HBASE-23705 Add CellComparator to HFileContext

Codecs don't have access to what CellComparator to use.  Backfill.

M hbase-common/src/main/java/org/apache/hadoop/hbase/CellComparator.java
 Adds a new compareRows with default implementation that takes a ByteBuffer.
 Needed by the index in a block encoder implementation.

M hbase-common/src/main/java/org/apache/hadoop/hbase/CellComparatorImpl.java
 Adds implementation for meta of new compareRows method. Adds utility
 method for figuring comparator based off tablename.

M hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/AbstractDataBlockEncoder.java
M hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/BufferedDataBlockEncoder.java
M hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/RowIndexCodecV1.java
M hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/RowIndexSeekerV1.java
 Comparator is in context. Remove redundant handling.

M hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/DataBlockEncoder.java
 Comparator is in context. Remove redundant handling. Clean javadoc.

M hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/HFileBlockDecodingContext.java
 Clean javadoc.

M hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/RowIndexEncoderV1.java
 Cache context so can use it to get comparator to use later.

M hbase-common/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileContext.java
 Cache cellcomparator to use. Javdoc on diff between HFileContext and
 HFileInfo.
M hbase-common/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileContextBuilder.java
 Add CellComparator

M hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/HFileOutputFormat2.java
M hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFile.java
M hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileReaderImpl.java
M hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileWriterImpl.java
M hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFileWriter.java
 Remove comparator caching. Get from context instead.

M hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/FixedFileTrailer.java
 Skip a reflection if we can.

M hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/HFileInfo.java
 Javadoc. Removed unused filed.

hbase-common/src/main/java/org/apache/hadoop/hbase/CellComparator.java

@@ -17,8 +17,11 @@
  */
 package org.apache.hadoop.hbase;
 
+import java.nio.ByteBuffer;
 import java.util.Comparator;
 
+import org.apache.hadoop.hbase.util.ByteBufferUtils;
+import org.apache.hbase.thirdparty.com.google.common.annotations.VisibleForTesting;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.yetus.audience.InterfaceStability;
 
@@ -31,11 +34,13 @@
 public interface CellComparator extends Comparator<Cell> {
   /**
    * A comparator for ordering cells in user-space tables. Useful when writing cells in sorted
-   * order as necessary for bulk import (i.e. via MapReduce)
+   * order as necessary for bulk import (i.e. via MapReduce).
    * <p>
    * CAUTION: This comparator may provide inaccurate ordering for cells from system tables,
    * and should not be relied upon in that case.
    */
+  @VisibleForTesting
+  // For internal use, see CellComparatorImpl utility methods.
   static CellComparator getInstance() {
     return CellComparatorImpl.COMPARATOR;
   }
@@ -80,6 +85,24 @@ static CellComparator getInstance() {
    */
   int compareRows(Cell cell, byte[] bytes, int offset, int length);
 
+  /**
+   * @param row ByteBuffer that wraps a row; will read from current position and will reading all
+   *            remaining; will not disturb the ByteBuffer internal state.
+   * @return greater than 0 if leftCell is bigger, less than 0 if rightCell is bigger, 0 if both
+   *         cells are equal
+   */
+  default int compareRows(ByteBuffer row, Cell cell) {
+    if (cell instanceof ByteBufferExtendedCell) {
+      return ByteBufferUtils.compareTo(row, row.position(), row.remaining(),
+        ((ByteBufferExtendedCell) cell).getRowByteBuffer(),
+        ((ByteBufferExtendedCell) cell).getRowPosition(),
+        cell.getRowLength());
+    }
+    return ByteBufferUtils.compareTo(row, row.position(), row.remaining(),
+      cell.getRowArray(), cell.getRowOffset(),
+      cell.getRowLength());
+  }
+
   /**
    * Lexographically compares the two cells excluding the row part. It compares family, qualifier,
    * timestamp and the type

hbase-common/src/main/java/org/apache/hadoop/hbase/CellComparatorImpl.java

@@ -17,6 +17,7 @@
  */
 package org.apache.hadoop.hbase;
 
+import java.nio.ByteBuffer;
 import java.util.Comparator;
 
 import org.apache.hadoop.hbase.KeyValue.Type;
@@ -377,6 +378,27 @@ private static int compareRows(byte[] left, int loffset, int llength, byte[] rig
       return result;
     }
 
