mina 使用手记3

在上一篇中，通过一个简单的例子，得以管中窥豹，了解了Mina的基本编写方法。在MinaTimeServer演示程序中，我们添加了两个过滤 器，一个是日志过滤器LoggingFilter，一个是文本编解码过滤器。前者实现日志信息的自动处理，后者实现对按行读写的文本数据的编码和解码。

其中LoggingFilter默认的是slf4j，它是一个日志Facade，实际并不实现真正的日志处理功能，它在程序运行时自动判断 classpath中加载的日志组件，比如：log4j/Logback/JUL等，确定之后调用真正的日志组件实现真正的日志处理操作。这一点对于组件 式的程序，很明显是非常灵活的，因为你并不知道用户的实际环境中使用的是log4j还是JUL，或者是Logback等，但是为了实现自动识 别，slf4j默认了log配置文件的加载位置，让我觉得十分不便。

我自己的所有系统中，都使用是log4j（他的替代产品Logback已经出来了，据说性能更强），我一般喜欢把所有配置文件包括 log4j.properties都放在conf目录下，以便管理。因此，对于slf4j中需要把log4j.properties放在src文件夹下非 常不习惯，对于以后管理也容易引起混乱。所以，我希望能直接实现自己的log4j过滤器，按以前的方式使用。我们观察一下LoggingFilter过滤 器的源代码，如下所示：

view plain copy to clipboard print ?

1. public   class  LoggingFilter  extends  IoFilterAdapter{...}  

public class LoggingFilter extends IoFilterAdapter{...}

LoggingFilter继承自IoFilterAdapter，它是java模型中的适配器模式，是对接口IoFilter的包装。我们可以模仿LoggingFilter，实现自己的Log4jFilter类：

view plain copy to clipboard print ?

