3。编写一个Apache MINA 时间服务器

该程序的功能非常简单,就是当客户端连接到服务器的9123端口后,程序将服务器当前的时间信息以字符串的形式发送给客户端。

我们可以用Eclipse来创建编写这个程序。

(1)在Eclipse中创建一个Java项目,例如 TimeServerProject,然后将mina-core-2.0.0-M1.jar、slf4j-api.jar 和 slf4j-jdk14.jar这三个文件添加到项目的Libraries中。

(2)创建一个 MinaTimeServer 类,其内容为:

import java.io.IOException;
 import java.net.InetSocketAddress;
 import java.nio.charset.Charset;import org.apache.mina.common.IdleStatus;
 import org.apache.mina.common.IoAcceptor;
 import org.apache.mina.filter.codec.ProtocolCodecFilter;
 import org.apache.mina.filter.codec.textline.TextLineCodecFactory;
 import org.apache.mina.filter.logging.LoggingFilter;
 import org.apache.mina.transport.socket.nio.NioSocketAcceptor;public class MinaTimeServer {
 private static final int PORT = 9123;public static void main(String[] args) throws IOException {
    IoAcceptor acceptor = new NioSocketAcceptor();   acceptor.getFilterChain().addLast("logger", new LoggingFilter());
    acceptor.getFilterChain().addLast(
      "codec",
      new ProtocolCodecFilter(new TextLineCodecFactory(Charset
        .forName("UTF-8"))));   acceptor.setHandler(new TimeServerHandler());
    acceptor.getSessionConfig().setReadBufferSize(2048);
    acceptor.getSessionConfig().setIdleTime(IdleStatus.BOTH_IDLE, 10);
    acceptor.bind(new InetSocketAddress(PORT));
 }
 }

(3)创建一个 TimeServerHandler 类,其内容为:

import java.util.Date;
import org.apache.mina.common.IdleStatus;
 import org.apache.mina.common.IoHandlerAdapter;
 import org.apache.mina.common.IoSession;public class TimeServerHandler extends IoHandlerAdapter {
 @Override
 public void exceptionCaught(IoSession session, Throwable cause)
     throws Exception {
    cause.printStackTrace();
 }@Override
 public void messageReceived(IoSession session, Object message)
     throws Exception {
    String str = message.toString();
    System.out.println("Message read:");
    System.out.println(str);   Date date = new Date();
    session.write(date.toString());
    System.out.println("Message written...");
    session.close();
 }@Override
 public void sessionIdle(IoSession session, IdleStatus status)
     throws Exception {
    System.out.println("IDLE " + session.getIdleCount(status));
 }
 }

(4)编译并运行MinaTimeServer类

(5)打开您的浏览器,在地址栏中输入 http://127.0.0.1:9123/,然后回车,你就可以看到服务器的时间显示在您的浏览器内了。同时您也可以在运行MinaTimeServer的控制台窗口中看到类似下面的信息:

Message read:2008-4-11 12:22:44 org.apache.mina.filter.logging.LogLevel$4 log
信息: CREATED
2008-4-11 12:22:44 org.apache.mina.filter.logging.LogLevel$4 log
信息: OPENED
2008-4-11 12:22:44 org.apache.mina.filter.logging.LogLevel$4 log
信息: RECEIVED: HeapBuffer[pos=0 lim=261 cap=2048: 47 45 54 20 2F 20 48 54 54 50 2F 31 2E 31 0D 0A...]

GET / HTTP/1.1
Message written...
Message read:
Accept: */*
Message written...
Message read:
Accept-Language: zh-cn,en-US;q=0.5
Message written...
Message read:
UA-CPU: x86
Message written...
Message read:
Accept-Encoding: gzip, deflate
Message written...
Message read:
User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; .NET CLR 1.1.4322; .NET CLR 2.0.50727)
Message written...
Message read:
Host: 127.0.0.1:9123
Message written...
Message read:
Connection: Keep-Alive
Message written...
Message read:

Message written...
2008-4-11 12:22:44 org.apache.mina.filter.logging.LogLevel$4 log
信息: SENT: HeapBuffer[pos=0 lim=29 cap=30: 46 72 69 20 41 70 72 20 31 31 20 31 32 3A 32 32...]
2008-4-11 12:22:44 org.apache.mina.filter.logging.LogLevel$4 log
信息: SENT: HeapBuffer[pos=0 lim=0 cap=0: empty]
2008-4-11 12:22:44 org.apache.mina.filter.logging.LogLevel$4 log
信息: CLOSED

这是程序的日志信息以及,浏览器发送过来请求的HTTP头信息。

(6)或者也可以通过telnet连接服务器的9123端口,连敲两次回车,就可以看到服务器发送过来的时间信息了。