Java tutorial
/* * Copyright 2017 ZhangJiupeng * * 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 cc.agentx.client.net.nio; import cc.agentx.wrapper.Wrapper; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.channel.Channel; import io.netty.channel.ChannelFutureListener; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter; import io.netty.util.ReferenceCountUtil; import io.netty.util.internal.logging.InternalLogger; import io.netty.util.internal.logging.InternalLoggerFactory; public final class XRelayHandler extends ChannelInboundHandlerAdapter { private static final InternalLogger log; static { log = InternalLoggerFactory.getInstance(XRelayHandler.class); } private final Channel dstChannel; private final Wrapper wrapper; private final boolean uplink; public XRelayHandler(Channel dstChannel, Wrapper wrapper, boolean uplink) { this.dstChannel = dstChannel; this.wrapper = wrapper; this.uplink = uplink; } @Override public void channelRead(ChannelHandlerContext ctx, Object msg) { if (dstChannel.isActive()) { ByteBuf byteBuf = (ByteBuf) msg; try { if (!byteBuf.hasArray()) { byte[] bytes = new byte[byteBuf.readableBytes()]; byteBuf.getBytes(0, bytes); if (uplink) { dstChannel.writeAndFlush(Unpooled.wrappedBuffer(wrapper.wrap(bytes))); log.info("\tClient ==========> Target \tSend [{} bytes]", bytes.length); } else { bytes = wrapper.unwrap(bytes); if (bytes != null) { dstChannel.writeAndFlush(Unpooled.wrappedBuffer(bytes)); log.info("\tClient <========== Target \tGet [{} bytes]", bytes.length); } } } } finally { ReferenceCountUtil.release(msg); } } } @Override public void channelActive(ChannelHandlerContext ctx) { ctx.writeAndFlush(Unpooled.EMPTY_BUFFER); } @Override public void channelInactive(ChannelHandlerContext ctx) { if (dstChannel.isActive()) { if (!uplink) { log.info("\t Proxy <- Target \tDisconnect"); log.info("\tClient <- Proxy \tDisconnect"); } dstChannel.writeAndFlush(Unpooled.EMPTY_BUFFER).addListener(ChannelFutureListener.CLOSE); } } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { log.info("\t Proxy <- Target \tDisconnect"); log.info("\tClient <- Proxy \tDisconnect"); ctx.close(); } }