+    @Override
+    public int compareRows(ByteBuffer row, Cell cell) {
+      byte [] array;
+      int offset;
+      int len = row.remaining();
+      if (row.hasArray()) {
+        array = row.array();
+        offset = row.position() + row.arrayOffset();
+      } else {
+        // This is awful, we copy the row array if offheap just so we can do a compare.
+        // We do this elsewhere too when Cell is backed by an offheap ByteBuffer.
+        // Needs fixing. TODO.
+        array = new byte[len];
+        offset = 0;
+        ByteBufferUtils.copyFromBufferToArray(array, row, row.position(),
+          0, len);
+      }
+      // Reverse result since we swap the order of the params we pass below.
+      return -compareRows(cell, array, offset, len);
+    }
+
     @Override
     public Comparator getSimpleComparator() {
       return this;
@@ -387,4 +409,23 @@ public Comparator getSimpleComparator() {
   public Comparator getSimpleComparator() {
     return new BBKVComparator(this);
   }
+
+  /**
+   * Utility method that makes a guess at comparator to use based off passed tableName.
+   * Use in extreme when no comparator specified.
+   * @return CellComparator to use going off the <code>tableName</code> passed.
+   */
+  public static CellComparator getCellComparator(TableName tableName) {
+    return getCellComparator(tableName.toBytes());
+  }
+
+  /**
+   * Utility method that makes a guess at comparator to use based off passed tableName.
+   * Use in extreme when no comparator specified.
+   * @return CellComparator to use going off the <code>tableName</code> passed.
+   */
+  public static CellComparator getCellComparator(byte [] tableName) {
+    return tableName.equals(TableName.META_TABLE_NAME.toBytes())?
+      CellComparatorImpl.COMPARATOR: CellComparatorImpl.META_COMPARATOR;
+  }
 }

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/AbstractDataBlockEncoder.java

@@ -21,7 +21,6 @@
 
 import org.apache.hadoop.hbase.ByteBufferKeyOnlyKeyValue;
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellComparator;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.io.hfile.BlockType;
 import org.apache.hadoop.hbase.io.hfile.HFileContext;
@@ -59,14 +58,13 @@ protected Cell createFirstKeyCell(ByteBuffer key, int keyLength) {
     }
   }
 
-  protected abstract static class AbstractEncodedSeeker implements
-      EncodedSeeker {
+  /**
+   * Decorates EncodedSeeker with a {@link HFileBlockDecodingContext}
+   */
+  protected abstract static class AbstractEncodedSeeker implements EncodedSeeker {
     protected HFileBlockDecodingContext decodingCtx;
-    protected final CellComparator comparator;
 
-    public AbstractEncodedSeeker(CellComparator comparator,
-        HFileBlockDecodingContext decodingCtx) {
-      this.comparator = comparator;
+    public AbstractEncodedSeeker(HFileBlockDecodingContext decodingCtx) {
       this.decodingCtx = decodingCtx;
     }
 
@@ -77,7 +75,5 @@ protected boolean includesMvcc() {
     protected boolean includesTags() {
       return this.decodingCtx.getHFileContext().isIncludesTags();
     }
-
   }
-
 }

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/BufferedDataBlockEncoder.java

@@ -732,9 +732,8 @@ protected abstract static class BufferedEncodedSeeker<STATE extends SeekerState>
     protected final ObjectIntPair<ByteBuffer> tmpPair = new ObjectIntPair<>();
     protected STATE current, previous;
 
-    public BufferedEncodedSeeker(CellComparator comparator,
-        HFileBlockDecodingContext decodingCtx) {
-      super(comparator, decodingCtx);
+    public BufferedEncodedSeeker(HFileBlockDecodingContext decodingCtx) {
+      super(decodingCtx);
       if (decodingCtx.getHFileContext().isCompressTags()) {
         try {
           tagCompressionContext = new TagCompressionContext(LRUDictionary.class, Byte.MAX_VALUE);

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/CopyKeyDataBlockEncoder.java

@@ -22,7 +22,6 @@
 import java.nio.ByteBuffer;
 
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellComparator;
 import org.apache.hadoop.hbase.nio.ByteBuff;
 import org.apache.hadoop.hbase.util.ByteBufferUtils;
 import org.apache.hadoop.hbase.util.Bytes;
@@ -81,9 +80,8 @@ public String toString() {
   }
 
