/*
* Copyright 2014 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package io.netty.handler.codec.http.websocketx.extensions.compression;
import io.netty.channel.
ChannelHandlerContext;
import io.netty.handler.codec.http.websocketx.
BinaryWebSocketFrame;
import io.netty.handler.codec.http.websocketx.
ContinuationWebSocketFrame;
import io.netty.handler.codec.http.websocketx.
TextWebSocketFrame;
import io.netty.handler.codec.http.websocketx.
WebSocketFrame;
import io.netty.handler.codec.http.websocketx.extensions.
WebSocketExtension;
import java.util.
List;
/**
* Per-message implementation of deflate compressor.
*/
class
PerMessageDeflateEncoder extends
DeflateEncoder {
private boolean
compressing;
/**
* Constructor
* @param compressionLevel compression level of the compressor.
* @param windowSize maximum size of the window compressor buffer.
* @param noContext true to disable context takeover.
*/
public
PerMessageDeflateEncoder(int
compressionLevel, int
windowSize, boolean
noContext) {
super(
compressionLevel,
windowSize,
noContext);
}
@
Override
public boolean
acceptOutboundMessage(
Object msg) throws
Exception {
return ((
msg instanceof
TextWebSocketFrame ||
msg instanceof
BinaryWebSocketFrame) &&
(((
WebSocketFrame)
msg).
rsv() &
WebSocketExtension.
RSV1) == 0) ||
(
msg instanceof
ContinuationWebSocketFrame &&
compressing);
}
@
Override
protected int
rsv(
WebSocketFrame msg) {
return
msg instanceof
TextWebSocketFrame ||
msg instanceof
BinaryWebSocketFrame ?
msg.
rsv() |
WebSocketExtension.
RSV1 :
msg.
rsv();
}
@
Override
protected boolean
removeFrameTail(
WebSocketFrame msg) {
return
msg.
isFinalFragment();
}
@
Override
protected void
encode(
ChannelHandlerContext ctx,
WebSocketFrame msg,
List<
Object>
out) throws
Exception {
super.encode(
ctx,
msg,
out);
if (
msg.
isFinalFragment()) {
compressing = false;
} else if (
msg instanceof
TextWebSocketFrame ||
msg instanceof
BinaryWebSocketFrame) {
compressing = true;
}
}
}