Package com.healthmarketscience.jackcess.impl

Class ByteUtil

  • public final class ByteUtil
extends Object
    Byte manipulation and display utilities
    Author:
    Tim McCune

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  ByteUtil.ByteStream
      Utility byte stream similar to ByteArrayOutputStream but with extended accessibility to the bytes.

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static int asUnsignedByte​(byte b)  
      static int asUnsignedShort​(short s)  
      static void clearRange​(ByteBuffer buffer, int start, int end)
      Sets all bits in the given byte range to 0.
      static void clearRemaining​(ByteBuffer buffer)
      Sets all bits in the given remaining byte range to 0.
      static void closeQuietly​(Closeable c)
      Closes the given Closeable if non-null, swallows any IOExceptions.
      static byte[] concat​(byte[] b1, byte[] b2)
      Concatenates and returns the given byte arrays.
      static void copy​(InputStream in, OutputStream out)
      Copies the given InputStream to the given OutputStream.
      static byte[] copyOf​(byte[] arr, int newLength)
      Returns a copy of the given array of the given length.
      static byte[] copyOf​(byte[] arr, int offset, int newLength)
      Returns a copy of the given array of the given length starting at the given position.
      static byte[] copyOf​(byte[] arr, int offset, int newLength, int dstOffset)
      Returns a copy of the given array of the given length starting at the given position.
      static void fillRange​(ByteBuffer buffer, int start, int end)
      Sets all bits in the given byte range to 1.
      static int findRange​(ByteBuffer buffer, int start, byte[] pattern)
      Searches for a pattern of bytes in the given buffer starting at the given offset.
      static int forward​(ByteBuffer buffer, int count)
      Moves the position of the given buffer the given count from the current position.
      static int get3ByteInt​(ByteBuffer buffer)
      Read a 3 byte int from a buffer
      static int get3ByteInt​(ByteBuffer buffer, int offset)
      Read a 3 byte int from a buffer
      static int get3ByteInt​(ByteBuffer buffer, int offset, ByteOrder order)
      Read a 3 byte int from a buffer
      static int get3ByteInt​(ByteBuffer buffer, ByteOrder order)
      Read a 3 byte int from a buffer
      static byte[] getBytes​(ByteBuffer buffer, int len)
      Reads an array of bytes from the given buffer
      static byte[] getBytes​(ByteBuffer buffer, int offset, int len)
      Reads an array of bytes from the given buffer at the given offset
      static int getInt​(ByteBuffer buffer, int offset, ByteOrder order)  
      static int getInt​(ByteBuffer buffer, ByteOrder order)  
      static int getUnsignedByte​(ByteBuffer buffer)
      Read an unsigned byte from a buffer
      static int getUnsignedByte​(ByteBuffer buffer, int offset)
      Read an unsigned byte from a buffer
      static int getUnsignedShort​(ByteBuffer buffer)
      Read an unsigned short from a buffer
      static int getUnsignedShort​(ByteBuffer buffer, int offset)
      Read an unsigned short from a buffer
      static int getUnsignedVarInt​(ByteBuffer buffer, int numBytes)
      Read an unsigned variable length int from a buffer
      static int getUnsignedVarInt​(ByteBuffer buffer, int offset, int numBytes)
      Read an unsigned variable length int from a buffer
      static void insertEmptyData​(ByteBuffer buffer, int len)
      Inserts empty data of the given length at the current position of the given buffer (moving existing data forward the given length).
      static boolean matchesRange​(ByteBuffer buffer, int start, byte[] pattern)
      Matches a pattern of bytes against the given buffer starting at the given offset.
      static void put3ByteInt​(ByteBuffer buffer, int val)
      Put an integer into the given buffer at the given offset as a 3-byte integer.
      static void put3ByteInt​(ByteBuffer buffer, int val, int offset, ByteOrder order)
      Put an integer into the given buffer at the given offset as a 3-byte integer.
      static void put3ByteInt​(ByteBuffer buffer, int val, ByteOrder order)
      Put an integer into the given buffer at the given offset as a 3-byte integer.
      static void putInt​(ByteBuffer buffer, int val, int offset, ByteOrder order)
      Writes an int at the given position in the given buffer, using the given ByteOrder
      static void putInt​(ByteBuffer buffer, int val, ByteOrder order)
      Writes an int at the current position in the given buffer, using the given ByteOrder
      static void putRange​(ByteBuffer buffer, int start, int end, byte b)
      Sets all bytes in the given byte range to the given byte value.
      static void skipFully​(DataInputStream din, int len)
      Skips the given number of bytes in the given stream
      static void swap2Bytes​(byte[] bytes, int offset)
      Swaps the 2 bytes (changes endianness) of the bytes at the given offset.
      static void swap4Bytes​(byte[] bytes, int offset)
      Swaps the 4 bytes (changes endianness) of the bytes at the given offset.
      static void swap8Bytes​(byte[] bytes, int offset)
      Swaps the 8 bytes (changes endianness) of the bytes at the given offset.
      static void toHexFile​(String fileName, ByteBuffer buffer, int offset, int size)
      Writes a chunk of data to a file in pretty printed hexidecimal.
      static String toHexString​(byte[] array)
      Convert a byte array to a hexadecimal string for display
      static String toHexString​(DatabaseImpl db, int pageNumber, int size)
      Convert the given number of bytes from the given database page to a hexidecimal string for display.
      static String toHexString​(ByteBuffer buffer, int size)
      Convert a byte buffer to a hexadecimal string for display
      static String toHexString​(ByteBuffer buffer, int offset, int size)
      Convert a byte buffer to a hexadecimal string for display
      static String toHexString​(ByteBuffer buffer, int offset, int size, boolean formatted)
      Convert a byte buffer to a hexadecimal string for display
      static void writeHexString​(ByteBuffer buffer, String hexStr)
      Writes a sequence of hexidecimal values into the given buffer, where every two characters represent one byte value.

