Package org.graylog2.inputs.transports.netty

Class LenientDelimiterBasedFrameDecoder

java.lang.Object
io.netty.channel.ChannelHandlerAdapter
io.netty.channel.ChannelInboundHandlerAdapter
io.netty.handler.codec.ByteToMessageDecoder
org.graylog2.inputs.transports.netty.LenientDelimiterBasedFrameDecoder
All Implemented Interfaces:
io.netty.channel.ChannelHandler, io.netty.channel.ChannelInboundHandler
public class LenientDelimiterBasedFrameDecoder extends io.netty.handler.codec.ByteToMessageDecoder
A decoder that splits the received ByteBufs by one or more delimiters. It is particularly useful for decoding the frames which ends with a delimiter such as NUL or newline characters.

Predefined delimiters

Delimiters defines frequently used delimiters for convenience' sake.

Specifying more than one delimiter

LenientDelimiterBasedFrameDecoder allows you to specify more than one delimiter. If more than one delimiter is found in the buffer, it chooses the delimiter which produces the shortest frame. For example, if you have the following data in the buffer: 

 +--------------+
 | ABC\nDEF\r\n |
 +--------------+
a LenientDelimiterBasedFrameDecoder(Delimiters.lineDelimiter()) will choose '\n' as the first delimiter and produce two frames: 
 +-----+-----+
 | ABC | DEF |
 +-----+-----+
rather than incorrectly choosing '\r\n' as the first delimiter: 
 +----------+
 | ABC\nDEF |
 +----------+

  • Nested Class Summary

    Nested classes/interfaces inherited from class io.netty.handler.codec.ByteToMessageDecoder

    io.netty.handler.codec.ByteToMessageDecoder.Cumulator

    Nested classes/interfaces inherited from interface io.netty.channel.ChannelHandler

    io.netty.channel.ChannelHandler.Sharable

  • Field Summary

    Fields inherited from class io.netty.handler.codec.ByteToMessageDecoder

    COMPOSITE_CUMULATOR, MERGE_CUMULATOR

  • Constructor Summary

    Constructors
    Constructor
    Description
    LenientDelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, boolean failFast, boolean emitLastLineWithoutDelimiter, io.netty.buffer.ByteBuf... delimiters)
    Creates a new instance.
    LenientDelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, boolean failFast, io.netty.buffer.ByteBuf delimiter)
    Creates a new instance.
    LenientDelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, io.netty.buffer.ByteBuf delimiter)
    Creates a new instance.
    LenientDelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, io.netty.buffer.ByteBuf... delimiters)
    Creates a new instance.
    LenientDelimiterBasedFrameDecoder(int maxFrameLength, io.netty.buffer.ByteBuf delimiter)
    Creates a new instance.
    LenientDelimiterBasedFrameDecoder(int maxFrameLength, io.netty.buffer.ByteBuf... delimiters)
    Creates a new instance.

  • Method Summary

    Modifier and Type
    Method
    Description
    protected Object
    decode(io.netty.channel.ChannelHandlerContext ctx, io.netty.buffer.ByteBuf buffer)
    Create a frame out of the ByteBuf and return it.
    protected final void
    decode(io.netty.channel.ChannelHandlerContext ctx, io.netty.buffer.ByteBuf in, List<Object> out)
     

    Methods inherited from class io.netty.handler.codec.ByteToMessageDecoder

    actualReadableBytes, callDecode, channelInactive, channelRead, channelReadComplete, decodeLast, discardSomeReadBytes, handlerRemoved, handlerRemoved0, internalBuffer, isSingleDecode, setCumulator, setDiscardAfterReads, setSingleDecode, userEventTriggered

    Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

    channelActive, channelRegistered, channelUnregistered, channelWritabilityChanged, exceptionCaught

    Methods inherited from class io.netty.channel.ChannelHandlerAdapter

    ensureNotSharable, handlerAdded, isSharable

    Methods inherited from class java.lang.Object

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

    Methods inherited from interface io.netty.channel.ChannelHandler

    handlerAdded

  • Constructor Details

    • LenientDelimiterBasedFrameDecoder

      public LenientDelimiterBasedFrameDecoder(int maxFrameLength, io.netty.buffer.ByteBuf delimiter)
      Creates a new instance.
      Parameters:
      maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.
      delimiter - the delimiter

    • LenientDelimiterBasedFrameDecoder

      public LenientDelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, io.netty.buffer.ByteBuf delimiter)
      Creates a new instance.
      Parameters:
      maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.
      stripDelimiter - whether the decoded frame should strip out the delimiter or not
      delimiter - the delimiter

    • LenientDelimiterBasedFrameDecoder

      public LenientDelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, boolean failFast, io.netty.buffer.ByteBuf delimiter)
      Creates a new instance.
      Parameters:
      maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.
      stripDelimiter - whether the decoded frame should strip out the delimiter or not
      failFast - If true, a TooLongFrameException is thrown as soon as the decoder notices the length of the frame will exceed maxFrameLength regardless of whether the entire frame has been read. If false, a TooLongFrameException is thrown after the entire frame that exceeds maxFrameLength has been read.
      delimiter - the delimiter

    • LenientDelimiterBasedFrameDecoder

      public LenientDelimiterBasedFrameDecoder(int maxFrameLength, io.netty.buffer.ByteBuf... delimiters)
      Creates a new instance.
      Parameters:
      maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.
      delimiters - the delimiters

    • LenientDelimiterBasedFrameDecoder

      public LenientDelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, io.netty.buffer.ByteBuf... delimiters)
      Creates a new instance.
      Parameters:
      maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.
      stripDelimiter - whether the decoded frame should strip out the delimiter or not
      delimiters - the delimiters

    • LenientDelimiterBasedFrameDecoder

      public LenientDelimiterBasedFrameDecoder(int maxFrameLength, boolean stripDelimiter, boolean failFast, boolean emitLastLineWithoutDelimiter, io.netty.buffer.ByteBuf... delimiters)
      Creates a new instance.
      Parameters:
      maxFrameLength - the maximum length of the decoded frame. A TooLongFrameException is thrown if the length of the frame exceeds this value.
      stripDelimiter - whether the decoded frame should strip out the delimiter or not
      failFast - If true, a TooLongFrameException is thrown as soon as the decoder notices the length of the frame will exceed maxFrameLength regardless of whether the entire frame has been read. If false, a TooLongFrameException is thrown after the entire frame that exceeds maxFrameLength has been read.
      emitLastLineWithoutDelimiter - emit the last line even if it doesn't end with the delimiter
      delimiters - the delimiters

  • Method Details

    • decode

      protected final void decode(io.netty.channel.ChannelHandlerContext ctx, io.netty.buffer.ByteBuf in, List<Object> out) throws Exception
      Specified by:
      decode in class io.netty.handler.codec.ByteToMessageDecoder
      Throws:
      Exception

    • decode

      protected Object decode(io.netty.channel.ChannelHandlerContext ctx, io.netty.buffer.ByteBuf buffer) throws Exception
      Create a frame out of the ByteBuf and return it.
      Parameters:
      ctx - the ChannelHandlerContext which this ByteToMessageDecoder belongs to
      buffer - the ByteBuf from which to read data
      Returns:
      frame the ByteBuf which represent the frame or null if no frame could be created.
      Throws:
      Exception