com.rabbitmq.client.impl

Class AMQCommand

java.lang.Object

com.rabbitmq.client.impl.AMQCommand

All Implemented Interfaces:

Command

public class AMQCommand
extends Object
implements Command

AMQP 0-9-1-specific implementation of Command which accumulates method, header and body from a series of frames, unless these are supplied at construction time.

Concurrency

This class is thread-safe.

Field Summary

Fields

Modifier and Type	Field and Description
static int	EMPTY_FRAME_SIZE EMPTY_FRAME_SIZE = 8 = 1 + 2 + 4 + 1 1 byte of frame type 2 bytes of channel number 4 bytes of frame payload length 1 byte of payload trailer FRAME_END byte See checkEmptyFrameSize(), an assertion checked at startup.

Constructor Summary

Constructors

Constructor and Description
AMQCommand() Construct a command ready to fill in by reading frames
AMQCommand(Method method) Construct a command with just a method, and without header or body.
AMQCommand(Method method, AMQContentHeader contentHeader, byte[] body) Construct a command with a specified method, header and body.

Method Summary

Modifier and Type	Method and Description
static void	checkPreconditions() Called to check internal code assumptions.
byte[]	getContentBody() Public API - Retrieves the body byte array that travelled as part of this Command, if any.
AMQContentHeader	getContentHeader() Public API - Retrieves the ContentHeader subclass instance held as part of this Command, if any.
Method	getMethod() Public API - Retrieves the Method held within this Command.
boolean	handleFrame(Frame f)
String	toString()
String	toString(boolean suppressBody)
void	transmit(AMQChannel channel) Sends this command down the named channel on the channel's connection, possibly in multiple frames.

Methods inherited from class java.lang.Object

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

Field Detail

EMPTY_FRAME_SIZE

public static final int EMPTY_FRAME_SIZE

EMPTY_FRAME_SIZE = 8 = 1 + 2 + 4 + 1

• 1 byte of frame type
• 2 bytes of channel number
• 4 bytes of frame payload length
• 1 byte of payload trailer FRAME_END byte

See checkEmptyFrameSize(), an assertion checked at startup.

See Also:

Constant Field Values

Constructor Detail

AMQCommand

public AMQCommand()

Construct a command ready to fill in by reading frames

AMQCommand

public AMQCommand(Method method)

Construct a command with just a method, and without header or body.

Parameters:

method - the wrapped method

AMQCommand

public AMQCommand(Method method,
                  AMQContentHeader contentHeader,
                  byte[] body)

Construct a command with a specified method, header and body.

Parameters:

method - the wrapped method

contentHeader - the wrapped content header

body - the message body data

Method Detail

getMethod

public Method getMethod()

Public API - Retrieves the Method held within this Command. Downcast to concrete (implementation-specific!) subclasses as necessary.

Specified by:

getMethod in interface Command

Returns:

the command's method.

getContentHeader

public AMQContentHeader getContentHeader()

Public API - Retrieves the ContentHeader subclass instance held as part of this Command, if any. Downcast to one of the inner classes of AMQP, for instance AMQP.BasicProperties, as appropriate.

Specified by:

getContentHeader in interface Command

Returns:

the Command's ContentHeader, or null if none

getContentBody

public byte[] getContentBody()

Public API - Retrieves the body byte array that travelled as part of this Command, if any.

Specified by:

getContentBody in interface Command

Returns:

the Command's content body, or null if none

handleFrame

public boolean handleFrame(Frame f)
                    throws IOException

Throws:

IOException

transmit

public void transmit(AMQChannel channel)
              throws IOException

Sends this command down the named channel on the channel's connection, possibly in multiple frames.

Parameters:

channel - the channel on which to transmit the command

Throws:

IOException - if an error is encountered

toString

public String toString()

Overrides:

toString in class Object

toString

public String toString(boolean suppressBody)

checkPreconditions

public static void checkPreconditions()

Called to check internal code assumptions.