    • Method Detail

      • put3ByteInt

        public static void put3ByteInt​(ByteBuffer buffer,
                               int val)
        Put an integer into the given buffer at the given offset as a 3-byte integer.
        Parameters:
        buffer - buffer into which to insert the int
        val - Int to convert

      • put3ByteInt

        public static void put3ByteInt​(ByteBuffer buffer,
                               int val,
                               ByteOrder order)
        Put an integer into the given buffer at the given offset as a 3-byte integer.
        Parameters:
        buffer - buffer into which to insert the int
        val - Int to convert
        order - the order to insert the bytes of the int

      • put3ByteInt

        public static void put3ByteInt​(ByteBuffer buffer,
                               int val,
                               int offset,
                               ByteOrder order)
        Put an integer into the given buffer at the given offset as a 3-byte integer.
        Parameters:
        buffer - buffer into which to insert the int
        val - Int to convert
        offset - offset at which to insert the int
        order - the order to insert the bytes of the int

      • get3ByteInt

        public static int get3ByteInt​(ByteBuffer buffer)
        Read a 3 byte int from a buffer
        Parameters:
        buffer - Buffer containing the bytes
        Returns:
        The int

      • get3ByteInt

        public static int get3ByteInt​(ByteBuffer buffer,
                              ByteOrder order)
        Read a 3 byte int from a buffer
        Parameters:
        buffer - Buffer containing the bytes
        order - the order of the bytes of the int
        Returns:
        The int

      • get3ByteInt

        public static int get3ByteInt​(ByteBuffer buffer,
                              int offset)
        Read a 3 byte int from a buffer
        Parameters:
        buffer - Buffer containing the bytes
        offset - Offset at which to start reading the int
        Returns:
        The int

      • get3ByteInt

        public static int get3ByteInt​(ByteBuffer buffer,
                              int offset,
                              ByteOrder order)
        Read a 3 byte int from a buffer
        Parameters:
        buffer - Buffer containing the bytes
        offset - Offset at which to start reading the int
        order - the order of the bytes of the int
        Returns:
        The int

      • getUnsignedByte

        public static int getUnsignedByte​(ByteBuffer buffer)
        Read an unsigned byte from a buffer
        Parameters:
        buffer - Buffer containing the bytes
        Returns:
        The unsigned byte as an int

      • getUnsignedByte

        public static int getUnsignedByte​(ByteBuffer buffer,
                                  int offset)
        Read an unsigned byte from a buffer
        Parameters:
        buffer - Buffer containing the bytes
        offset - Offset at which to read the byte
        Returns:
        The unsigned byte as an int

