Class ByteBufUtil


  • public final class ByteBufUtil
    extends java.lang.Object
    A collection of utility methods that is related with handling ByteBuf, such as the generation of hex dump and swapping an integer's byte order.
    • Field Detail

      • MAX_CHAR_BUFFER_SIZE

        private static final int MAX_CHAR_BUFFER_SIZE
      • THREAD_LOCAL_BUFFER_SIZE

        private static final int THREAD_LOCAL_BUFFER_SIZE
      • MAX_BYTES_PER_CHAR_UTF8

        private static final int MAX_BYTES_PER_CHAR_UTF8
      • FIND_NON_ASCII

        private static final ByteProcessor FIND_NON_ASCII
        Aborts on a byte which is not a valid ASCII character.
    • Constructor Detail

      • ByteBufUtil

        private ByteBufUtil()
    • Method Detail

      • threadLocalTempArray

        static byte[] threadLocalTempArray​(int minLength)
        Allocates a new array if minLength > MAX_TL_ARRAY_LEN
      • hexDump

        public static java.lang.String hexDump​(ByteBuf buffer)
        Returns a hex dump of the specified buffer's readable bytes.
      • hexDump

        public static java.lang.String hexDump​(ByteBuf buffer,
                                               int fromIndex,
                                               int length)
        Returns a hex dump of the specified buffer's sub-region.
      • hexDump

        public static java.lang.String hexDump​(byte[] array)
        Returns a hex dump of the specified byte array.
      • hexDump

        public static java.lang.String hexDump​(byte[] array,
                                               int fromIndex,
                                               int length)
        Returns a hex dump of the specified byte array's sub-region.
      • decodeHexByte

        public static byte decodeHexByte​(java.lang.CharSequence s,
                                         int pos)
        Decode a 2-digit hex byte from within a string.
      • decodeHexDump

        public static byte[] decodeHexDump​(java.lang.CharSequence hexDump)
        Decodes a string generated by hexDump(byte[])
      • decodeHexDump

        public static byte[] decodeHexDump​(java.lang.CharSequence hexDump,
                                           int fromIndex,
                                           int length)
        Decodes part of a string generated by hexDump(byte[])
      • ensureWritableSuccess

        public static boolean ensureWritableSuccess​(int ensureWritableResult)
        Used to determine if the return value of ByteBuf.ensureWritable(int, boolean) means that there is adequate space and a write operation will succeed.
        Parameters:
        ensureWritableResult - The return value from ByteBuf.ensureWritable(int, boolean).
        Returns:
        true if ensureWritableResult means that there is adequate space and a write operation will succeed.
      • hashCode

        public static int hashCode​(ByteBuf buffer)
        Calculates the hash code of the specified buffer. This method is useful when implementing a new buffer type.
      • indexOf

        public static int indexOf​(ByteBuf needle,
                                  ByteBuf haystack)
        Returns the reader index of needle in haystack, or -1 if needle is not in haystack.
      • equals

        public static boolean equals​(ByteBuf a,
                                     int aStartIndex,
                                     ByteBuf b,
                                     int bStartIndex,
                                     int length)
        Returns true if and only if the two specified buffers are identical to each other for length bytes starting at aStartIndex index for the a buffer and bStartIndex index for the b buffer. A more compact way to express this is:

        a[aStartIndex : aStartIndex + length] == b[bStartIndex : bStartIndex + length]

      • equals

        public static boolean equals​(ByteBuf bufferA,
                                     ByteBuf bufferB)
        Returns true if and only if the two specified buffers are identical to each other as described in ByteBuf.equals(Object). This method is useful when implementing a new buffer type.
      • compare

        public static int compare​(ByteBuf bufferA,
                                  ByteBuf bufferB)
        Compares the two specified buffers as described in ByteBuf.compareTo(ByteBuf). This method is useful when implementing a new buffer type.
      • compareUintBigEndian

        private static long compareUintBigEndian​(ByteBuf bufferA,
                                                 ByteBuf bufferB,
                                                 int aIndex,
                                                 int bIndex,
                                                 int uintCountIncrement)
      • compareUintLittleEndian

