PerMessageDeflateFunction (Undertow 2.0.30.Final API)

java.lang.Object
- io.undertow.websockets.extensions.PerMessageDeflateFunction

All Implemented Interfaces:

ExtensionFunction
```
public class PerMessageDeflateFunction
extends Object
implements ExtensionFunction
```
Implementation of permessage-deflate WebSocket Extension.
This implementation supports parameters: server_no_context_takeover, client_no_context_takeover .
This implementation does not support parameters: server_max_window_bits, client_max_window_bits .
It uses the DEFLATE implementation algorithm packaged on Deflater and Inflater classes.

Author:

Lucas Ponce

See Also:

Compression Extensions for WebSocket

Field Summary
- Fields inherited from interface io.undertow.websockets.extensions.ExtensionFunction
  RSV1, RSV2, RSV3

Constructor Summary

Constructors
Constructor and Description
`PerMessageDeflateFunction(int deflaterLevel, boolean compressContextTakeover, boolean decompressContextTakeover)` Create a new `PerMessageDeflateExtension` instance.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`dispose()` Dispose this function.
`boolean`	`hasExtensionOpCode()` Validate if current extension defines a new WebSocket Opcode.
`PooledByteBuffer`	`transformForRead(PooledByteBuffer pooledBuffer, StreamSourceFrameChannel channel, boolean lastFragmentOfMessage)` Transform the supplied buffer per this extension.
`PooledByteBuffer`	`transformForWrite(PooledByteBuffer pooledBuffer, StreamSinkFrameChannel channel, boolean lastFrame)` Transform the supplied buffer per this extension.
`int`	`writeRsv(int rsv)` Add RSV bits (RSV1, RSV2, RSV3) to the current rsv status.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - PerMessageDeflateFunction
```
public PerMessageDeflateFunction(int deflaterLevel,
                                 boolean compressContextTakeover,
                                 boolean decompressContextTakeover)
```
    Create a new PerMessageDeflateExtension instance.
    
    Parameters:
    
    deflaterLevel - the level of configuration of DEFLATE algorithm implementation
    
    compressContextTakeover - flag for compressor context takeover or without compressor context
    
    decompressContextTakeover - flag for decompressor context takeover or without decompressor context
- Method Detail
  - writeRsv
```
public int writeRsv(int rsv)
```
    Description copied from interface: ExtensionFunction
    
    Add RSV bits (RSV1, RSV2, RSV3) to the current rsv status.
    
    Specified by:
    
    writeRsv in interface ExtensionFunction
    
    Parameters:
    
    rsv - current RSV bits status
    
    Returns:
    
    rsv status
  - hasExtensionOpCode
```
public boolean hasExtensionOpCode()
```
    Description copied from interface: ExtensionFunction
    
    Validate if current extension defines a new WebSocket Opcode.
    
    Specified by:
    
    hasExtensionOpCode in interface ExtensionFunction
    
    Returns:
    
    true if current extension defines specific Opcode false is current extension does not define specific Opcode
    
    See Also:
    
    WebSocket Base Framing Protocol Reference
  - transformForWrite
```
public PooledByteBuffer transformForWrite(PooledByteBuffer pooledBuffer,
                                          StreamSinkFrameChannel channel,
                                          boolean lastFrame)
                                   throws IOException
```
    Description copied from interface: ExtensionFunction
    
    Transform the supplied buffer per this extension. The buffer can be modified in place, or a new pooled buffer can be returned (in which case be sure to free the original buffer
    
    Specified by:
    
    transformForWrite in interface ExtensionFunction
    
    Parameters:
    
    pooledBuffer - Buffer to transform
    
    channel - working channel
    
    Returns:
    
    transformed buffer (may be the same one, just with modified contents)
    
    Throws:
    
    IOException
  - transformForRead
```
public PooledByteBuffer transformForRead(PooledByteBuffer pooledBuffer,
                                         StreamSourceFrameChannel channel,
                                         boolean lastFragmentOfMessage)
                                  throws IOException
```
    Description copied from interface: ExtensionFunction
    
    Transform the supplied buffer per this extension. The buffer can be modified in place, or a new pooled buffer can be returned (in which case be sure to free the original buffer
    
    Specified by:
    
    transformForRead in interface ExtensionFunction
    
    Parameters:
    
    pooledBuffer - Buffer to transform
    
    channel - working channel
    
    lastFragmentOfMessage - If this frame is the last fragment of a message. Note that this may not be received for every message, if the message ends with an empty frame
    
    Returns:
    
    transformed buffer (may be the same one, just with modified contents)
    
    Throws:
    
    IOException
  - dispose
```
public void dispose()
```
    Description copied from interface: ExtensionFunction
    
    Dispose this function. Called upon connection closure
    
    Specified by:
    
    dispose in interface ExtensionFunction

Class PerMessageDeflateFunction

Field Summary

Fields inherited from interface io.undertow.websockets.extensions.ExtensionFunction

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

PerMessageDeflateFunction

Method Detail

writeRsv

hasExtensionOpCode

transformForWrite

transformForRead

dispose