Package org.roaringbitmap.bsi

Class WritableUtils

  • public class WritableUtils
extends java.lang.Object
    WritableUtils

    copy from org.apache.hadoop.io.WritableUtils

    • Constructor Summary

      Constructors 
      Constructor Description
      WritableUtils()  

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static int decodeVIntSize​(byte value)
      Parse the first byte of a vint/vlong to determine the number of bytes
      static boolean isNegativeVInt​(byte value)
      Given the first byte of a vint/vlong, determine the sign
      static int readVInt​(java.io.DataInput stream)
      Reads a zero-compressed encoded integer from input stream and returns it.
      static long readVLong​(java.io.DataInput stream)
      Reads a zero-compressed encoded long from input stream and returns it.
      static void writeVInt​(java.io.DataOutput stream, int i)
      Serializes an integer to a binary stream with zero-compressed encoding.
      static void writeVLong​(java.io.DataOutput stream, long i)
      Serializes a long to a binary stream with zero-compressed encoding.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • WritableUtils

        public WritableUtils()

    • Method Detail

      • writeVInt

        public static void writeVInt​(java.io.DataOutput stream,
                             int i)
                      throws java.io.IOException
        Serializes an integer to a binary stream with zero-compressed encoding. For -120 <= i <= 127, only one byte is used with the actual value. For other values of i, the first byte value indicates whether the integer is positive or negative, and the number of bytes that follow. If the first byte value v is between -121 and -124, the following integer is positive, with number of bytes that follow are -(v+120). If the first byte value v is between -125 and -128, the following integer is negative, with number of bytes that follow are -(v+124). Bytes are stored in the high-non-zero-byte-first order.
        Parameters:
        stream - Binary output stream
        i - Integer to be serialized
        Throws:
        java.io.IOException

      • writeVLong

        public static void writeVLong​(java.io.DataOutput stream,
                              long i)
                       throws java.io.IOException
        Serializes a long to a binary stream with zero-compressed encoding. For -112 <= i <= 127, only one byte is used with the actual value. For other values of i, the first byte value indicates whether the long is positive or negative, and the number of bytes that follow. If the first byte value v is between -113 and -120, the following long is positive, with number of bytes that follow are -(v+112). If the first byte value v is between -121 and -128, the following long is negative, with number of bytes that follow are -(v+120). Bytes are stored in the high-non-zero-byte-first order.
        Parameters:
        stream - Binary output stream
        i - Long to be serialized
        Throws:
        java.io.IOException

      • readVLong

        public static long readVLong​(java.io.DataInput stream)
                      throws java.io.IOException
        Reads a zero-compressed encoded long from input stream and returns it.
        Parameters:
        stream - Binary input stream
        Returns:
        deserialized long from stream.
        Throws:
        java.io.IOException

      • readVInt

        public static int readVInt​(java.io.DataInput stream)
                    throws java.io.IOException
        Reads a zero-compressed encoded integer from input stream and returns it.
        Parameters:
        stream - Binary input stream
        Returns:
        deserialized integer from stream.
        Throws:
        java.io.IOException

      • isNegativeVInt

        public static boolean isNegativeVInt​(byte value)
        Given the first byte of a vint/vlong, determine the sign
        Parameters:
        value - the first byte
        Returns:
        is the value negative

      • decodeVIntSize

        public static int decodeVIntSize​(byte value)
        Parse the first byte of a vint/vlong to determine the number of bytes
        Parameters:
        value - the first byte of the vint/vlong
        Returns:
        the total number of bytes (1 to 9)