com.util.MyServer.java Source code

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Here is the source code for com.util.MyServer.java

Source

package com.util;

import java.net.InetSocketAddress;
import java.util.concurrent.TimeUnit;

import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelOption;
import io.netty.channel.ChannelHandler;
import io.netty.channel.EventLoopGroup;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.PooledByteBufAllocator;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;

import org.apache.logging.log4j.Logger;

/*
 * Copyright 2004-2005 the original author or authors.
 *
 * 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.
 */
public class MyServer<T> {
    public static final int ACCEPT_MULTI_CONNECTION = 1;
    public static final int ACCEPT_SINGLE_CONNECTION = 0;
    private Logger logger = null;
    private int serverPort = -1, bindSuccessCount = 0;
    private String[] bindAddress = new String[] {};
    private EventLoopGroup bossGroup = null;
    private EventLoopGroup workerGroup = null;
    private ServerBootstrap bootStrap = null;

    //-------------------------------------------------------------------------------------------   
    /**
     * It is a standard server object
     * @param serverType  
     * @param logger message logger
     */
    public MyServer(int serverType, Logger logger) {
        bootStrap = new ServerBootstrap();
        workerGroup = new NioEventLoopGroup();
        this.logger = logger;
        if (serverType == ACCEPT_MULTI_CONNECTION) {
            bossGroup = new NioEventLoopGroup();
            bootStrap.group(bossGroup, workerGroup);
        } else
            bootStrap.group(workerGroup);
        bootStrap.channel(NioServerSocketChannel.class);
    }

    /**
     * Server listening port
     * @param port no. that server to listen
     */
    public void setServerPort(int port) {
        serverPort = port;
    }

    /**
     * Set serve binding address
     * @param bindAddress
     */
    public void setBindAddress(String[] bindAddress) {
        this.bindAddress = bindAddress;
    }

    /**
     * Set the child option
     * @param childOption
     * @param value
     */
    public void setChildOption(ChannelOption<T> childOption, T value) {
        bootStrap.childOption(childOption, value);
    }

    /**
     * Set the child handler
     * @param ci child handler
     */
    public void setChildHandlers(ChannelHandler ci) {
        bootStrap.childHandler(ci);
    }

    synchronized protected void setBindStatus(ChannelFuture cf) {
        if (cf.isSuccess()) {
            bindSuccessCount++;
            InetSocketAddress localAddress = (InetSocketAddress) cf.channel().localAddress();
            logger.info("Server listen on " + localAddress.getAddress().getHostAddress() + ":"
                    + localAddress.getPort());
            if (bindSuccessCount >= bindAddress.length) {
                logger.info("Server started");
            }
        } else {
            logger.info("Server bind address failure:" + cf.cause().getMessage());
            this.stop();
        }
    }

    /**
     * Start the server
     */
    public void start() throws IllegalArgumentException {
        ServerBindListener serverBindListener = new ServerBindListener(logger, this);
        bootStrap.childOption(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT);
        /*
         * if no binding address is specified, bind "Wildcard" IP address.
         * https://docs.oracle.com/javase/7/docs/api/java/net/InetSocketAddress.html
         */
        if (bindAddress.length == 0) {
            bootStrap.bind(serverPort).addListener(serverBindListener);
        } else {
            /*
             * Looping through binding address array, bind it one by one.
             */
            for (String address : bindAddress) {
                bootStrap.bind(address, serverPort).addListener(serverBindListener);
            }
        }
    }

    /**
     * Stop the server
     */
    public void stop() {
        if (bossGroup != null) {
            bossGroup.shutdownGracefully(0, 0, TimeUnit.MILLISECONDS);
        }
        if (workerGroup != null) {
            workerGroup.shutdownGracefully(0, 0, TimeUnit.MILLISECONDS);
        }
        bossGroup = null;
        workerGroup = null;
        bootStrap = null;
        logger.debug("Server shutdown gracefully.");
    }
}