程序包 com.mysql.cj.protocol

接口 MessageReader<H extends MessageHeader,M extends Message>

所有已知实现类:

DebugBufferingPacketReader, MultiPacketReader, SimplePacketReader, SyncMessageReader, TimeTrackingPacketReader, TracingPacketReader

public interface MessageReader<H extends MessageHeader,M extends Message>

方法概要

修饰符和类型	方法	说明
default byte	getMessageSequence()	Get last message sequence number, as it was stored by readHeader().
default H	probeHeader()	Read the next message header from server, possibly blocking indefinitely until the message is received, and cache it so that the next readHeader() return the same header.
default M	probeMessage(Optional<M> reuse, H header)	Read message from server into to the given Message instance or into the new one if not present and cache it so that the next readMessage(Optional, MessageHeader) return the same message.
default void	pushMessageListener(MessageListener<M> l)	Queue a MessageListener to receive messages delivered asynchronously.
H	readHeader()	Read the next message header from server, possibly blocking indefinitely until the message is received.
default M	readMessage(Optional<M> reuse, int expectedType)	Read message from server into to the given Message instance or into the new one if not present.
M	readMessage(Optional<M> reuse, H header)	Read message from server into to the given Message instance or into the new one if not present.
default void	resetMessageSequence()	Set stored message sequence number to 0.
default void	start()	Start reading messages reader from the provided channel.
default void	stopAfterNextMessage()	Signal to the reader that it should stop reading messages after reading the next message.
default MessageReader<H,M>	undecorate()	Return the previous MessageReader instance from the decorators chain or the current MessageReader if it is the first entry in a chain.
default MessageReader<H,M>	undecorateAll()	Return a MessageReader instance free of decorators.

方法详细资料

readHeader

H readHeader()
      throws IOException

Read the next message header from server, possibly blocking indefinitely until the message is received.

返回:

MessageHeader of the next message

抛出:

IOException - if an error occurs

probeHeader

default H probeHeader()
               throws IOException

Read the next message header from server, possibly blocking indefinitely until the message is received, and cache it so that the next readHeader() return the same header.

返回:

MessageHeader of the next message

抛出:

IOException - if an error occurs

readMessage

M readMessage(Optional<M> reuse,
              H header)
       throws IOException

Read message from server into to the given Message instance or into the new one if not present. For asynchronous channel it synchronously reads the next message in the stream, blocking until the message is read fully. Could throw CJCommunicationsException wrapping an IOException during read or parse

参数:

reuse - Message object to reuse. May be ignored by implementation.

header - MessageHeader instance

返回:

Message instance

抛出:

IOException - if an error occurs

probeMessage

default M probeMessage(Optional<M> reuse,
                       H header)
                throws IOException

Read message from server into to the given Message instance or into the new one if not present and cache it so that the next readMessage(Optional, MessageHeader) return the same message. For asynchronous channel it synchronously reads the next message in the stream, blocking until the message is read fully. Could throw CJCommunicationsException wrapping an IOException during read or parse

参数:

reuse - Message object to reuse. May be ignored by implementation.

header - MessageHeader instance

返回:

Message instance

抛出:

IOException - if an error occurs

readMessage

default M readMessage(Optional<M> reuse,
                      int expectedType)
               throws IOException

Read message from server into to the given Message instance or into the new one if not present. For asynchronous channel it synchronously reads the next message in the stream, blocking until the message is read fully. Could throw WrongArgumentException if the expected message type is not the next message (exception will be thrown in *caller* context).

参数:

reuse - Message object to reuse. May be ignored by implementation.

expectedType - Expected type of message.

返回:

Message instance

抛出:

IOException - if an error occurs

pushMessageListener

default void pushMessageListener(MessageListener<M> l)

Queue a MessageListener to receive messages delivered asynchronously.

参数:

l - MessageListener

getMessageSequence

default byte getMessageSequence()

Get last message sequence number, as it was stored by readHeader().

返回:

number

resetMessageSequence

default void resetMessageSequence()

Set stored message sequence number to 0.

undecorateAll

default MessageReader<H,M> undecorateAll()

Return a MessageReader instance free of decorators.

返回:

MessageReader

undecorate

default MessageReader<H,M> undecorate()

Return the previous MessageReader instance from the decorators chain or the current MessageReader if it is the first entry in a chain.

返回:

MessageReader

start

default void start()

Start reading messages reader from the provided channel.

stopAfterNextMessage

default void stopAfterNextMessage()

Signal to the reader that it should stop reading messages after reading the next message.