      • getUnsignedShort

        public static int getUnsignedShort​(ByteBuffer buffer)
        Read an unsigned short from a buffer
        Parameters:
        buffer - Buffer containing the short
        Returns:
        The unsigned short as an int

      • getUnsignedShort

        public static int getUnsignedShort​(ByteBuffer buffer,
                                   int offset)
        Read an unsigned short from a buffer
        Parameters:
        buffer - Buffer containing the short
        offset - Offset at which to read the short
        Returns:
        The unsigned short as an int

      • getInt

        public static int getInt​(ByteBuffer buffer,
                         ByteOrder order)
        Parameters:
        buffer - Buffer containing the bytes
        order - the order of the bytes of the int
        Returns:
        an int from the current position in the given buffer, read using the given ByteOrder

      • getInt

        public static int getInt​(ByteBuffer buffer,
                         int offset,
                         ByteOrder order)
        Parameters:
        buffer - Buffer containing the bytes
        offset - Offset at which to start reading the int
        order - the order of the bytes of the int
        Returns:
        an int from the given position in the given buffer, read using the given ByteOrder

      • putInt

        public static void putInt​(ByteBuffer buffer,
                          int val,
                          ByteOrder order)
        Writes an int at the current position in the given buffer, using the given ByteOrder
        Parameters:
        buffer - buffer into which to insert the int
        val - Int to insert
        order - the order to insert the bytes of the int

      • putInt

        public static void putInt​(ByteBuffer buffer,
                          int val,
                          int offset,
                          ByteOrder order)
        Writes an int at the given position in the given buffer, using the given ByteOrder
        Parameters:
        buffer - buffer into which to insert the int
        val - Int to insert
        offset - offset at which to insert the int
        order - the order to insert the bytes of the int

      • getUnsignedVarInt

        public static int getUnsignedVarInt​(ByteBuffer buffer,
                                    int numBytes)
        Read an unsigned variable length int from a buffer
        Parameters:
        buffer - Buffer containing the variable length int
        Returns:
        The unsigned int

      • getUnsignedVarInt

        public static int getUnsignedVarInt​(ByteBuffer buffer,
                                    int offset,
                                    int numBytes)
        Read an unsigned variable length int from a buffer
        Parameters:
        buffer - Buffer containing the variable length int
        offset - Offset at which to read the value
        Returns:
        The unsigned int

      • getBytes

        public static byte[] getBytes​(ByteBuffer buffer,
                              int len)
        Reads an array of bytes from the given buffer
        Parameters:
        buffer - Buffer containing the desired bytes
        len - length of the desired bytes
        Returns:
        a new buffer with the given number of bytes from the current position in the given buffer

      • getBytes

        public static byte[] getBytes​(ByteBuffer buffer,
                              int offset,
                              int len)
        Reads an array of bytes from the given buffer at the given offset
        Parameters:
        buffer - Buffer containing the desired bytes
        offset - Offset at which to read the bytes
        len - length of the desired bytes
        Returns:
        a new buffer with the given number of bytes from the given position in the given buffer

      • concat

        public static byte[] concat​(byte[] b1,
                            byte[] b2)
        Concatenates and returns the given byte arrays.

      • clearRemaining

        public static void clearRemaining​(ByteBuffer buffer)
        Sets all bits in the given remaining byte range to 0.

      • clearRange

        public static void clearRange​(ByteBuffer buffer,
                              int start,
                              int end)
        Sets all bits in the given byte range to 0.

      • fillRange

        public static void fillRange​(ByteBuffer buffer,
                             int start,
                             int end)
        Sets all bits in the given byte range to 1.

      • putRange

        public static void putRange​(ByteBuffer buffer,
                            int start,
                            int end,
                            byte b)
        Sets all bytes in the given byte range to the given byte value.

      • matchesRange

        public static boolean matchesRange​(ByteBuffer buffer,
                                   int start,
                                   byte[] pattern)
        Matches a pattern of bytes against the given buffer starting at the given offset.