1. import  org.apache.log4j.Level;  
2. import  org.apache.log4j.Logger;  
3. import  org.apache.mina.core.filterchain.IoFilterAdapter;  
4. import  org.apache.mina.core.session.IdleStatus;  
5. import  org.apache.mina.core.session.IoSession;  
6. import  org.apache.mina.core.write.WriteRequest;  
7. import  org.apache.mina.filter.logging.LogLevel;  
8. import  org.slf4j.helpers.MessageFormatter;  
9. public   class  Log4jFilter  extends  IoFilterAdapter {  
10.     /** The logger name */   
11.     private   final  String name;  
12.       
13.     /** The logger */   
14.     private   final  Logger logger;  
15.       
16.     /** The log level for the exceptionCaught event. Default to WARN. */   
17.     private  LogLevel exceptionCaughtLevel = LogLevel.WARN;  
18.       
19.     /** The log level for the messageSent event. Default to INFO. */   
20.     private  LogLevel messageSentLevel = LogLevel.INFO;  
21.       
22.     /** The log level for the messageReceived event. Default to INFO. */   
23.     private  LogLevel messageReceivedLevel = LogLevel.INFO;  
24.       
25.     /** The log level for the sessionCreated event. Default to INFO. */   
26.     private  LogLevel sessionCreatedLevel = LogLevel.INFO;  
27.       
28.     /** The log level for the sessionOpened event. Default to INFO. */   
29.     private  LogLevel sessionOpenedLevel = LogLevel.INFO;  
30.       
31.     /** The log level for the sessionIdle event. Default to INFO. */   
32.     private  LogLevel sessionIdleLevel = LogLevel.INFO;  
33.       
34.     /** The log level for the sessionClosed event. Default to INFO. */   
35.     private  LogLevel sessionClosedLevel = LogLevel.INFO;  
36.       
37.     /**  
38.      * Default Constructor.  
39.      */   
40.     public  Log4jFilter(Logger logger) {  
41.         this .logger=logger;  
42.         this .name=logger.getName();  
43.     }  
44.       
45.        
46.        
47.     /**  
48.      * @return The logger's name  
49.      */   
50.     public  String getName() {  
51.         return  name;  
52.     }  
53.       
54.     /**  
55.      * Log if the logger and the current event log level are compatible. We log  
56.      * a message and an exception.  
57.      *  
58.      * @param eventLevel the event log level as requested by the user  
59.      * @param message the message to log  
60.      * @param cause the exception cause to log  
61.      */   
62.     private   void  log(LogLevel eventLevel, String message, Throwable cause) {  
63.         if  (eventLevel == LogLevel.TRACE) {  
64.             logger.trace(message, cause);  
65.         } else   if  (eventLevel.getLevel() > LogLevel.INFO.getLevel()) {  
66.             logger.info(message, cause);  
67.         } else   if  (eventLevel.getLevel() > LogLevel.WARN.getLevel()) {  
68.             logger.warn(message, cause);  
69.         } else   if  (eventLevel.getLevel() > LogLevel.ERROR.getLevel()) {  
70.             logger.error(message, cause);  
71.         }  
72.     }  
73.     /**  
74.      * Log if the logger and the current event log level are compatible. We log  
75.      * a formated message and its parameters.  
76.      *  
77.      * @param eventLevel the event log level as requested by the user  
78.      * @param message the formated message to log  
79.      * @param param the parameter injected into the message  
80.      */   
81.     private   void  log(LogLevel eventLevel, String message, Object param) {  
82.         String msgStr = MessageFormatter.format(message, param);  
83.         if  (eventLevel == LogLevel.TRACE) {  
84.             logger.log(name, Level.TRACE, msgStr, null );  
85.               
86.         } else   if  (eventLevel.getLevel() > LogLevel.INFO.getLevel()) {  
87.             logger.log(name, Level.INFO, msgStr, null );  
88.         } else   if  (eventLevel.getLevel() > LogLevel.WARN.getLevel()) {  
89.             logger.log(name, Level.WARN, msgStr, null );  
90.         } else   if  (eventLevel.getLevel() > LogLevel.ERROR.getLevel()) {  
91.             logger.log(name, Level.ERROR, msgStr, null );  
92.         }  
93.     }  
94.     /**  
95.      * Log if the logger and the current event log level are compatible. We log  
96.      * a simple message.  
97.      *  
98.      * @param eventLevel the event log level as requested by the user  
99.      * @param message the message to log  
100.      */   
101.     private   void  log(LogLevel eventLevel, String message) {  
102.         if  (eventLevel == LogLevel.TRACE) {  
103.             logger.trace(message);  
104.         } else   if  (eventLevel.getLevel() > LogLevel.INFO.getLevel()) {  
105.             logger.info(message);  
106.         } else   if  (eventLevel.getLevel() > LogLevel.WARN.getLevel()) {  
107.             logger.warn(message);  
108.         } else   if  (eventLevel.getLevel() > LogLevel.ERROR.getLevel()) {  
109.             logger.error(message);  
110.         }  
111.     }  
112.     @Override   
113.     public   void  exceptionCaught(NextFilter nextFilter, IoSession session,  
114.             Throwable cause) throws  Exception {  
115.         log(exceptionCaughtLevel, "EXCEPTION :" , cause);  
116.         nextFilter.exceptionCaught(session, cause);  
117.     }  
118.     @Override   
119.     public   void  messageReceived(NextFilter nextFilter, IoSession session,  
120.             Object message) throws  Exception {  
121.         log(messageReceivedLevel, "RECEIVED: {}" , message );  
