Package com.wowza.util

Class BufferUtils

  • public class BufferUtils
extends Object

    BufferUtils: utilities for converting between binary data and Java primitive types. Faster than Java runtime equivalents

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static String[] alphas  
      static String[] hexadecimal  

    • Constructor Summary

      Constructors 
      Constructor Description
      BufferUtils()  

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static int byteArrayToInt​(byte[] b)
      Convert byte array to int
      static int byteArrayToInt​(byte[] b, int offset)
      Conver byte array to int with offset
      static int byteArrayToInt​(byte[] b, int offset, int count)
      Convert byte array to int with offset.
      static int byteArrayToInt​(byte[] b, int offset, int count, boolean isReverse)
      Convert byte array to int with offset.
      static long byteArrayToLong​(byte[] b)
      Convert byte array to long
      static long byteArrayToLong​(byte[] b, int offset)
      Conver byte array to long with offset
      static long byteArrayToLong​(byte[] b, int offset, int count)
      Convert byte array to long with offset.
      static long byteArrayToLong​(byte[] b, int offset, int count, boolean isReverse)
      Convert byte array to long with offset.
      static int byteArrayToShort​(byte[] b)
      Convert byte array to int
      static int byteArrayToShort​(byte[] b, int offset)
      Conver byte array to int with offset
      static int byteArrayToShort​(byte[] b, int offset, int count)
      Convert byte array to int with offset.
      static int byteArrayToShort​(byte[] b, int offset, int count, boolean isReverse)
      Convert byte array to int with offset.
      static String byteArrayToString​(byte[] b)
      Convert a byte array to a String (UTF-8 encoding assumed)
      static String byteArrayToString​(byte[] b, int offset, int count)
      Convert a byte array to a String (UTF-8 encoding assumed)
      static String byteArrayToString​(byte[] b, int offset, int count, String charsetName)
      Convert a byte array to a String
      static byte[] decodeHexString​(String hexStr)
      Decode a string as a byte array
      static int doCRC32​(int crc, byte[] buffer, int offset, int len)
      Calculate an IEEE CRC32 value for MPEG transport stream from a starting crc value
      static String encodeHexString​(byte[] bytes)
      Encode a byte array as a string
      static String encodeHexString​(byte[] bytes, int offset, int len)
      Encode a byte array as a string
      static int getUnsignedShort​(java.nio.ByteBuffer buffer)  
      static int indexOf​(byte[] source, byte[] pattern)
      Finds the first occurrence of a byte pattern in a byte buffer.
      static int indexOfDifferent​(byte[] buffer1, byte[] buffer2)
      Compare two byte buffers, and return the index of the first byte that is different.
      static byte[] intToByteArray​(int value)
      Convert a int value to a byte array in network order
      static void intToByteArray​(int value, byte[] buffer, int offset, int size)
      Convert a int value to a byte array in network order
      static void intToByteArray​(int value, byte[] buffer, int offset, int size, boolean isReverse)
      Convert a int value to a byte array in network order
      static byte[] intToByteArray​(int value, int size)
      Convert a int value to a byte array in network order
      static byte[] longToByteArray​(long value)
      Convert a long value to a byte array in network order
      static void longToByteArray​(long value, byte[] buffer, int offset, int size)
      Convert a long value to a byte array in network order
      static void longToByteArray​(long value, byte[] buffer, int offset, int size, boolean isReverse)
      Convert a long value to a byte array in network order
      static byte[] longToByteArray​(long value, int size)
      Convert a long value to a byte array in network order
      static boolean patternMatches​(byte[] source, int offset, byte... pattern)  
      static boolean startsWith​(byte[] source, byte[] pattern)  

      • Methods inherited from class java.lang.Object

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

    • Field Detail

      • hexadecimal

        public static final String[] hexadecimal

      • alphas

        public static final String[] alphas

    • Constructor Detail

      • BufferUtils

        public BufferUtils()

    • Method Detail

      • encodeHexString

        public static String encodeHexString​(byte[] bytes)
        Encode a byte array as a string
        Parameters:
        bytes - byte array
        Returns:
        string

