader).getArray();
+      } else if (arr instanceof byte[]) {
+        byte[] ords = (byte[]) arr;
         if (prefix==null) {
           while (iter.hasNext()) {
             counts[ords[iter.nextDoc()] & 0xff]++;
Index: solr/core/src/java/org/apache/solr/request/PerSegmentSingleValuedFaceting.java
===================================================================
--- solr/core/src/java/org/apache/solr/request/PerSegmentSingleValuedFaceting.java	(revision 1180735)
+++ solr/core/src/java/org/apache/solr/request/PerSegmentSingleValuedFaceting.java	(working copy)
@@ -28,9 +28,6 @@
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.ReaderUtil;
 import org.apache.lucene.util.UnicodeUtil;
-import org.apache.lucene.util.packed.Direct16;
-import org.apache.lucene.util.packed.Direct32;
-import org.apache.lucene.util.packed.Direct8;
 import org.apache.lucene.util.packed.PackedInts;
 import org.apache.solr.common.SolrException;
 import org.apache.solr.common.params.FacetParams;
@@ -268,8 +265,15 @@
         PackedInts.Reader ordReader = si.getDocToOrd();
         int doc;
 
-        if (ordReader instanceof Direct32) {
-          int[] ords = ((Direct32)ordReader).getArray();
+        final Object arr;
+        if (ordReader.hasArray()) {
+          arr = ordReader.getArray();
+        } else {
+          arr = null;
+        }
+
+        if (arr instanceof int[]) {
+          int[] ords = (int[]) arr;
           if (prefix==null) {
             while ((doc = iter.nextDoc()) < DocIdSetIterator.NO_MORE_DOCS) {
               counts[ords[doc]]++;
@@ -281,8 +285,8 @@
               if (arrIdx>=0 && arrIdx<nTerms) counts[arrIdx]++;
             }
           }
-        } else if (ordReader instanceof Direct16) {
-          short[] ords = ((Direct16)ordReader).getArray();
+        } else if (arr instanceof short[]) {
+          short[] ords = (short[]) arr;
           if (prefix==null) {
             while ((doc = iter.nextDoc()) < DocIdSetIterator.NO_MORE_DOCS) {
               counts[ords[doc] & 0xffff]++;
@@ -294,8 +298,8 @@
               if (arrIdx>=0 && arrIdx<nTerms) counts[arrIdx]++;
             }
           }
-        } else if (ordReader instanceof Direct8) {
-          byte[] ords = ((Direct8)ordReader).getArray();
+        } else if (arr instanceof byte[]) {
+          byte[] ords = (byte[]) arr;
           if (prefix==null) {
             while ((doc = iter.nextDoc()) < DocIdSetIterator.NO_MORE_DOCS) {
               counts[ords[doc] & 0xff]++;
@@ -322,7 +326,6 @@
             }
           }
         }
-
       }
     }
   }
Index: lucene/src/java/org/apache/lucene/search/FieldComparator.java
===================================================================
--- lucene/src/java/org/apache/lucene/search/FieldComparator.java	(revision 1180859)
+++ lucene/src/java/org/apache/lucene/search/FieldComparator.java	(working copy)
@@ -26,9 +26,6 @@
 import org.apache.lucene.search.cache.CachedArray.*;
 import org.apache.lucene.util.Bits;
 import org.apache.lucene.util.BytesRef;
-import org.apache.lucene.util.packed.Direct16;
-import org.apache.lucene.util.packed.Direct32;
-import org.apache.lucene.util.packed.Direct8;
 import org.apache.lucene.util.packed.PackedInts;
 
 import java.io.IOException;
@@ -1222,14 +1219,21 @@
       final int docBase = context.docBase;
       termsIndex = FieldCache.DEFAULT.getTermsIndex(context.reader, field);
       final PackedInts.Reader docToOrd = termsIndex.getDocToOrd();
-      FieldComparator perSegComp;
-      if (docToOrd instanceof Direct8) {
-        perSegComp = new ByteOrdComparator(((Direct8) docToOrd).getArray(), termsIndex, docBase);
-      } else if (docToOrd instanceof Direct16) {
-        perSegComp = new ShortOrdComparator(((Direct16) docToOrd).getArray(), termsIndex, docBase);
-      } else if (docToOrd instanceof Direct32) {
-        perSegComp = new IntOrdComparator(((Direct32) docToOrd).getArray(), termsIndex, docBase);
-      } else {
+      FieldComparator perSegComp = null;
+      if (docToOrd.hasArray()) {
+        final Object arr = docToOrd.getArray();
+        if (arr instanceof byte[]) {
+          perSegComp = new ByteOrdComparator((byte[]) arr, termsIndex, docBase);
+        } else if (arr instanceof short[]) {
+          perSegComp = new ShortOrdComparator((short[]) arr, termsIndex, docBase);
+        } else if (arr instanceof int[]) {
+          perSegComp = new IntOrdComparator((int[]) arr, termsIndex, docBase);
+        }
+        // Don't specialize the long[] case since it's not
+        // possible, ie, worse case is MAX_INT-1 docs with
+        // every one having a unique value.
+      }
+      if (perSegComp == null) {
         perSegComp = new AnyOrdComparator(docToOrd, termsIndex, docBase);
       }
 
Index: lucene/src/java/org/apache/lucene/util/packed/Direct32.java
===================================================================
--- lucene/src/java/org/apache/lucene/util/packed/Direct32.java	(revision 1180859)
+++ lucene/src/java/org/apache/lucene/util/packed/Direct32.java	(working copy)
@@ -28,7 +28,7 @@
  * @lucene.internal
  */
 