      • findRange

        public static int findRange​(ByteBuffer buffer,
                            int start,
                            byte[] pattern)
        Searches for a pattern of bytes in the given buffer starting at the given offset.
        Returns:
        the offset of the pattern if a match is found, -1 otherwise

      • insertEmptyData

        public static void insertEmptyData​(ByteBuffer buffer,
                                   int len)
        Inserts empty data of the given length at the current position of the given buffer (moving existing data forward the given length). The limit of the buffer is adjusted by the given length. The buffer is expecting to have the required capacity available.

      • toHexString

        public static String toHexString​(ByteBuffer buffer,
                                 int size)
        Convert a byte buffer to a hexadecimal string for display
        Parameters:
        buffer - Buffer to display, starting at offset 0
        size - Number of bytes to read from the buffer
        Returns:
        The display String

      • toHexString

        public static String toHexString​(byte[] array)
        Convert a byte array to a hexadecimal string for display
        Parameters:
        array - byte array to display, starting at offset 0
        Returns:
        The display String

      • toHexString

        public static String toHexString​(ByteBuffer buffer,
                                 int offset,
                                 int size)
        Convert a byte buffer to a hexadecimal string for display
        Parameters:
        buffer - Buffer to display, starting at offset 0
        offset - Offset at which to start reading the buffer
        size - Number of bytes to read from the buffer
        Returns:
        The display String

      • toHexString

        public static String toHexString​(ByteBuffer buffer,
                                 int offset,
                                 int size,
                                 boolean formatted)
        Convert a byte buffer to a hexadecimal string for display
        Parameters:
        buffer - Buffer to display, starting at offset 0
        offset - Offset at which to start reading the buffer
        size - Number of bytes to read from the buffer
        formatted - flag indicating if formatting is required
        Returns:
        The display String

      • toHexString

        public static String toHexString​(DatabaseImpl db,
                                 int pageNumber,
                                 int size)
                          throws IOException
        Convert the given number of bytes from the given database page to a hexidecimal string for display.
        Throws:
        IOException

      • writeHexString

        public static void writeHexString​(ByteBuffer buffer,
                                  String hexStr)
                           throws IOException
        Writes a sequence of hexidecimal values into the given buffer, where every two characters represent one byte value.
        Throws:
        IOException

      • toHexFile

        public static void toHexFile​(String fileName,
                             ByteBuffer buffer,
                             int offset,
                             int size)
                      throws IOException
        Writes a chunk of data to a file in pretty printed hexidecimal.
        Throws:
        IOException

      • asUnsignedByte

        public static int asUnsignedByte​(byte b)
        Returns:
        the byte value converted to an unsigned int value

      • asUnsignedShort

        public static int asUnsignedShort​(short s)
        Returns:
        the short value converted to an unsigned int value

      • swap8Bytes

        public static void swap8Bytes​(byte[] bytes,
                              int offset)
        Swaps the 8 bytes (changes endianness) of the bytes at the given offset.
        Parameters:
        bytes - buffer containing bytes to swap
        offset - offset of the first byte of the bytes to swap

      • swap4Bytes

        public static void swap4Bytes​(byte[] bytes,
                              int offset)
        Swaps the 4 bytes (changes endianness) of the bytes at the given offset.
        Parameters:
        bytes - buffer containing bytes to swap
        offset - offset of the first byte of the bytes to swap

      • swap2Bytes

        public static void swap2Bytes​(byte[] bytes,
                              int offset)
        Swaps the 2 bytes (changes endianness) of the bytes at the given offset.
        Parameters:
        bytes - buffer containing bytes to swap
        offset - offset of the first byte of the bytes to swap

      • forward

        public static int forward​(ByteBuffer buffer,
                          int count)
        Moves the position of the given buffer the given count from the current position.
        Returns:
        the new buffer position

      • copyOf

        public static byte[] copyOf​(byte[] arr,
                            int newLength)
        Returns a copy of the given array of the given length.

      • copyOf

        public static byte[] copyOf​(byte[] arr,
                            int offset,
                            int newLength)
        Returns a copy of the given array of the given length starting at the given position.

      • copyOf

        public static byte[] copyOf​(byte[] arr,
                            int offset,
                            int newLength,
                            int dstOffset)
        Returns a copy of the given array of the given length starting at the given position.

      • closeQuietly

        public static void closeQuietly​(Closeable c)
        Closes the given Closeable if non-null, swallows any IOExceptions.