      • encodeHexString

        public static String encodeHexString​(byte[] bytes,
                                     int offset,
                                     int len)
        Encode a byte array as a string
        Parameters:
        bytes - byte array
        offset - offset
        len - length
        Returns:
        string

      • decodeHexString

        public static byte[] decodeHexString​(String hexStr)
        Decode a string as a byte array
        Parameters:
        hexStr - string
        Returns:
        byte array

      • byteArrayToString

        public static String byteArrayToString​(byte[] b)
        Convert a byte array to a String (UTF-8 encoding assumed)
        Parameters:
        b - byte array
        Returns:
        resultant string

      • byteArrayToString

        public static String byteArrayToString​(byte[] b,
                                       int offset,
                                       int count)
        Convert a byte array to a String (UTF-8 encoding assumed)
        Parameters:
        b - byte array
        offset - offset
        count - len
        Returns:
        resultant string

      • byteArrayToString

        public static String byteArrayToString​(byte[] b,
                                       int offset,
                                       int count,
                                       String charsetName)
        Convert a byte array to a String
        Parameters:
        b - byte array
        offset - offset
        count - len
        charsetName - character set name
        Returns:
        resultant string

      • byteArrayToLong

        public static long byteArrayToLong​(byte[] b)
        Convert byte array to long
        Parameters:
        b - byte array (8 bytes)
        Returns:
        long value

      • byteArrayToLong

        public static long byteArrayToLong​(byte[] b,
                                   int offset)
        Conver byte array to long with offset
        Parameters:
        b - byte array (8 bytes)
        offset - offset
        Returns:
        long value

      • byteArrayToLong

        public static long byteArrayToLong​(byte[] b,
                                   int offset,
                                   int count)
        Convert byte array to long with offset. Count is the number of bytes. Can be less than 8. If less than 8 just fills lower bits in value.
        Parameters:
        b - byte array
        offset - offset
        count - number of bytes
        Returns:
        long value

      • byteArrayToLong

        public static long byteArrayToLong​(byte[] b,
                                   int offset,
                                   int count,
                                   boolean isReverse)
        Convert byte array to long with offset. Count is the number of bytes. Can be less than 8. If less than 8 just fills lower bits in value. The reverse flag allows data to be in reverse order.
        Parameters:
        b - byte array
        offset - offset
        count - number of bytes
        isReverse - is data in reverse order
        Returns:
        long value

      • byteArrayToInt

        public static int byteArrayToInt​(byte[] b)
        Convert byte array to int
        Parameters:
        b - byte array (4 bytes)
        Returns:
        int value

      • byteArrayToInt

        public static int byteArrayToInt​(byte[] b,
                                 int offset)
        Conver byte array to int with offset
        Parameters:
        b - byte array (4 bytes)
        offset - offset
        Returns:
        int value

      • byteArrayToInt

        public static int byteArrayToInt​(byte[] b,
                                 int offset,
                                 int count)
        Convert byte array to int with offset. Count is the number of bytes. Can be less than 4. If less than 4 just fills lower bits in value.
        Parameters:
        b - byte array
        offset - offset
        count - number of bytes
        Returns:
        int value

      • byteArrayToInt

        public static int byteArrayToInt​(byte[] b,
                                 int offset,
                                 int count,
                                 boolean isReverse)
        Convert byte array to int with offset. Count is the number of bytes. Can be less than 4. If less than 4 just fills lower bits in value. The reverse flag allows data to be in reverse order.
        Parameters:
        b - byte array
        offset - offset
        count - number of bytes
        isReverse - is data in reverse order
        Returns:
        int value

      • byteArrayToShort

        public static int byteArrayToShort​(byte[] b)
        Convert byte array to int
        Parameters:
        b - byte array (2 bytes)
        Returns:
        int value

      • byteArrayToShort

        public static int byteArrayToShort​(byte[] b,
                                   int offset)
        Conver byte array to int with offset
        Parameters:
        b - byte array (2 bytes)
        offset - offset
        Returns:
        int value

      • byteArrayToShort

        public static int byteArrayToShort​(byte[] b,
                                   int offset,
                                   int count)
        Convert byte array to int with offset. Count is the number of bytes. Can be less than 2. If less than 2 just fills lower bits in value.
        Parameters:
        b - byte array
        offset - offset
        count - number of bytes
        Returns:
        int value

