Java ByteBufferUtils.copyFromStreamToBuffer方法代码示例

import org.apache.hadoop.hbase.util.ByteBufferUtils; //导入方法依赖的package包/类
@Override
protected ByteBuffer internalDecodeKeyValues(DataInputStream source, int allocateHeaderLength,
    int skipLastBytes, HFileBlockDefaultDecodingContext decodingCtx) throws IOException {
  int decompressedSize = source.readInt();
  ByteBuffer buffer = ByteBuffer.allocate(decompressedSize +
      allocateHeaderLength);
  buffer.position(allocateHeaderLength);
  ByteBufferUtils.copyFromStreamToBuffer(buffer, source, decompressedSize);

  return buffer;
}
 

import org.apache.hadoop.hbase.util.ByteBufferUtils; //导入方法依赖的package包/类
/**
 * Copies the first key/value from the given stream, and initializes
 * decompression state based on it. Assumes that we have already read key
 * and value lengths. Does not set {@link #qualifierLength} (not used by
 * decompression) or {@link #prevOffset} (set by the calle afterwards).
 */
private void decompressFirstKV(ByteBuffer out, DataInputStream in)
    throws IOException {
  int kvPos = out.position();
  out.putInt(keyLength);
  out.putInt(valueLength);
  prevTimestampOffset = out.position() + keyLength -
      KeyValue.TIMESTAMP_TYPE_SIZE;
  ByteBufferUtils.copyFromStreamToBuffer(out, in, keyLength + valueLength);
  rowLength = out.getShort(kvPos + KeyValue.ROW_OFFSET);
  familyLength = out.get(kvPos + KeyValue.ROW_OFFSET +
      KeyValue.ROW_LENGTH_SIZE + rowLength);
  type = out.get(prevTimestampOffset + KeyValue.TIMESTAMP_SIZE);
}
 

import org.apache.hadoop.hbase.util.ByteBufferUtils; //导入方法依赖的package包/类
protected final void afterDecodingKeyValue(DataInputStream source,
    ByteBuffer dest, HFileBlockDefaultDecodingContext decodingCtx) throws IOException {
  if (decodingCtx.getHFileContext().isIncludesTags()) {
    int tagsLength = ByteBufferUtils.readCompressedInt(source);
    // Put as unsigned short
    dest.put((byte) ((tagsLength >> 8) & 0xff));
    dest.put((byte) (tagsLength & 0xff));
    if (tagsLength > 0) {
      TagCompressionContext tagCompressionContext = decodingCtx.getTagCompressionContext();
      // When tag compression is been used in this file, tagCompressionContext will have a not
      // null value passed.
      if (tagCompressionContext != null) {
        tagCompressionContext.uncompressTags(source, dest, tagsLength);
      } else {
        ByteBufferUtils.copyFromStreamToBuffer(dest, source, tagsLength);
      }
    }
  }
  if (decodingCtx.getHFileContext().isIncludesMvcc()) {
    long memstoreTS = -1;
    try {
      // Copy memstore timestamp from the data input stream to the byte
      // buffer.
      memstoreTS = WritableUtils.readVLong(source);
      ByteBufferUtils.writeVLong(dest, memstoreTS);
    } catch (IOException ex) {
      throw new RuntimeException("Unable to copy memstore timestamp " +
          memstoreTS + " after decoding a key/value");
    }
  }
}
 

import org.apache.hadoop.hbase.util.ByteBufferUtils; //导入方法依赖的package包/类
private int decodeKeyValue(DataInputStream source, ByteBuffer buffer,
    int prevKeyOffset)
        throws IOException, EncoderBufferTooSmallException {
  int keyLength = ByteBufferUtils.readCompressedInt(source);
  int valueLength = ByteBufferUtils.readCompressedInt(source);
  int commonLength = ByteBufferUtils.readCompressedInt(source);
  int keyOffset;
  keyLength += commonLength;

  ensureSpace(buffer, keyLength + valueLength + KeyValue.ROW_OFFSET);

  buffer.putInt(keyLength);
  buffer.putInt(valueLength);