        private static long compareUintLittleEndian​(ByteBuf bufferA,
                                                    ByteBuf bufferB,
                                                    int aIndex,
                                                    int bIndex,
                                                    int uintCountIncrement)
      • compareUintBigEndianA

        private static long compareUintBigEndianA​(ByteBuf bufferA,
                                                  ByteBuf bufferB,
                                                  int aIndex,
                                                  int bIndex,
                                                  int uintCountIncrement)
      • compareUintBigEndianB

        private static long compareUintBigEndianB​(ByteBuf bufferA,
                                                  ByteBuf bufferB,
                                                  int aIndex,
                                                  int bIndex,
                                                  int uintCountIncrement)
      • indexOf

        public static int indexOf​(ByteBuf buffer,
                                  int fromIndex,
                                  int toIndex,
                                  byte value)
        The default implementation of ByteBuf.indexOf(int, int, byte). This method is useful when implementing a new buffer type.
      • swapShort

        public static short swapShort​(short value)
        Toggles the endianness of the specified 16-bit short integer.
      • swapMedium

        public static int swapMedium​(int value)
        Toggles the endianness of the specified 24-bit medium integer.
      • swapInt

        public static int swapInt​(int value)
        Toggles the endianness of the specified 32-bit integer.
      • swapLong

        public static long swapLong​(long value)
        Toggles the endianness of the specified 64-bit long integer.
      • writeShortBE

        public static ByteBuf writeShortBE​(ByteBuf buf,
                                           int shortValue)
        Writes a big-endian 16-bit short integer to the buffer.
      • setShortBE

        public static ByteBuf setShortBE​(ByteBuf buf,
                                         int index,
                                         int shortValue)
        Sets a big-endian 16-bit short integer to the buffer.
      • writeMediumBE

        public static ByteBuf writeMediumBE​(ByteBuf buf,
                                            int mediumValue)
        Writes a big-endian 24-bit medium integer to the buffer.
      • firstIndexOf

        private static int firstIndexOf​(ByteBuf buffer,
                                        int fromIndex,
                                        int toIndex,
                                        byte value)
      • lastIndexOf

        private static int lastIndexOf​(ByteBuf buffer,
                                       int fromIndex,
                                       int toIndex,
                                       byte value)
      • checkCharSequenceBounds

        private static java.lang.CharSequence checkCharSequenceBounds​(java.lang.CharSequence seq,
                                                                      int start,
                                                                      int end)
      • writeUtf8

        public static ByteBuf writeUtf8​(ByteBufAllocator alloc,
                                        java.lang.CharSequence seq)
        Encode a CharSequence in UTF-8 and write it to a ByteBuf allocated with alloc.
        Parameters:
        alloc - The allocator used to allocate a new ByteBuf.
        seq - The characters to write into a buffer.
        Returns:
        The ByteBuf which contains the UTF-8 encoded result.
      • reserveAndWriteUtf8

        public static int reserveAndWriteUtf8​(ByteBuf buf,
                                              java.lang.CharSequence seq,
                                              int reserveBytes)
        Encode a CharSequence in UTF-8 and write it into reserveBytes of a ByteBuf.

        The reserveBytes must be computed (ie eagerly using utf8MaxBytes(CharSequence) or exactly with utf8Bytes(CharSequence)) to ensure this method to not fail: for performance reasons the index checks will be performed using just reserveBytes.
        This method returns the actual number of bytes written.

      • reserveAndWriteUtf8Seq

        private static int reserveAndWriteUtf8Seq​(ByteBuf buf,
                                                  java.lang.CharSequence seq,
                                                  int start,
                                                  int end,
                                                  int reserveBytes)
      • writeUtf8

        static int writeUtf8​(AbstractByteBuf buffer,
                             int writerIndex,
                             java.lang.CharSequence seq,
                             int len)
      • writeUtf8

        static int writeUtf8​(AbstractByteBuf buffer,
                             int writerIndex,
                             java.lang.CharSequence seq,
                             int start,
                             int end)
      • writeUtf8Surrogate

        private static int writeUtf8Surrogate​(AbstractByteBuf buffer,
                                              int writerIndex,
                                              char c,
                                              char c2)
      • utf8MaxBytes

        public static int utf8MaxBytes​(int seqLength)
        Returns max bytes length of UTF8 character sequence of the given length.
      • utf8MaxBytes

        public static int utf8MaxBytes​(java.lang.CharSequence seq)
        Returns max bytes length of UTF8 character sequence.

