Java WritableUtils.decodeVIntSize方法代碼示例

import org.apache.hadoop.io.WritableUtils; //導入方法依賴的package包/類
/**
 * Actually do the mvcc read. Does no checks.
 * @param position
 */
private void _readMvccVersion(final int position) {
  // This is Bytes#bytesToVint inlined so can save a few instructions in this hot method; i.e.
  // previous if one-byte vint, we'd redo the vint call to find int size.
  // Also the method is kept small so can be inlined.
  byte firstByte = blockBuffer.array()[position];
  int len = WritableUtils.decodeVIntSize(firstByte);
  if (len == 1) {
    this.currMemstoreTS = firstByte;
  } else {
    long i = 0;
    for (int idx = 0; idx < len - 1; idx++) {
      byte b = blockBuffer.array()[position + 1 + idx];
      i = i << 8;
      i = i | (b & 0xFF);
    }
    currMemstoreTS = (WritableUtils.isNegativeVInt(firstByte) ? ~i : i);
  }
  this.currMemstoreTSLen = len;
}
 

import org.apache.hadoop.io.WritableUtils; //導入方法依賴的package包/類
/**
 * @param buffer buffer to convert
 * @return vint bytes as an integer.
 */
public static long bytesToVint(final byte [] buffer) {
  int offset = 0;
  byte firstByte = buffer[offset++];
  int len = WritableUtils.decodeVIntSize(firstByte);
  if (len == 1) {
    return firstByte;
  }
  long i = 0;
  for (int idx = 0; idx < len-1; idx++) {
    byte b = buffer[offset++];
    i = i << 8;
    i = i | (b & 0xFF);
  }
  return (WritableUtils.isNegativeVInt(firstByte) ? ~i : i);
}
 

import org.apache.hadoop.io.WritableUtils; //導入方法依賴的package包/類
public int compare(byte[] b1, int s1, int l1,
    byte[] b2, int s2, int l2) {
  int n1 = WritableUtils.decodeVIntSize(b1[s1]);
  int n2 = WritableUtils.decodeVIntSize(b2[s2]);
  List <KeyDescription> allKeySpecs = keyFieldHelper.keySpecs();

  if (allKeySpecs.size() == 0) {
    return compareBytes(b1, s1 + n1, l1 - n1, b2, s2 + n2, l2 - n2);
  }
  
  int []lengthIndicesFirst = 
    keyFieldHelper.getWordLengths(b1, s1 + n1, s1 + l1);
  int []lengthIndicesSecond = 
    keyFieldHelper.getWordLengths(b2, s2 + n2, s2 + l2);
  
  for (KeyDescription keySpec : allKeySpecs) {
    int startCharFirst = keyFieldHelper.getStartOffset(b1, s1 + n1, s1 + l1,
      lengthIndicesFirst, keySpec);
    int endCharFirst = keyFieldHelper.getEndOffset(b1, s1 + n1, s1 + l1, 
      lengthIndicesFirst, keySpec);
    int startCharSecond = keyFieldHelper.getStartOffset(b2, s2 + n2, s2 + l2,
      lengthIndicesSecond, keySpec);
    int endCharSecond = keyFieldHelper.getEndOffset(b2, s2 + n2, s2 + l2, 
      lengthIndicesSecond, keySpec);
    int result;
    if ((result = compareByteSequence(b1, startCharFirst, endCharFirst, b2, 
        startCharSecond, endCharSecond, keySpec)) != 0) {
      return result;
    }
  }
  return 0;
}
 

import org.apache.hadoop.io.WritableUtils; //導入方法依賴的package包/類
public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {
  int n1 = WritableUtils.decodeVIntSize(b1[s1]);
  int n2 = WritableUtils.decodeVIntSize(b2[s2]);
  n1 -= WritableUtils.getVIntSize(n1);
  n2 -= WritableUtils.getVIntSize(n2);
  return compareBytes(b1, s1+n1, l1-n1, b2, s2+n2, l2-n2);
}
 

import org.apache.hadoop.io.WritableUtils; //導入方法依賴的package包/類
/**
 * Similar to {@link WritableUtils#readVLong(DataInput)} but reads from a
 * {@link ByteBuffer}.
 */
public static long readVLong(ByteBuffer in) {
  byte firstByte = in.get();
  int len = WritableUtils.decodeVIntSize(firstByte);
  if (len == 1) {
    return firstByte;
  }
  long i = 0;
  for (int idx = 0; idx < len-1; idx++) {
    byte b = in.get();
    i = i << 8;
    i = i | (b & 0xFF);
  }
  return (WritableUtils.isNegativeVInt(firstByte) ? (i ^ -1L) : i);
}
 

import org.apache.hadoop.io.WritableUtils; //導入方法依賴的package包/類
/**
 * Reads a zero-compressed encoded long from input buffer and returns it.
 * @param buffer Binary array
 * @param offset Offset into array at which vint begins.
 * @return deserialized long from buffer.
 */
public static long readAsVLong(final byte [] buffer, final int offset) {
  byte firstByte = buffer[offset];
  int len = WritableUtils.decodeVIntSize(firstByte);
  if (len == 1) {
    return firstByte;
  }
  long i = 0;
  for (int idx = 0; idx < len-1; idx++) {
    byte b = buffer[offset + 1 + idx];
    i = i << 8;
    i = i | (b & 0xFF);
  }
  return (WritableUtils.isNegativeVInt(firstByte) ? ~i : i);
}
 

import org.apache.hadoop.io.WritableUtils; //導入方法依賴的package包/類
public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {
  int n1 = WritableUtils.decodeVIntSize(b1[s1]);
  int n2 = WritableUtils.decodeVIntSize(b2[s2]);
  return -1 * WritableComparator.compareBytes(b1, s1+n1, l1-n1,
                                              b2, s2+n2, l2-n2);
}