      • byteArrayToShort

        public static int byteArrayToShort​(byte[] b,
                                   int offset,
                                   int count,
                                   boolean isReverse)
        Convert byte array to int with offset. Count is the number of bytes. Can be less than 2. If less than 2 just fills lower bits in value. The reverse flag allows data to be in reverse order.
        Parameters:
        b - byte array
        offset - offset
        count - number of bytes
        isReverse - is data in reverse order
        Returns:
        int value

      • intToByteArray

        public static byte[] intToByteArray​(int value)
        Convert a int value to a byte array in network order
        Parameters:
        value - value
        Returns:
        4-byte array with value

      • intToByteArray

        public static byte[] intToByteArray​(int value,
                                    int size)
        Convert a int value to a byte array in network order
        Parameters:
        value - value
        size - size of resultant byte array
        Returns:
        size-byte array with value

      • intToByteArray

        public static void intToByteArray​(int value,
                                  byte[] buffer,
                                  int offset,
                                  int size)
        Convert a int value to a byte array in network order
        Parameters:
        value - value
        buffer - destination byte array
        offset - starting offset in byte array
        size - number of bytes to write

      • intToByteArray

        public static void intToByteArray​(int value,
                                  byte[] buffer,
                                  int offset,
                                  int size,
                                  boolean isReverse)
        Convert a int value to a byte array in network order
        Parameters:
        value - value
        buffer - destination byte array
        offset - starting offset in byte array
        size - number of bytes to write
        isReverse - is data in reverse order

      • longToByteArray

        public static byte[] longToByteArray​(long value)
        Convert a long value to a byte array in network order
        Parameters:
        value - value
        Returns:
        8-byte array with value

      • longToByteArray

        public static byte[] longToByteArray​(long value,
                                     int size)
        Convert a long value to a byte array in network order
        Parameters:
        value - value
        size - size of resultant byte array
        Returns:
        size-byte array with value

      • longToByteArray

        public static void longToByteArray​(long value,
                                   byte[] buffer,
                                   int offset,
                                   int size)
        Convert a long value to a byte array in network order
        Parameters:
        value - value
        buffer - destination byte array
        offset - starting offset in byte array
        size - number of bytes to write

      • longToByteArray

        public static void longToByteArray​(long value,
                                   byte[] buffer,
                                   int offset,
                                   int size,
                                   boolean isReverse)
        Convert a long value to a byte array in network order
        Parameters:
        value - value
        buffer - destination byte array
        offset - starting offset in byte array
        size - number of bytes to write
        isReverse - is data in reverse order

      • getUnsignedShort

        public static int getUnsignedShort​(java.nio.ByteBuffer buffer)

      • doCRC32

        public static int doCRC32​(int crc,
                          byte[] buffer,
                          int offset,
                          int len)
        Calculate an IEEE CRC32 value for MPEG transport stream from a starting crc value
        Parameters:
        crc - starting crc value
        buffer - buffer
        offset - offset
        len - len
        Returns:
        crc value

      • indexOf

        public static int indexOf​(byte[] source,
                          byte[] pattern)
        Finds the first occurrence of a byte pattern in a byte buffer.

        Note: If we want to improve the performance, we could implement the Knuth-Morris-Pratt algorithm. But I don't need the speed nor do I have time today!

        Parameters:
        source - The source byte buffer
        pattern - the pattern we're looking for.
        Returns:
        the index of source where the pattern is found, else -1

      • patternMatches

        public static boolean patternMatches​(byte[] source,
                                     int offset,
                                     byte... pattern)
        Parameters:
        source - byte array, which is to be searched
        offset - offset that the pattern will be matched from
        pattern - variable number of bytes to look for from index
        Returns:
        Return true if the input pattern matches from offset in the byte array passed in. Otherwise, return false.

      • indexOfDifferent

        public static int indexOfDifferent​(byte[] buffer1,
                                   byte[] buffer2)
        Compare two byte buffers, and return the index of the first byte that is different.
        Parameters:
        buffer1 - byte array1
        buffer2 - byte array2
        Returns:
        index where buffers differ, or -1.

      • startsWith

        public static boolean startsWith​(byte[] source,
                                 byte[] pattern)