Package org.apache.tomcat.websocket

Class PerMessageDeflate

java.lang.Object

org.apache.tomcat.websocket.PerMessageDeflate

All Implemented Interfaces:

Transformation

public class PerMessageDeflate
extends Object
implements Transformation

Field Summary

Fields

Modifier and Type	Field	Description
static final String	NAME

Method Summary

Modifier and Type	Method	Description
void	close()	Clean-up any resources that were used by the transformation.
Extension	getExtensionResponse()	Obtain the extension that describes the information to be returned to the client.
TransformationResult	getMoreData(byte opCode, boolean fin, int rsv, ByteBuffer dest)	Obtain more input data.
List<org.apache.tomcat.websocket.MessagePart>	sendMessagePart(List<org.apache.tomcat.websocket.MessagePart> uncompressedParts)	Takes the provided list of messages, transforms them, passes the transformed list on to the next transformation (if any) and then returns the resulting list of message parts after all of the transformations have been applied.
void	setNext(Transformation t)	Sets the next transformation in the pipeline.
boolean	validateRsv(int rsv, byte opCode)	Validates the RSV and opcode combination (assumed to have been extracted from a WebSocket Frame) for this extension.
boolean	validateRsvBits(int i)	Validate that the RSV bit(s) required by this transformation are not being used by another extension.

Methods inherited from class java.lang.Object

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

Field Details

NAME

public static final String NAME

See Also:

• Constant Field Values

Method Details

getMoreData

public TransformationResult getMoreData(byte opCode,
 boolean fin,
 int rsv,
 ByteBuffer dest)
                                 throws IOException

Description copied from interface: Transformation

Obtain more input data.

Specified by:

getMoreData in interface Transformation

Parameters:

opCode - The opcode for the frame currently being processed

fin - Is this the final frame in this WebSocket message?

rsv - The reserved bits for the frame currently being processed

dest - The buffer in which the data is to be written

Returns:

The result of trying to read more data from the transform

Throws:

IOException - If an I/O error occurs while reading data from the transform

validateRsv

public boolean validateRsv(int rsv,
 byte opCode)

Description copied from interface: Transformation

Validates the RSV and opcode combination (assumed to have been extracted from a WebSocket Frame) for this extension. The implementation is expected to unset any RSV bits it has validated before passing the remaining RSV bits to the next transformation in the pipeline.

Specified by:

validateRsv in interface Transformation

Parameters:

rsv - The RSV bits received as an int in the range zero to seven with RSV1 as the MSB and RSV3 as the LSB

opCode - The opCode received

Returns:

true if the RSV is valid otherwise false

getExtensionResponse

public Extension getExtensionResponse()

Description copied from interface: Transformation

Obtain the extension that describes the information to be returned to the client.

Specified by:

getExtensionResponse in interface Transformation

Returns:

The extension information that describes the parameters that have been agreed for this transformation

setNext

public void setNext(Transformation t)

Description copied from interface: Transformation

Sets the next transformation in the pipeline.

Specified by:

setNext in interface Transformation

Parameters:

t - The next transformation

validateRsvBits

public boolean validateRsvBits(int i)

Description copied from interface: Transformation

Validate that the RSV bit(s) required by this transformation are not being used by another extension. The implementation is expected to set any bits it requires before passing the set of in-use bits to the next transformation.

Specified by:

validateRsvBits in interface Transformation

Parameters:

i - The RSV bits marked as in use so far as an int in the range zero to seven with RSV1 as the MSB and RSV3 as the LSB

Returns:

true if the combination of RSV bits used by the transformations in the pipeline do not conflict otherwise false

sendMessagePart

public List<org.apache.tomcat.websocket.MessagePart> sendMessagePart(List<org.apache.tomcat.websocket.MessagePart> uncompressedParts)
                                                              throws IOException

Description copied from interface: Transformation

Takes the provided list of messages, transforms them, passes the transformed list on to the next transformation (if any) and then returns the resulting list of message parts after all of the transformations have been applied.

Specified by:

sendMessagePart in interface Transformation

Parameters:

uncompressedParts - The list of messages to be transformed

Returns:

The list of messages after this any any subsequent transformations have been applied. The size of the returned list may be bigger or smaller than the size of the input list

Throws:

IOException - If an error occurs during the transformation of the message parts

close

public void close()

Description copied from interface: Transformation

Clean-up any resources that were used by the transformation.

Specified by:

close in interface Transformation