Package io.netty.handler.codec.protobuf

Class ProtobufVarint32LengthFieldPrepender

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelOutboundHandlerAdapter

io.netty.handler.codec.MessageToByteEncoder<ByteBuf>

io.netty.handler.codec.protobuf.ProtobufVarint32LengthFieldPrepender

All Implemented Interfaces:

ChannelHandler, ChannelOutboundHandler

@Sharable
public class ProtobufVarint32LengthFieldPrepender
extends MessageToByteEncoder<ByteBuf>

An encoder that prepends the Google Protocol Buffers Base 128 Varints integer length field. For example:

 BEFORE ENCODE (300 bytes)       AFTER ENCODE (302 bytes)
 +---------------+               +--------+---------------+
 | Protobuf Data |-------------->| Length | Protobuf Data |
 |  (300 bytes)  |               | 0xAC02 |  (300 bytes)  |
 +---------------+               +--------+---------------+
 

*

See Also:

• CodedOutputStream
• CodedOutputByteBufferNano

Nested Class Summary

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

ChannelHandler.Sharable

Constructor Summary

Constructors

Constructor	Description
ProtobufVarint32LengthFieldPrepender()

Method Summary

Modifier and Type	Method	Description
protected void	encode(ChannelHandlerContext ctx, ByteBuf msg, ByteBuf out)	Encode a message into a ByteBuf.

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

acceptOutboundMessage, allocateBuffer, isPreferDirect, write

Methods inherited from class io.netty.channel.ChannelOutboundHandlerAdapter

bind, close, connect, deregister, disconnect, flush, read

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, exceptionCaught, handlerAdded, handlerRemoved, 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

exceptionCaught, handlerAdded, handlerRemoved

Constructor Details

ProtobufVarint32LengthFieldPrepender

public ProtobufVarint32LengthFieldPrepender()

Method Details

encode

protected void encode(ChannelHandlerContext ctx,
 ByteBuf msg,
 ByteBuf out)
               throws Exception

Description copied from class: MessageToByteEncoder

Encode a message into a ByteBuf. This method will be called for each written message that can be handled by this encoder.

Specified by:

encode in class MessageToByteEncoder<ByteBuf>

Parameters:

ctx - the ChannelHandlerContext which this MessageToByteEncoder belongs to

msg - the message to encode

out - the ByteBuf into which the encoded message will be written

Throws:

Exception - is thrown if an error occurs