| /* |
| * Copyright 2015-present Open Networking Foundation |
| * |
| * Licensed 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 org.onosproject.openflow.controller.impl; |
| |
| |
| import org.jboss.netty.buffer.ChannelBuffer; |
| import org.jboss.netty.channel.Channel; |
| import org.jboss.netty.channel.ChannelHandlerContext; |
| import org.jboss.netty.handler.codec.frame.FrameDecoder; |
| import org.projectfloodlight.openflow.protocol.OFFactories; |
| import org.projectfloodlight.openflow.protocol.OFMessage; |
| import org.projectfloodlight.openflow.protocol.OFMessageReader; |
| |
| /** |
| * Decode an openflow message from a Channel, for use in a netty pipeline. |
| */ |
| public class OFMessageDecoder extends FrameDecoder { |
| |
| @Override |
| protected Object decode(ChannelHandlerContext ctx, Channel channel, |
| ChannelBuffer buffer) throws Exception { |
| if (!channel.isConnected()) { |
| // In testing, I see decode being called AFTER decode last. |
| // This check avoids that from reading corrupted frames |
| return null; |
| } |
| |
| // Note that a single call to decode results in reading a single |
| // OFMessage from the channel buffer, which is passed on to, and processed |
| // by, the controller (in OFChannelHandler). |
| // This is different from earlier behavior (with the original openflowj), |
| // where we parsed all the messages in the buffer, before passing on |
| // a list of the parsed messages to the controller. |
| // The performance *may or may not* not be as good as before. |
| OFMessageReader<OFMessage> reader = OFFactories.getGenericReader(); |
| OFMessage message = reader.readFrom(buffer); |
| |
| return message; |
| } |
| |
| } |