122.         nextFilter.messageReceived(session, message);  
123.     }  
124.     @Override   
125.     public   void  messageSent(NextFilter nextFilter, IoSession session,  
126.             WriteRequest writeRequest) throws  Exception {  
127.         log(messageSentLevel, "SENT: {}" , writeRequest.getMessage() );  
128.         nextFilter.messageSent(session, writeRequest);  
129.     }  
130.     @Override   
131.     public   void  sessionCreated(NextFilter nextFilter, IoSession session)  
132.             throws  Exception {  
133.         log(sessionCreatedLevel, "CREATED" );  
134.         nextFilter.sessionCreated(session);  
135.     }  
136.     @Override   
137.     public   void  sessionOpened(NextFilter nextFilter, IoSession session)  
138.     throws  Exception {  
139.         log(sessionOpenedLevel, "OPENED" );  
140.         nextFilter.sessionOpened(session);  
141.     }  
142.     @Override   
143.     public   void  sessionIdle(NextFilter nextFilter, IoSession session,  
144.             IdleStatus status) throws  Exception {  
145.         log(sessionIdleLevel, "IDLE" );  
146.         nextFilter.sessionIdle(session, status);  
147.     }  
148.     @Override   
149.     public   void  sessionClosed(NextFilter nextFilter, IoSession session)  throws  Exception {  
150.         log(sessionClosedLevel, "CLOSED" );  
151.         nextFilter.sessionClosed(session);  
152.     }  
153.       
154.     /**  
155.      * Set the LogLevel for the ExceptionCaught event.  
156.      *  
157.      * @param level The LogLevel to set  
158.      */   
159.     public   void  setExceptionCaughtLoglevel(LogLevel level) {  
160.         exceptionCaughtLevel = level;  
161.     }  
162.       
163.     /**  
164.      * Get the LogLevel for the ExceptionCaught event.  
165.      *  
166.      * @return The LogLevel for the ExceptionCaught eventType  
167.      */   
168.     public  LogLevel getExceptionCaughtLoglevel() {  
169.         return  exceptionCaughtLevel;  
170.     }  
171.       
172.     /**  
173.      * Set the LogLevel for the MessageReceived event.  
174.      *  
175.      * @param level The LogLevel to set  
176.      */   
177.     public   void  setMessageReceivedLoglevel(LogLevel level) {  
178.         messageReceivedLevel = level;  
179.     }  
180.       
181.     /**  
182.      * Get the LogLevel for the MessageReceived event.  
183.      *  
184.      * @return The LogLevel for the MessageReceived eventType  
185.      */   
186.     public  LogLevel getMessageReceivedLoglevel() {  
187.         return  messageReceivedLevel;  
188.     }  
189.       
190.     /**  
191.      * Set the LogLevel for the MessageSent event.  
192.      *  
193.      * @param level The LogLevel to set  
194.      */   
195.     public   void  setMessageSentLoglevel(LogLevel level) {  
196.         messageSentLevel = level;  
197.     }  
198.       
199.     /**  
200.      * Get the LogLevel for the MessageSent event.  
201.      *  
202.      * @return The LogLevel for the MessageSent eventType  
203.      */   
204.     public  LogLevel getMessageSentLoglevel() {  
205.         return  messageSentLevel;  
206.     }  
207.       
208.     /**  
209.      * Set the LogLevel for the SessionCreated event.  
210.      *  
211.      * @param level The LogLevel to set  
212.      */   
213.     public   void  setSessionCreatedLoglevel(LogLevel level) {  
214.         sessionCreatedLevel = level;  
215.     }  
216.       
217.     /**  
218.      * Get the LogLevel for the SessionCreated event.  
219.      *  
220.      * @return The LogLevel for the SessionCreated eventType  
221.      */   
222.     public  LogLevel getSessionCreatedLoglevel() {  
223.         return  sessionCreatedLevel;  
224.     }  
225.       
226.     /**  
227.      * Set the LogLevel for the SessionOpened event.  
228.      *  
229.      * @param level The LogLevel to set  
230.      */   
231.     public   void  setSessionOpenedLoglevel(LogLevel level) {  
232.         sessionOpenedLevel = level;  
233.     }  
234.       
235.     /**  
236.      * Get the LogLevel for the SessionOpened event.  
237.      *  
238.      * @return The LogLevel for the SessionOpened eventType  
239.      */   
240.     public  LogLevel getSessionOpenedLoglevel() {  
241.         return  sessionOpenedLevel;  
242.     }  
243.       
244.     /**  
245.      * Set the LogLevel for the SessionIdle event.  
246.      *  
247.      * @param level The LogLevel to set  
248.      */   
249.     public   void  setSessionIdleLoglevel(LogLevel level) {  
250.         sessionIdleLevel = level;  
251.     }  
252.       
253.     /**  
254.      * Get the LogLevel for the SessionIdle event.  
255.      *  
256.      * @return The LogLevel for the SessionIdle eventType  
257.      */   
258.     public  LogLevel getSessionIdleLoglevel() {  
259.         return  sessionIdleLevel;  
260.     }  
261.       
262.     /**  
263.      * Set the LogLevel for the SessionClosed event.  
264.      *  
265.      * @param level The LogLevel to set  
266.      */   
267.     public   void  setSessionClosedLoglevel(LogLevel level) {  
268.         sessionClosedLevel = level;  
269.     }  
270.     /**  
271.      * Get the LogLevel for the SessionClosed event.  
272.      *  
273.      * @return The LogLevel for the SessionClosed eventType  
274.      */   
275.     public  LogLevel getSessionClosedLoglevel() {  
276.         return  sessionClosedLevel;  
277.     }  
278. }  