   @Override
-  public EncodedSeeker createSeeker(CellComparator comparator,
-      final HFileBlockDecodingContext decodingCtx) {
-    return new BufferedEncodedSeeker<SeekerState>(comparator, decodingCtx) {
+  public EncodedSeeker createSeeker(final HFileBlockDecodingContext decodingCtx) {
+    return new BufferedEncodedSeeker<SeekerState>(decodingCtx) {
       @Override
       protected void decodeNext() {
         current.keyLength = currentBuffer.getInt();

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/DataBlockEncoder.java

@@ -45,39 +45,27 @@ public interface DataBlockEncoder {
    * Starts encoding for a block of KeyValues. Call
    * {@link #endBlockEncoding(HFileBlockEncodingContext, DataOutputStream, byte[])} to finish
    * encoding of a block.
-   * @param encodingCtx
-   * @param out
-   * @throws IOException
    */
   void startBlockEncoding(HFileBlockEncodingContext encodingCtx, DataOutputStream out)
       throws IOException;
 
   /**
    * Encodes a KeyValue.
-   * @param cell
-   * @param encodingCtx
-   * @param out
    * @return unencoded kv size written
-   * @throws IOException
    */
   int encode(Cell cell, HFileBlockEncodingContext encodingCtx, DataOutputStream out)
       throws IOException;
 
   /**
    * Ends encoding for a block of KeyValues. Gives a chance for the encoder to do the finishing
    * stuff for the encoded block. It must be called at the end of block encoding.
-   * @param encodingCtx
-   * @param out
-   * @param uncompressedBytesWithHeader
-   * @throws IOException
    */
   void endBlockEncoding(HFileBlockEncodingContext encodingCtx, DataOutputStream out,
       byte[] uncompressedBytesWithHeader) throws IOException;
 
   /**
    * Decode.
    * @param source Compressed stream of KeyValues.
-   * @param decodingCtx
    * @return Uncompressed block of KeyValues.
    * @throws IOException If there is an error in source.
    */
@@ -96,11 +84,9 @@ ByteBuffer decodeKeyValues(DataInputStream source, HFileBlockDecodingContext dec
 
   /**
    * Create a HFileBlock seeker which find KeyValues within a block.
-   * @param comparator what kind of comparison should be used
-   * @param decodingCtx
    * @return A newly created seeker.
    */
-  EncodedSeeker createSeeker(CellComparator comparator, HFileBlockDecodingContext decodingCtx);
+  EncodedSeeker createSeeker(HFileBlockDecodingContext decodingCtx);
 
   /**
    * Creates a encoder specific encoding context

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/DiffKeyDeltaEncoder.java

@@ -22,7 +22,6 @@
 import java.nio.ByteBuffer;
 
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellComparator;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.PrivateCellUtil;
@@ -382,9 +381,8 @@ protected void copyFromNext(SeekerState that) {
   }
 
   @Override
-  public EncodedSeeker createSeeker(CellComparator comparator,
-      HFileBlockDecodingContext decodingCtx) {
-    return new BufferedEncodedSeeker<DiffSeekerState>(comparator, decodingCtx) {
+  public EncodedSeeker createSeeker(HFileBlockDecodingContext decodingCtx) {
+    return new BufferedEncodedSeeker<DiffSeekerState>(decodingCtx) {
       private byte[] familyNameWithSize;
       private static final int TIMESTAMP_WITH_TYPE_LENGTH =
           Bytes.SIZEOF_LONG + Bytes.SIZEOF_BYTE;

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/FastDiffDeltaEncoder.java

@@ -23,7 +23,6 @@
 import java.nio.ByteBuffer;
 
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellComparator;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.PrivateCellUtil;
@@ -397,9 +396,8 @@ protected void copyFromNext(SeekerState that) {
   }
 
   @Override
-  public EncodedSeeker createSeeker(CellComparator comparator,
-      final HFileBlockDecodingContext decodingCtx) {
-    return new BufferedEncodedSeeker<FastDiffSeekerState>(comparator, decodingCtx) {
+  public EncodedSeeker createSeeker(final HFileBlockDecodingContext decodingCtx) {
+    return new BufferedEncodedSeeker<FastDiffSeekerState>(decodingCtx) {
       private void decode(boolean isFirst) {
         byte flag = currentBuffer.get();
         if ((flag & FLAG_SAME_KEY_LENGTH) == 0) {

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/HFileBlockDecodingContext.java

