HBASE-12078 Missing Data when scanning using PREFIX_TREE DATA-BLOCK-ENCODING

Signed-off-by: Andrew Purtell <apurtell@apache.org>

hbase-prefix-tree/src/main/java/org/apache/hadoop/hbase/codec/prefixtree/decode/PrefixTreeArraySearcher.java

@@ -93,7 +93,7 @@ public class PrefixTreeArraySearcher extends PrefixTreeArrayReversibleScanner im
       byte searchForByte = CellUtil.getRowByte(key, currentNodeDepth);
       fanIndex = currentRowNode.whichFanNode(searchForByte);
       if(fanIndex < 0){//no matching row.  return early
-        int insertionPoint = -fanIndex;
+        int insertionPoint = -fanIndex - 1;
         return fixRowFanMissReverse(insertionPoint);
       }
       //found a match, so dig deeper into the tree
@@ -142,7 +142,7 @@ public class PrefixTreeArraySearcher extends PrefixTreeArrayReversibleScanner im
       byte searchForByte = CellUtil.getRowByte(key, currentNodeDepth);
       fanIndex = currentRowNode.whichFanNode(searchForByte);
       if(fanIndex < 0){//no matching row.  return early
-        int insertionPoint = -fanIndex;
+        int insertionPoint = -fanIndex - 1;
         return fixRowFanMissForward(insertionPoint);
       }
       //found a match, so dig deeper into the tree
@@ -293,6 +293,9 @@ public class PrefixTreeArraySearcher extends PrefixTreeArrayReversibleScanner im
       }
       return UnsignedBytes.compare(keyByte, thisByte);
     }
+    if (!currentRowNode.hasOccurrences() && rowLength >= key.getRowLength()) { // key was shorter
+        return -1;
+    }
     return 0;
   }
 
@@ -366,6 +369,10 @@ public class PrefixTreeArraySearcher extends PrefixTreeArrayReversibleScanner im
 
   protected CellScannerPosition fixRowFanMissReverse(int fanInsertionPoint){
     if(fanInsertionPoint == 0){//we need to back up a row
+      if (currentRowNode.hasOccurrences()) {
+        populateLastNonRowFields();
+        return CellScannerPosition.BEFORE;
+      }
       boolean foundPreviousRow = previousRow(true);//true -> position on last cell in row
       if(foundPreviousRow){
         populateLastNonRowFields();

hbase-prefix-tree/src/main/java/org/apache/hadoop/hbase/codec/prefixtree/decode/row/RowNodeReader.java

@@ -232,7 +232,7 @@ public class RowNodeReader {
     if (fanIndexInBlock >= 0) {// found it, but need to adjust for position of fan in overall block
       return fanIndexInBlock - fanOffset;
     }
-    return fanIndexInBlock + fanOffset + 1;// didn't find it, so compensate in reverse
+    return fanIndexInBlock + fanOffset;// didn't find it, so compensate in reverse
   }
 
   public void resetFanIndex() {

hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/TestPrefixTreeSearcher.java

@@ -21,6 +21,7 @@ package org.apache.hadoop.hbase.codec.prefixtree.row;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.nio.ByteBuffer;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 
@@ -31,6 +32,7 @@ import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.SmallTests;
 import org.apache.hadoop.hbase.codec.prefixtree.decode.DecoderFactory;
 import org.apache.hadoop.hbase.codec.prefixtree.encode.PrefixTreeEncoder;
+import org.apache.hadoop.hbase.codec.prefixtree.row.data.TestRowDataSearchWithPrefix;
 import org.apache.hadoop.hbase.codec.prefixtree.scanner.CellScannerPosition;
 import org.apache.hadoop.hbase.codec.prefixtree.scanner.CellSearcher;
 import org.apache.hadoop.hbase.util.CollectionUtils;
@@ -67,7 +69,6 @@ public class TestPrefixTreeSearcher {
     this.block = ByteBuffer.wrap(outputBytes);
   }
 
