org.apache.arrow.vector.ipc.message

Class MessageChannelReader

java.lang.Object

org.apache.arrow.vector.ipc.message.MessageChannelReader

All Implemented Interfaces:

MessageReader

public class MessageChannelReader
extends Object
implements MessageReader

Reads a sequence of messages using a ReadChannel.

Constructor Summary

Constructors

Constructor and Description
MessageChannelReader(ReadChannel in) Construct from an existing ReadChannel.

Method Summary

Methods

Modifier and Type	Method and Description
long	bytesRead() Get the number of bytes read from the ReadChannel.
void	close() Close the ReadChannel.
ArrowBuf	readMessageBody(Message message, BufferAllocator allocator) Read a message body from the ReadChannel.
Message	readNextMessage() Read the next message from the ReadChannel.

Methods inherited from class java.lang.Object

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

Constructor Detail

MessageChannelReader

public MessageChannelReader(ReadChannel in)

Construct from an existing ReadChannel.

Parameters:

in - Channel to read messages from

Method Detail

readNextMessage

public Message readNextMessage()
                        throws IOException

Read the next message from the ReadChannel.

Specified by:

readNextMessage in interface MessageReader

Returns:

A Message or null if ReadChannel has no more messages, indicated by message length of 0

Throws:

IOException

readMessageBody

public ArrowBuf readMessageBody(Message message,
                       BufferAllocator allocator)
                         throws IOException

Read a message body from the ReadChannel.

Specified by:

readMessageBody in interface MessageReader

Parameters:

message - Read message that is followed by a body of data

allocator - BufferAllocator to allocate memory for body data

Returns:

ArrowBuf containing the message body data

Throws:

IOException

bytesRead

public long bytesRead()

Get the number of bytes read from the ReadChannel.

Specified by:

bytesRead in interface MessageReader

Returns:

number of bytes

close

public void close()
           throws IOException

Close the ReadChannel.

Specified by:

close in interface MessageReader

Throws:

IOException