Package alluxio.network.protocol

Class RPCMessage

java.lang.Object

alluxio.network.protocol.RPCMessage

All Implemented Interfaces:

EncodedMessage

Direct Known Subclasses:

RPCProtoMessage

@ThreadSafe
public abstract class RPCMessage
extends java.lang.Object
implements EncodedMessage

This is the main base class for all RPC messages to the DataServer. The message and type encoding scheme is adapted from the implementation found in the streaming server in Apache Spark.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	RPCMessage.Type	The possible types of RPC messages.

Constructor Summary

Constructors

Constructor	Description
RPCMessage()

Method Summary

Modifier and Type	Method	Description
static io.netty.handler.codec.ByteToMessageDecoder	createFrameDecoder()	Creates a decoder that splits up the incoming ByteBuf into new ByteBuf's according to a length field in the input.
static RPCMessage	decodeMessage(RPCMessage.Type type, io.netty.buffer.ByteBuf in)	Returns the message of message type 'type', decoded from the input ByteBuf.
DataBuffer	getPayloadDataBuffer()	Returns the data buffer of the payload.
abstract RPCMessage.Type	getType()	Returns the type of the message.
boolean	hasPayload()	Returns true if the message has a payload.
void	validate()	Validates the message.

Methods inherited from class java.lang.Object

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

Methods inherited from interface alluxio.network.protocol.EncodedMessage

encode, getEncodedLength

Constructor Detail

RPCMessage

public RPCMessage()

Method Detail

getType

public abstract RPCMessage.Type getType()

Returns the type of the message.

Returns:

the message type

validate

public void validate()

Validates the message. Throws an Exception if the message is invalid.

hasPayload

public boolean hasPayload()

Returns true if the message has a payload. The encoder will send the payload with a more efficient method.

Returns:

true if the message has a payload, false otherwise

getPayloadDataBuffer

@Nullable
public DataBuffer getPayloadDataBuffer()

Returns the data buffer of the payload.

Returns:

The DataBuffer representing the payload

createFrameDecoder

public static io.netty.handler.codec.ByteToMessageDecoder createFrameDecoder()

Creates a decoder that splits up the incoming ByteBuf into new ByteBuf's according to a length field in the input. The encoding scheme is: [(long) frame length][message payload] The frame length is NOT included in the output ByteBuf.

Returns:

the frame decoder for Netty

decodeMessage

public static RPCMessage decodeMessage(RPCMessage.Type type,
                                       io.netty.buffer.ByteBuf in)

Returns the message of message type 'type', decoded from the input ByteBuf. This must be updated to add new message types.

Parameters:

type - The type of message to decode

in - the input ByteBuf

Returns:

the decoded RPCMessage