  // copy the prefix
  if (commonLength > 0) {
    keyOffset = buffer.position();
    ByteBufferUtils.copyFromBufferToBuffer(buffer, buffer, prevKeyOffset,
        commonLength);
  } else {
    keyOffset = buffer.position();
  }

  // copy rest of the key and value
  int len = keyLength - commonLength + valueLength;
  ByteBufferUtils.copyFromStreamToBuffer(buffer, source, len);
  return keyOffset;
}
 

import org.apache.hadoop.hbase.util.ByteBufferUtils; //导入方法依赖的package包/类
@Override
public ByteBuffer uncompressKeyValues(DataInputStream source,
    int preserveHeaderLength, int skipLastBytes, boolean includesMemstoreTS)
    throws IOException {
  int decompressedSize = source.readInt();
  ByteBuffer buffer = ByteBuffer.allocate(decompressedSize +
      preserveHeaderLength);
  buffer.position(preserveHeaderLength);
  ByteBufferUtils.copyFromStreamToBuffer(buffer, source, decompressedSize);

  return buffer;
}
 

import org.apache.hadoop.hbase.util.ByteBufferUtils; //导入方法依赖的package包/类
private int uncompressKeyValue(DataInputStream source, ByteBuffer buffer,
    int prevKeyOffset)
        throws IOException, EncoderBufferTooSmallException {
  int keyLength = ByteBufferUtils.readCompressedInt(source);
  int valueLength = ByteBufferUtils.readCompressedInt(source);
  int commonLength = ByteBufferUtils.readCompressedInt(source);
  int keyOffset;
  keyLength += commonLength;

  ByteBufferUtils.ensureSpace(buffer, keyLength + valueLength
      + KeyValue.ROW_OFFSET);

  buffer.putInt(keyLength);
  buffer.putInt(valueLength);

  // copy the prefix
  if (commonLength > 0) {
    keyOffset = buffer.position();
    ByteBufferUtils.copyFromBufferToBuffer(buffer, buffer, prevKeyOffset,
        commonLength);
  } else {
    keyOffset = buffer.position();
  }

  // copy rest of the key and value
  int len = keyLength - commonLength + valueLength;
  ByteBufferUtils.copyFromStreamToBuffer(buffer, source, len);
  return keyOffset;
}
 

import org.apache.hadoop.hbase.util.ByteBufferUtils; //导入方法依赖的package包/类
protected final void afterDecodingKeyValue(DataInputStream source,
    ByteBuffer dest, HFileBlockDefaultDecodingContext decodingCtx) throws IOException {
  if (decodingCtx.getHFileContext().isIncludesTags()) {
    short tagsLength = (short) ByteBufferUtils.readCompressedInt(source);
    dest.putShort(tagsLength);
    if (tagsLength > 0) {
      TagCompressionContext tagCompressionContext = decodingCtx.getTagCompressionContext();
      // When tag compression is been used in this file, tagCompressionContext will have a not
      // null value passed.
      if (tagCompressionContext != null) {
        tagCompressionContext.uncompressTags(source, dest, tagsLength);
      } else {
        ByteBufferUtils.copyFromStreamToBuffer(dest, source, tagsLength);
      }
    }
  }
  if (decodingCtx.getHFileContext().isIncludesMvcc()) {
    long memstoreTS = -1;
    try {
      // Copy memstore timestamp from the data input stream to the byte
      // buffer.
      memstoreTS = WritableUtils.readVLong(source);
      ByteBufferUtils.writeVLong(dest, memstoreTS);
    } catch (IOException ex) {
      throw new RuntimeException("Unable to copy memstore timestamp " +
          memstoreTS + " after decoding a key/value");
    }
  }
}
 

import org.apache.hadoop.hbase.util.ByteBufferUtils; //导入方法依赖的package包/类
@Override
public ByteBuffer decodeKeyValues(DataInputStream source,
    int preserveHeaderLength, int skipLastBytes, boolean includesMemstoreTS)
    throws IOException {
  int decompressedSize = source.readInt();
  ByteBuffer buffer = ByteBuffer.allocate(decompressedSize +
      preserveHeaderLength);
  buffer.position(preserveHeaderLength);
  ByteBufferUtils.copyFromStreamToBuffer(buffer, source, decompressedSize);

  return buffer;
}