        It behaves like utf8MaxBytes(int) applied to seq CharSequence.length().

      • utf8Bytes

        public static int utf8Bytes​(java.lang.CharSequence seq)
        Returns the exact bytes length of UTF8 character sequence.

        This method is producing the exact length according to writeUtf8(ByteBuf, CharSequence).

      • utf8ByteCount

        private static int utf8ByteCount​(java.lang.CharSequence seq,
                                         int start,
                                         int end)
      • utf8BytesNonAscii

        private static int utf8BytesNonAscii​(java.lang.CharSequence seq,
                                             int start,
                                             int end)
      • writeAscii

        public static ByteBuf writeAscii​(ByteBufAllocator alloc,
                                         java.lang.CharSequence seq)
        Encode a CharSequence in ASCII and write it to a ByteBuf allocated with alloc.
        Parameters:
        alloc - The allocator used to allocate a new ByteBuf.
        seq - The characters to write into a buffer.
        Returns:
        The ByteBuf which contains the ASCII encoded result.
      • writeAscii

        public static int writeAscii​(ByteBuf buf,
                                     java.lang.CharSequence seq)
        Encode a CharSequence in ASCII and write it to a ByteBuf. This method returns the actual number of bytes written.
      • writeAscii

        static int writeAscii​(AbstractByteBuf buffer,
                              int writerIndex,
                              java.lang.CharSequence seq,
                              int len)
      • encodeString

        public static ByteBuf encodeString​(ByteBufAllocator alloc,
                                           java.nio.CharBuffer src,
                                           java.nio.charset.Charset charset)
        Encode the given CharBuffer using the given Charset into a new ByteBuf which is allocated via the ByteBufAllocator.
      • encodeString

        public static ByteBuf encodeString​(ByteBufAllocator alloc,
                                           java.nio.CharBuffer src,
                                           java.nio.charset.Charset charset,
                                           int extraCapacity)
        Encode the given CharBuffer using the given Charset into a new ByteBuf which is allocated via the ByteBufAllocator.
        Parameters:
        alloc - The ByteBufAllocator to allocate ByteBuf.
        src - The CharBuffer to encode.
        charset - The specified Charset.
        extraCapacity - the extra capacity to alloc except the space for decoding.
      • encodeString0

        static ByteBuf encodeString0​(ByteBufAllocator alloc,
                                     boolean enforceHeap,
                                     java.nio.CharBuffer src,
                                     java.nio.charset.Charset charset,
                                     int extraCapacity)
      • decodeString

        static java.lang.String decodeString​(ByteBuf src,
                                             int readerIndex,
                                             int len,
                                             java.nio.charset.Charset charset)
      • threadLocalDirectBuffer

        public static ByteBuf threadLocalDirectBuffer()
        Returns a cached thread-local direct buffer, if available.
        Returns:
        a cached thread-local direct buffer, if available. null otherwise.
      • getBytes

        public static byte[] getBytes​(ByteBuf buf,
                                      int start,
                                      int length)
        Create a copy of the underlying storage from buf into a byte array. The copy will start at start and copy length bytes.
      • getBytes

        public static byte[] getBytes​(ByteBuf buf,
                                      int start,
                                      int length,
                                      boolean copy)
        Return an array of the underlying storage from buf into a byte array. The copy will start at start and copy length bytes. If copy is true a copy will be made of the memory. If copy is false the underlying storage will be shared, if possible.
      • copy

        public static void copy​(AsciiString src,
                                int srcIdx,
                                ByteBuf dst,
                                int length)
        Copies the content of src to a ByteBuf using ByteBuf.writeBytes(byte[], int, int).
        Parameters:
        src - the source string to copy
        srcIdx - the starting offset of characters to copy
        dst - the destination buffer
        length - the number of characters to copy
      • prettyHexDump

        public static java.lang.String prettyHexDump​(ByteBuf buffer)
        Returns a multi-line hexadecimal dump of the specified ByteBuf that is easy to read by humans.
      • prettyHexDump

