Package org.firebirdsql.gds

Class VaxEncoding

  • public final class VaxEncoding
extends java.lang.Object
    Helper methods for decoding Vax style (little endian) integers as used by Firebird from byte arrays.
    Since:
    3.0
    Author:
    Mark Rotteveel

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static void encodeVaxInteger​(java.io.OutputStream stream, int value)
      Encodes an integer using vax encoding into the output stream, length prefix is included.
      static void encodeVaxInteger2WithoutLength​(java.io.OutputStream stream, int value)
      Encodes an integer using two byte vax encoding into the output stream, without length prefix.
      static void encodeVaxIntegerWithoutLength​(java.io.OutputStream stream, int value)
      Encodes an integer using vax encoding into the output stream, without length prefix.
      static void encodeVaxLong​(java.io.OutputStream stream, long value)
      Encodes a long using vax encoding into the output stream, length prefix is included.
      static void encodeVaxLongWithoutLength​(java.io.OutputStream stream, long value)
      Encodes a long using vax encoding into the output stream, without length prefix.
      static int iscVaxInteger​(byte[] buffer, int startPosition, int length)
      Reads Vax style integers from the supplied buffer, starting at startPosition and reading for length bytes.
      static int iscVaxInteger2​(byte[] buffer, int startPosition)
      Variant of iscVaxInteger(byte[], int, int) specifically for two-byte integers.
      static long iscVaxLong​(byte[] buffer, int startPosition, int length)
      Reads Vax style integers from the supplied buffer, starting at startPosition and reading for length bytes.

      • Methods inherited from class java.lang.Object

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

    • Method Detail

      • iscVaxInteger

        public static int iscVaxInteger​(byte[] buffer,
                                int startPosition,
                                int length)
        Reads Vax style integers from the supplied buffer, starting at startPosition and reading for length bytes.

        This method is useful for lengths up to 4 bytes (ie normal Java integers (int). For larger lengths it will return 0. Use iscVaxLong(byte[], int, int) for reading values with length up to 8 bytes. For decoding 2 byte integers, use iscVaxInteger2(byte[], int) for optimal performance.

        Parameters:
        buffer - The byte array from which the integer is to be retrieved
        startPosition - The offset starting position from which to start retrieving byte values
        length - number of bytes to read
        Returns:
        The integer value retrieved from the bytes
        See Also:
        iscVaxLong(byte[], int, int), iscVaxInteger2(byte[], int)

      • encodeVaxInteger

        public static void encodeVaxInteger​(java.io.OutputStream stream,
                                    int value)
                             throws java.io.IOException
        Encodes an integer using vax encoding into the output stream, length prefix is included.
        Parameters:
        stream - Output stream to write
        value - Value to encode
        Throws:
        java.io.IOException

      • encodeVaxIntegerWithoutLength

        public static void encodeVaxIntegerWithoutLength​(java.io.OutputStream stream,
                                                 int value)
                                          throws java.io.IOException
        Encodes an integer using vax encoding into the output stream, without length prefix.
        Parameters:
        stream - Output stream to write
        value - Value to encode
        Throws:
        java.io.IOException

      • iscVaxLong

        public static long iscVaxLong​(byte[] buffer,
                              int startPosition,
                              int length)
        Reads Vax style integers from the supplied buffer, starting at startPosition and reading for length bytes.

        This method is useful for lengths up to 8 bytes (ie normal Java longs (long). For larger lengths it will return 0.

        Parameters:
        buffer - The byte array from which the integer is to be retrieved
        startPosition - The offset starting position from which to start retrieving byte values
        length - number of bytes to read
        Returns:
        The integer value retrieved from the bytes
        See Also:
        iscVaxInteger(byte[], int, int), iscVaxInteger2(byte[], int)

      • encodeVaxLong

        public static void encodeVaxLong​(java.io.OutputStream stream,
                                 long value)
                          throws java.io.IOException
        Encodes a long using vax encoding into the output stream, length prefix is included.
        Parameters:
        stream - Output stream to write
        value - Value to encode
        Throws:
        java.io.IOException

      • encodeVaxLongWithoutLength

        public static void encodeVaxLongWithoutLength​(java.io.OutputStream stream,
                                              long value)
                                       throws java.io.IOException
        Encodes a long using vax encoding into the output stream, without length prefix.
        Parameters:
        stream - Output stream to write
        value - Value to encode
        Throws:
        java.io.IOException

      • iscVaxInteger2

        public static int iscVaxInteger2​(byte[] buffer,
                                 int startPosition)
        Variant of iscVaxInteger(byte[], int, int) specifically for two-byte integers.
        Parameters:
        buffer - The byte array from which the integer is to be retrieved
        startPosition - The offset starting position from which to start retrieving byte values
        Returns:
        The integer value retrieved from the bytes
        See Also:
        iscVaxInteger(byte[], int, int), iscVaxLong(byte[], int, int)

      • encodeVaxInteger2WithoutLength

        public static void encodeVaxInteger2WithoutLength​(java.io.OutputStream stream,
                                                  int value)
                                           throws java.io.IOException
        Encodes an integer using two byte vax encoding into the output stream, without length prefix.
        Parameters:
        stream - Output stream to write
        value - Value to encode
        Throws:
        java.io.IOException