import org.apache.log4j.Level; import org.apache.log4j.Logger; import org.apache.mina.core.filterchain.IoFilterAdapter; import org.apache.mina.core.session.IdleStatus; import org.apache.mina.core.session.IoSession; import org.apache.mina.core.write.WriteRequest; import org.apache.mina.filter.logging.LogLevel; import org.slf4j.helpers.MessageFormatter; public class Log4jFilter extends IoFilterAdapter { /** The logger name */ private final String name; /** The logger */ private final Logger logger; /** The log level for the exceptionCaught event. Default to WARN. */ private LogLevel exceptionCaughtLevel = LogLevel.WARN; /** The log level for the messageSent event. Default to INFO. */ private LogLevel messageSentLevel = LogLevel.INFO; /** The log level for the messageReceived event. Default to INFO. */ private LogLevel messageReceivedLevel = LogLevel.INFO; /** The log level for the sessionCreated event. Default to INFO. */ private LogLevel sessionCreatedLevel = LogLevel.INFO; /** The log level for the sessionOpened event. Default to INFO. */ private LogLevel sessionOpenedLevel = LogLevel.INFO; /** The log level for the sessionIdle event. Default to INFO. */ private LogLevel sessionIdleLevel = LogLevel.INFO; /** The log level for the sessionClosed event. Default to INFO. */ private LogLevel sessionClosedLevel = LogLevel.INFO; /** * Default Constructor. */ public Log4jFilter(Logger logger) { this.logger=logger; this.name=logger.getName(); } /** * @return The logger's name */ public String getName() { return name; } /** * Log if the logger and the current event log level are compatible. We log * a message and an exception. * * @param eventLevel the event log level as requested by the user * @param message the message to log * @param cause the exception cause to log */ private void log(LogLevel eventLevel, String message, Throwable cause) { if (eventLevel == LogLevel.TRACE) { logger.trace(message, cause); } else if (eventLevel.getLevel() > LogLevel.INFO.getLevel()) { logger.info(message, cause); } else if (eventLevel.getLevel() > LogLevel.WARN.getLevel()) { logger.warn(message, cause); } else if (eventLevel.getLevel() > LogLevel.ERROR.getLevel()) { logger.error(message, cause); } } /** * Log if the logger and the current event log level are compatible. We log * a formated message and its parameters. * * @param eventLevel the event log level as requested by the user * @param message the formated message to log * @param param the parameter injected into the message */ private void log(LogLevel eventLevel, String message, Object param) { String msgStr = MessageFormatter.format(message, param); if (eventLevel == LogLevel.TRACE) { logger.log(name, Level.TRACE, msgStr, null); } else if (eventLevel.getLevel() > LogLevel.INFO.getLevel()) { logger.log(name, Level.INFO, msgStr, null); } else if (eventLevel.getLevel() > LogLevel.WARN.getLevel()) { logger.log(name, Level.WARN, msgStr, null); } else if (eventLevel.getLevel() > LogLevel.ERROR.getLevel()) { logger.log(name, Level.ERROR, msgStr, null); } } /** * Log if the logger and the current event log level are compatible. We log * a simple message. * * @param eventLevel the event log level as requested by the user * @param message the message to log */ private void log(LogLevel eventLevel, String message) { if (eventLevel == LogLevel.TRACE) { logger.trace(message); } else if (eventLevel.getLevel() > LogLevel.INFO.getLevel()) { logger.info(message); } else if (eventLevel.getLevel() > LogLevel.WARN.getLevel()) { logger.warn(message); } else if (eventLevel.getLevel() > LogLevel.ERROR.getLevel()) { logger.error(message); } } @Override public void exceptionCaught(NextFilter nextFilter, IoSession session, Throwable cause) throws Exception { log(exceptionCaughtLevel, "EXCEPTION :", cause); nextFilter.exceptionCaught(session, cause); } @Override public void messageReceived(NextFilter nextFilter, IoSession session, Object message) throws Exception { log(messageReceivedLevel, "RECEIVED: {}", message ); nextFilter.messageReceived(session, message); } @Override public void messageSent(NextFilter nextFilter, IoSession session, WriteRequest writeRequest) throws Exception { log(messageSentLevel, "SENT: {}", writeRequest.getMessage() ); nextFilter.messageSent(session, writeRequest); } @Override public void sessionCreated(NextFilter nextFilter, IoSession session) throws Exception { log(sessionCreatedLevel, "CREATED"); nextFilter.sessionCreated(session); } @Override public void sessionOpened(NextFilter nextFilter, IoSession session) throws Exception { log(sessionOpenedLevel, "OPENED"); nextFilter.sessionOpened(session); } @Override public void sessionIdle(NextFilter nextFilter, IoSession session, IdleStatus status) throws Exception { log(sessionIdleLevel, "IDLE"); nextFilter.sessionIdle(session, status); } @Override public void sessionClosed(NextFilter nextFilter, IoSession session) throws Exception { log(sessionClosedLevel, "CLOSED"); nextFilter.sessionClosed(session); } /** * Set the LogLevel for the ExceptionCaught event. * * @param level The LogLevel to set */ public void setExceptionCaughtLoglevel(LogLevel level) { exceptionCaughtLevel = level; } /** * Get the LogLevel for the ExceptionCaught event. * * @return The LogLevel for the ExceptionCaught eventType */ public LogLevel getExceptionCaughtLoglevel() { return exceptionCaughtLevel; } /** * Set the LogLevel for the MessageReceived event. * * @param level The LogLevel to set */ public void setMessageReceivedLoglevel(LogLevel level) { messageReceivedLevel = level; } /** * Get the LogLevel for the MessageReceived event. * * @return The LogLevel for the MessageReceived eventType */ public LogLevel getMessageReceivedLoglevel() { return messageReceivedLevel; } /** * Set the LogLevel for the MessageSent event. * * @param level The LogLevel to set */ public void setMessageSentLoglevel(LogLevel level) { messageSentLevel = level; } /** * Get the LogLevel for the MessageSent event. * * @return The LogLevel for the MessageSent eventType */ public LogLevel getMessageSentLoglevel() { return messageSentLevel; } /** * Set the LogLevel for the SessionCreated event. * * @param level The LogLevel to set */ public void setSessionCreatedLoglevel(LogLevel level) { sessionCreatedLevel = level; } /** * Get the LogLevel for the SessionCreated event. * * @return The LogLevel for the SessionCreated eventType */ public LogLevel getSessionCreatedLoglevel() { return sessionCreatedLevel; } /** * Set the LogLevel for the SessionOpened event. * * @param level The LogLevel to set */ public void setSessionOpenedLoglevel(LogLevel level) { sessionOpenedLevel = level; } /** * Get the LogLevel for the SessionOpened event. * * @return The LogLevel for the SessionOpened eventType */ public LogLevel getSessionOpenedLoglevel() { return sessionOpenedLevel; } /** * Set the LogLevel for the SessionIdle event. * * @param level The LogLevel to set */ public void setSessionIdleLoglevel(LogLevel level) { sessionIdleLevel = level; } /** * Get the LogLevel for the SessionIdle event. * * @return The LogLevel for the SessionIdle eventType */ public LogLevel getSessionIdleLoglevel() { return sessionIdleLevel; } /** * Set the LogLevel for the SessionClosed event. * * @param level The LogLevel to set */ public void setSessionClosedLoglevel(LogLevel level) { sessionClosedLevel = level; } /** * Get the LogLevel for the SessionClosed event. * * @return The LogLevel for the SessionClosed eventType */ public LogLevel getSessionClosedLoglevel() { return sessionClosedLevel; } }