        public static java.lang.String prettyHexDump​(ByteBuf buffer,
                                                     int offset,
                                                     int length)
        Returns a multi-line hexadecimal dump of the specified ByteBuf that is easy to read by humans, starting at the given offset using the given length.
      • appendPrettyHexDump

        public static void appendPrettyHexDump​(java.lang.StringBuilder dump,
                                               ByteBuf buf)
        Appends the prettified multi-line hexadecimal dump of the specified ByteBuf to the specified StringBuilder that is easy to read by humans.
      • appendPrettyHexDump

        public static void appendPrettyHexDump​(java.lang.StringBuilder dump,
                                               ByteBuf buf,
                                               int offset,
                                               int length)
        Appends the prettified multi-line hexadecimal dump of the specified ByteBuf to the specified StringBuilder that is easy to read by humans, starting at the given offset using the given length.
      • isText

        public static boolean isText​(ByteBuf buf,
                                     java.nio.charset.Charset charset)
        Returns true if the given ByteBuf is valid text using the given Charset, otherwise return false.
        Parameters:
        buf - The given ByteBuf.
        charset - The specified Charset.
      • isText

        public static boolean isText​(ByteBuf buf,
                                     int index,
                                     int length,
                                     java.nio.charset.Charset charset)
        Returns true if the specified ByteBuf starting at index with length is valid text using the given Charset, otherwise return false.
        Parameters:
        buf - The given ByteBuf.
        index - The start index of the specified buffer.
        length - The length of the specified buffer.
        charset - The specified Charset.
        Throws:
        java.lang.IndexOutOfBoundsException - if index + length is greater than buf.readableBytes
      • isAscii

        private static boolean isAscii​(ByteBuf buf,
                                       int index,
                                       int length)
        Returns true if the specified ByteBuf starting at index with length is valid ASCII text, otherwise return false.
        Parameters:
        buf - The given ByteBuf.
        index - The start index of the specified buffer.
        length - The length of the specified buffer.
      • isUtf8

        private static boolean isUtf8​(ByteBuf buf,
                                      int index,
                                      int length)
        Returns true if the specified ByteBuf starting at index with length is valid UTF8 text, otherwise return false.
        Parameters:
        buf - The given ByteBuf.
        index - The start index of the specified buffer.
        length - The length of the specified buffer.
        See Also:
        UTF-8 Definition
         1. Bytes format of UTF-8
        
         The table below summarizes the format of these different octet types.
         The letter x indicates bits available for encoding bits of the character number.
        
         Char. number range  |        UTF-8 octet sequence
            (hexadecimal)    |              (binary)
         --------------------+---------------------------------------------
         0000 0000-0000 007F | 0xxxxxxx
         0000 0080-0000 07FF | 110xxxxx 10xxxxxx
         0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
         0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
         
         2. Syntax of UTF-8 Byte Sequences
        
         UTF8-octets = *( UTF8-char )
         UTF8-char   = UTF8-1 / UTF8-2 / UTF8-3 / UTF8-4
         UTF8-1      = %x00-7F
         UTF8-2      = %xC2-DF UTF8-tail
         UTF8-3      = %xE0 %xA0-BF UTF8-tail /
                       %xE1-EC 2( UTF8-tail ) /
                       %xED %x80-9F UTF8-tail /
                       %xEE-EF 2( UTF8-tail )
         UTF8-4      = %xF0 %x90-BF 2( UTF8-tail ) /
                       %xF1-F3 3( UTF8-tail ) /
                       %xF4 %x80-8F 2( UTF8-tail )
         UTF8-tail   = %x80-BF
         
      • readBytes

        static void readBytes​(ByteBufAllocator allocator,
                              java.nio.ByteBuffer buffer,
                              int position,
                              int length,
                              java.io.OutputStream out)
                       throws java.io.IOException
        Read bytes from the given ByteBuffer into the given OutputStream using the position and length. The position and limit of the given ByteBuffer may be adjusted.
        Throws:
        java.io.IOException
      • getBytes

        private static void getBytes​(java.nio.ByteBuffer inBuffer,
                                     byte[] in,
                                     int inOffset,
                                     int inLen,
                                     java.io.OutputStream out,
                                     int outLen)
                              throws java.io.IOException
        Throws:
        java.io.IOException