io.netty.handler.codec.http.websocketx.extensions.compression.PerFrameDeflateEncoder Maven / Gradle / Ivy
/*
* 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:
*
* https://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.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 io.netty.handler.codec.http.websocketx.extensions.WebSocketExtensionFilter;
/**
* Per-frame implementation of deflate compressor.
*/
class PerFrameDeflateEncoder extends DeflateEncoder {
/**
* Constructor
*
* @param compressionLevel compression level of the compressor.
* @param windowSize maximum size of the window compressor buffer.
* @param noContext true to disable context takeover.
*/
PerFrameDeflateEncoder(int compressionLevel, int windowSize, boolean noContext) {
super(compressionLevel, windowSize, noContext, WebSocketExtensionFilter.NEVER_SKIP);
}
/**
* Constructor
*
* @param compressionLevel compression level of the compressor.
* @param windowSize maximum size of the window compressor buffer.
* @param noContext true to disable context takeover.
* @param extensionEncoderFilter extension encoder filter for per frame deflate encoder.
*/
PerFrameDeflateEncoder(int compressionLevel, int windowSize, boolean noContext,
WebSocketExtensionFilter extensionEncoderFilter) {
super(compressionLevel, windowSize, noContext, extensionEncoderFilter);
}
@Override
public boolean acceptOutboundMessage(Object msg) throws Exception {
if (!super.acceptOutboundMessage(msg)) {
return false;
}
WebSocketFrame wsFrame = (WebSocketFrame) msg;
if (extensionEncoderFilter().mustSkip(wsFrame)) {
return false;
}
return (msg instanceof TextWebSocketFrame || msg instanceof BinaryWebSocketFrame ||
msg instanceof ContinuationWebSocketFrame) &&
wsFrame.content().readableBytes() > 0 &&
(wsFrame.rsv() & WebSocketExtension.RSV1) == 0;
}
@Override
protected int rsv(WebSocketFrame msg) {
return msg.rsv() | WebSocketExtension.RSV1;
}
@Override
protected boolean removeFrameTail(WebSocketFrame msg) {
return true;
}
}