@@ -24,13 +24,12 @@
 
 /**
  * A decoding context that is created by a reader's encoder, and is shared
- * across the reader's all read operations.
+ * across all of the reader's read operations.
  *
  * @see HFileBlockEncodingContext for encoding
  */
 @InterfaceAudience.Private
 public interface HFileBlockDecodingContext {
-
   /**
    * Perform all actions that need to be done before the encoder's real decoding
    * process. Decompression needs to be done if
@@ -46,7 +45,6 @@ public interface HFileBlockDecodingContext {
    *          ByteBuffer pointed after the header but before the data
    * @param onDiskBlock
    *          on disk data to be decoded
-   * @throws IOException
    */
   void prepareDecoding(
     int onDiskSizeWithoutHeader,

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/HFileBlockDefaultDecodingContext.java

@@ -41,11 +41,10 @@
  *
  */
 @InterfaceAudience.Private
-public class HFileBlockDefaultDecodingContext implements
-    HFileBlockDecodingContext {
+public class HFileBlockDefaultDecodingContext implements HFileBlockDecodingContext {
   private final HFileContext fileContext;
   private TagCompressionContext tagCompressionContext;
-  
+
   public HFileBlockDefaultDecodingContext(HFileContext fileContext) {
     this.fileContext = fileContext;
   }

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/HFileBlockDefaultEncodingContext.java

@@ -47,8 +47,7 @@
  *
  */
 @InterfaceAudience.Private
-public class HFileBlockDefaultEncodingContext implements
-    HFileBlockEncodingContext {
+public class HFileBlockDefaultEncodingContext implements HFileBlockEncodingContext {
   private BlockType blockType;
   private final DataBlockEncoding encodingAlgo;
 

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/HFileBlockEncodingContext.java

@@ -46,9 +46,6 @@ public interface HFileBlockEncodingContext {
   /**
    * Do any action that needs to be performed after the encoding.
    * Compression is also included if a non-null compression algorithm is used
-   *
-   * @param blockType
-   * @throws IOException
    */
   void postEncoding(BlockType blockType) throws IOException;
 
@@ -64,7 +61,6 @@ public interface HFileBlockEncodingContext {
 
   /**
    * Sets the encoding state.
-   * @param state
    */
   void setEncodingState(EncodingState state);
 

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/PrefixKeyDeltaEncoder.java

@@ -23,7 +23,6 @@
 import java.nio.ByteBuffer;
 
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellComparator;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.PrivateCellUtil;
@@ -195,9 +194,8 @@ public String toString() {
   }
 
   @Override
-  public EncodedSeeker createSeeker(CellComparator comparator,
-      final HFileBlockDecodingContext decodingCtx) {
-    return new BufferedEncodedSeeker<SeekerState>(comparator, decodingCtx) {
+  public EncodedSeeker createSeeker(final HFileBlockDecodingContext decodingCtx) {
+    return new BufferedEncodedSeeker<SeekerState>(decodingCtx) {
       @Override
       protected void decodeNext() {
         current.keyLength = ByteBuff.readCompressedInt(currentBuffer);

hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/RowIndexCodecV1.java

@@ -24,8 +24,6 @@
 import java.util.List;
 
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.CellComparator;
-import org.apache.hadoop.hbase.CellComparatorImpl;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.io.ByteArrayOutputStream;
@@ -115,8 +113,7 @@ public ByteBuffer decodeKeyValues(DataInputStream source,
       dup.limit(sourceAsBuffer.position() + onDiskSize);
       return dup.slice();
     } else {
-      RowIndexSeekerV1 seeker = new RowIndexSeekerV1(CellComparatorImpl.COMPARATOR,
-          decodingCtx);
+      RowIndexSeekerV1 seeker = new RowIndexSeekerV1(decodingCtx);
       seeker.setCurrentBuffer(new SingleByteBuff(sourceAsBuffer));
       List<Cell> kvs = new ArrayList<>();
       kvs.add(seeker.getCell());
@@ -151,9 +148,7 @@ public Cell getFirstKeyCellInBlock(ByteBuff block) {
   }
 
   @Override
-  public EncodedSeeker createSeeker(CellComparator comparator,
-      HFileBlockDecodingContext decodingCtx) {
-    return new RowIndexSeekerV1(comparator, decodingCtx);
+  public EncodedSeeker createSeeker(HFileBlockDecodingContext decodingCtx) {
+    return new RowIndexSeekerV1(decodingCtx);
   }
-
 }