-public class Direct32 extends PackedInts.ReaderImpl
+class Direct32 extends PackedInts.ReaderImpl
         implements PackedInts.Mutable {
   private int[] values;
   private static final int BITS_PER_VALUE = 32;
@@ -64,10 +64,6 @@
     this.values = values;
   }
 
-  public int[] getArray() {
-    return values;
-  }
-
   public long get(final int index) {
     return 0xFFFFFFFFL & values[index];
   }
@@ -84,4 +80,14 @@
   public void clear() {
     Arrays.fill(values, 0);
   }
+  
+  @Override
+  public int[] getArray() {
+    return values;
+  }
+
+  @Override
+  public boolean hasArray() {
+    return true;
+  }
 }
Index: lucene/src/java/org/apache/lucene/util/packed/GrowableWriter.java
===================================================================
--- lucene/src/java/org/apache/lucene/util/packed/GrowableWriter.java	(revision 1180859)
+++ lucene/src/java/org/apache/lucene/util/packed/GrowableWriter.java	(working copy)
@@ -60,6 +60,16 @@
     return current;
   }
 
+  @Override
+  public Object getArray() {
+    return current.getArray();
+  }
+
+  @Override
+  public boolean hasArray() {
+    return current.hasArray();
+  }
+
   public void set(int index, long value) {
     if (value >= currentMaxValue) {
       int bpv = getBitsPerValue();
Index: lucene/src/java/org/apache/lucene/util/packed/Direct16.java
===================================================================
--- lucene/src/java/org/apache/lucene/util/packed/Direct16.java	(revision 1180859)
+++ lucene/src/java/org/apache/lucene/util/packed/Direct16.java	(working copy)
@@ -28,7 +28,7 @@
  * @lucene.internal
  */
 
-public class Direct16 extends PackedInts.ReaderImpl
+class Direct16 extends PackedInts.ReaderImpl
         implements PackedInts.Mutable {
   private short[] values;
   private static final int BITS_PER_VALUE = 16;
@@ -68,10 +68,6 @@
     this.values = values;
   }
 
-  public short[] getArray() {
-    return values;
-  }
-
   public long get(final int index) {
     return 0xFFFFL & values[index];
   }
@@ -88,4 +84,14 @@
   public void clear() {
     Arrays.fill(values, (short)0);
   }
+
+  @Override
+  public Object getArray() {
+    return values;
+  }
+
+  @Override
+  public boolean hasArray() {
+    return true;
+  }
 }
Index: lucene/src/java/org/apache/lucene/util/packed/Direct8.java
===================================================================
--- lucene/src/java/org/apache/lucene/util/packed/Direct8.java	(revision 1180859)
+++ lucene/src/java/org/apache/lucene/util/packed/Direct8.java	(working copy)
@@ -28,7 +28,7 @@
  * @lucene.internal
  */
 
-public class Direct8 extends PackedInts.ReaderImpl
+class Direct8 extends PackedInts.ReaderImpl
         implements PackedInts.Mutable {
   private byte[] values;
   private static final int BITS_PER_VALUE = 8;
@@ -69,10 +69,6 @@
     this.values = values;
   }
 
-  public byte[] getArray() {
-    return values;
-  }
-
   public long get(final int index) {
     return 0xFFL & values[index];
   }
@@ -88,4 +84,14 @@
   public void clear() {
     Arrays.fill(values, (byte)0);
   }
+
+  @Override
+  public Object getArray() {
+    return values;
+  }
+
+  @Override
+  public boolean hasArray() {
+    return true;
+  }
 }
Index: lucene/src/java/org/apache/lucene/util/packed/Direct64.java
===================================================================
--- lucene/src/java/org/apache/lucene/util/packed/Direct64.java	(revision 1180859)
+++ lucene/src/java/org/apache/lucene/util/packed/Direct64.java	(working copy)
@@ -28,7 +28,7 @@
  * @lucene.internal
  */
 
-public class Direct64 extends PackedInts.ReaderImpl
+class Direct64 extends PackedInts.ReaderImpl
         implements PackedInts.Mutable {
   private long[] values;
   private static final int BITS_PER_VALUE = 64;
@@ -48,10 +48,6 @@
     this.values = values;
   }
 
-  public long[] getArray() {
-    return values;
-  }
-
   /**
    * Creates an array backed by the given values.
    * </p><p>
@@ -80,4 +76,14 @@
   public void clear() {
     Arrays.fill(values, 0L);
   }
+
+  @Override
+  public long[] getArray() {
+    return values;
+  }
+
+  @Override
+  public boolean hasArray() {
+    return true;
+  }
 }
Index: lucene/src/java/org/apache/lucene/util/packed/PackedInts.java
===================================================================
--- lucene/src/java/org/apache/lucene/util/packed/PackedInts.java	(revision 1180859)
+++ lucene/src/java/org/apache/lucene/util/packed/PackedInts.java	(working copy)
@@ -65,6 +65,25 @@
      * @return the number of values.
      */
     int size();
+
+    /**
+     * Expert: if the bit-width of this reader matches one of
+     * java's native types, returns the underlying array
+     * (ie, byte[], short[], int[], long[]); else, returns
+     * null.  Note that when accessing the array you must
+     * upgrade the type (bitwise AND with all ones), to
+     * interpret the full value as unsigned.  Ie,
+     * bytes[idx]&0xFF, shorts[idx]&0xFFFF, etc.
+     */
+    Object getArray();
+
+    /**
+     * Returns true if this implementation is backed by a
+     * native java array.
+     *
+     * @see #getArray
+     */
+    boolean hasArray();
   }
 
   /**
@@ -137,6 +156,14 @@
     public long getMaxValue() { // Convenience method
       return maxValue(bitsPerValue);
     }
+
+    public Object getArray() {
+      return null;
+    }
+
+    public boolean hasArray() {
+      return false;
+    }
   }
 
   /** A write-once Writer.