-
   @Test
   public void testScanForwards() throws IOException {
     CellSearcher searcher = null;
@@ -196,4 +197,25 @@ public class TestPrefixTreeSearcher {
       DecoderFactory.checkIn(searcher);
     }
   }
+  
+  @Test
+  public void testSeekWithPrefix() throws IOException {
+    if (!(rows instanceof TestRowDataSearchWithPrefix)) {
+      return;
+    }
+    CellSearcher searcher = null;
+    try {
+      searcher = DecoderFactory.checkOut(block, true);
+      // seek with half bytes of second row key, should return second row
+      KeyValue kv = rows.getInputs().get(1);
+      KeyValue firstKVOnRow = KeyValueUtil.createFirstOnRow(Arrays.copyOfRange(
+          kv.getRowArray(), kv.getRowOffset(),
+          kv.getRowOffset() + kv.getRowLength() / 2));
+      CellScannerPosition position = searcher.positionAtOrAfter(firstKVOnRow);
+      Assert.assertEquals(CellScannerPosition.AFTER, position);
+      Assert.assertEquals(kv, searcher.current());
+    } finally {
+      DecoderFactory.checkIn(searcher);
+    }
+  }
 }

hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/TestRowData.java

@@ -33,6 +33,7 @@ import org.apache.hadoop.hbase.codec.prefixtree.row.data.TestRowDataNumberString
 import org.apache.hadoop.hbase.codec.prefixtree.row.data.TestRowDataQualifierByteOrdering;
 import org.apache.hadoop.hbase.codec.prefixtree.row.data.TestRowDataRandomKeyValues;
 import org.apache.hadoop.hbase.codec.prefixtree.row.data.TestRowDataRandomKeyValuesWithTags;
+import org.apache.hadoop.hbase.codec.prefixtree.row.data.TestRowDataSearchWithPrefix;
 import org.apache.hadoop.hbase.codec.prefixtree.row.data.TestRowDataSearcherRowMiss;
 import org.apache.hadoop.hbase.codec.prefixtree.row.data.TestRowDataSimple;
 import org.apache.hadoop.hbase.codec.prefixtree.row.data.TestRowDataSingleQualifier;
@@ -87,6 +88,9 @@ public interface TestRowData {
       all.add(new TestRowDataExerciseFInts());
       all.add(new TestRowDataRandomKeyValues());
       all.add(new TestRowDataRandomKeyValuesWithTags());
+      
+      //test data for HBase-12078
+      all.add(new TestRowDataSearchWithPrefix());
       return all;
     }
 

hbase-prefix-tree/src/test/java/org/apache/hadoop/hbase/codec/prefixtree/row/data/TestRowDataSearchWithPrefix.java

@@ -0,0 +1,74 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.hbase.codec.prefixtree.row.data;
+
+import java.io.ByteArrayOutputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.List;
+
+import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.codec.prefixtree.row.BaseTestRowData;
+import org.apache.hadoop.hbase.util.Bytes;
+
+import com.google.common.collect.Lists;
+
+public class TestRowDataSearchWithPrefix extends BaseTestRowData {
+
+  static byte[] cf = Bytes.toBytes("cf");
+
+  static byte[] cq = Bytes.toBytes("cq");
+
+  static byte[] v = Bytes.toBytes("v");
+
+  static List<KeyValue> d = Lists.newArrayList();
+
+  static long ts = 55L;
+
+  static byte[] createRowKey(int keyPart1, int keyPart2) {
+    ByteArrayOutputStream bos = new ByteArrayOutputStream(16);
+    DataOutputStream dos = new DataOutputStream(bos);
+    try {
+      dos.writeInt(keyPart1);
+      dos.writeInt(keyPart2);
+    } catch (IOException e) {
+      // should not happen
+      throw new RuntimeException(e);
+    }
+
+    return bos.toByteArray();
+  }
+
+  static {
+    d.add(new KeyValue(createRowKey(1, 12345), cf, cq, ts, v));
+    d.add(new KeyValue(createRowKey(12345, 0x01000000), cf, cq, ts, v));
+    d.add(new KeyValue(createRowKey(12345, 0x01010000), cf, cq, ts, v));
+    d.add(new KeyValue(createRowKey(12345, 0x02000000), cf, cq, ts, v));
+    d.add(new KeyValue(createRowKey(12345, 0x02020000), cf, cq, ts, v));
+    d.add(new KeyValue(createRowKey(12345, 0x03000000), cf, cq, ts, v));
+    d.add(new KeyValue(createRowKey(12345, 0x03030000), cf, cq, ts, v));
+    d.add(new KeyValue(createRowKey(12345, 0x04000000), cf, cq, ts, v));
+    d.add(new KeyValue(createRowKey(12345, 0x04040000), cf, cq, ts, v));
+  }
+
+  @Override
+  public List<KeyValue> getInputs() {
+    return d;
+  }
+
+}