HADOOP-11327. BloomFilter#not() omits the last bit, resulting in an incorrect filter. Contributed by Eric Payne

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -731,6 +731,9 @@ Release 2.7.0 - UNRELEASED
     HADOOP-10668. TestZKFailoverControllerStress#testExpireBackAndForth
     occasionally fails. (Ming Ma via cnauroth)
 
+    HADOOP-11327. BloomFilter#not() omits the last bit, resulting in an
+    incorrect filter (Eric Payne via jlowe)
+
 Release 2.6.0 - 2014-11-18
 
   INCOMPATIBLE CHANGES

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/bloom/BloomFilter.java

@@ -157,7 +157,7 @@ public class BloomFilter extends Filter {
 
   @Override
   public void not() {
-    bits.flip(0, vectorSize - 1);
+    bits.flip(0, vectorSize);
   }
 
   @Override

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/util/bloom/TestBloomFilters.java

@@ -23,6 +23,7 @@ import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
 
 import java.util.AbstractCollection;
+import java.util.BitSet;
 import java.util.Iterator;
 
 import org.apache.hadoop.util.bloom.BloomFilterCommonTester.BloomFilterTestStrategy;
@@ -237,4 +238,14 @@ public class TestBloomFilters {
                 BloomFilterTestStrategy.FILTER_AND_STRATEGY,
                 BloomFilterTestStrategy.FILTER_XOR_STRATEGY)).test();
   }
+
+  @Test
+  public void testNot() {
+    BloomFilter bf = new BloomFilter(8, 1, Hash.JENKINS_HASH);
+    bf.bits = BitSet.valueOf(new byte[] { (byte) 0x95 });
+    BitSet origBitSet = (BitSet) bf.bits.clone();
+    bf.not();
+    assertFalse("BloomFilter#not should have inverted all bits",
+                bf.bits.intersects(origBitSet));
+  }
 }