其实代码很类似，在MinaTimeServer中使用Log4jFilter使使看：

view plain copy to clipboard print ?

1. package  com.gftech.mytool.mina;  
2. import  java.io.IOException;  
3. import  java.net.InetSocketAddress;  
4. import  java.nio.charset.Charset;  
5. import  java.util.Date;  
6. import  org.apache.log4j.Logger;  
7. import  org.apache.log4j.PropertyConfigurator;  
8. import  org.apache.mina.core.service.IoAcceptor;  
9. import  org.apache.mina.core.service.IoHandlerAdapter;  
10. import  org.apache.mina.core.session.IdleStatus;  
11. import  org.apache.mina.core.session.IoSession;  
12. import  org.apache.mina.filter.codec.ProtocolCodecFilter;  
13. import  org.apache.mina.filter.codec.textline.TextLineCodecFactory;  
14. import  org.apache.mina.transport.socket.nio.NioSocketAcceptor;  
15. public   class  MinaTimeServer {  
16.     private   static   final   int  PORT =  2500 ;  
17.     // static Logger logger = LoggerFactory.getLogger(MinaTimeServer.class);   
18.     static  Logger logger = Logger.getLogger(MinaTimeServer. class );  
19.     public   static   void  main(String[] args)  throws  IOException {  
20.         PropertyConfigurator.configure("conf//log4j.properties" );  
21.         IoAcceptor acceptor = new  NioSocketAcceptor();  
22.         // LoggingFilter lf = new LoggingFilter("testLog");   
23.         Log4jFilter lf = new  Log4jFilter(logger);  
24.         acceptor.getFilterChain().addLast("logger" , lf);  
25.         acceptor.getFilterChain().addLast("codec" ,  new  ProtocolCodecFilter( new  TextLineCodecFactory(Charset.forName( "GBK" ))));  
26.         acceptor.setHandler(new  TimeServerHandler());  
27.         acceptor.getSessionConfig().setReadBufferSize(10 );  
28.         acceptor.getSessionConfig().setIdleTime(IdleStatus.BOTH_IDLE, 10 );  
29.         acceptor.bind(new  InetSocketAddress(PORT));  
30.         System.out.println("start server ..." );  
31.     }  
32. }  
33. class  TimeServerHandler  extends  IoHandlerAdapter {  
34.     // static Logger logger = LoggerFactory.getLogger(TimeServerHandler.class);   
35.     static  Logger logger = Logger.getLogger(TimeServerHandler. class );  
36.     @Override   
37.     public   void  exceptionCaught(IoSession session, Throwable cause)  throws  Exception {  
38.         cause.printStackTrace();  
39.     }  
40.     @Override   
41.     public   void  messageReceived(IoSession session, Object message)  throws  Exception {  
42.         String str = message.toString();  
43.         if  (str.trim().equalsIgnoreCase( "quit" )) {  
44.             session.close(true );  
45.             return ;  
46.         }  
47.         logger.debug("Rec:"  + str);  
48.         Date date = new  Date();  
49.         session.write(date.toString());  
50.         logger.debug("Message written..." );  
51.     }  
52.     @Override   
53.     public   void  sessionIdle(IoSession session, IdleStatus status)  throws  Exception {  
54.         logger.debug("IDLE "  + session.getIdleCount(status));  
55.     }  
56. }  

package com.gftech.mytool.mina; import java.io.IOException; import java.net.InetSocketAddress; import java.nio.charset.Charset; import java.util.Date; import org.apache.log4j.Logger; import org.apache.log4j.PropertyConfigurator; import org.apache.mina.core.service.IoAcceptor; import org.apache.mina.core.service.IoHandlerAdapter; import org.apache.mina.core.session.IdleStatus; import org.apache.mina.core.session.IoSession; import org.apache.mina.filter.codec.ProtocolCodecFilter; import org.apache.mina.filter.codec.textline.TextLineCodecFactory; import org.apache.mina.transport.socket.nio.NioSocketAcceptor; public class MinaTimeServer { private static final int PORT = 2500; // static Logger logger = LoggerFactory.getLogger(MinaTimeServer.class); static Logger logger = Logger.getLogger(MinaTimeServer.class); public static void main(String[] args) throws IOException { PropertyConfigurator.configure("conf//log4j.properties"); IoAcceptor acceptor = new NioSocketAcceptor(); // LoggingFilter lf = new LoggingFilter("testLog"); Log4jFilter lf = new Log4jFilter(logger); acceptor.getFilterChain().addLast("logger", lf); acceptor.getFilterChain().addLast("codec", new ProtocolCodecFilter(new TextLineCodecFactory(Charset.forName("GBK")))); acceptor.setHandler(new TimeServerHandler()); acceptor.getSessionConfig().setReadBufferSize(10); acceptor.getSessionConfig().setIdleTime(IdleStatus.BOTH_IDLE, 10); acceptor.bind(new InetSocketAddress(PORT)); System.out.println("start server ..."); } } class TimeServerHandler extends IoHandlerAdapter { // static Logger logger = LoggerFactory.getLogger(TimeServerHandler.class); static Logger logger = Logger.getLogger(TimeServerHandler.class); @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(); if (str.trim().equalsIgnoreCase("quit")) { session.close(true); return; } logger.debug("Rec:" + str); Date date = new Date(); session.write(date.toString()); logger.debug("Message written..."); } @Override public void sessionIdle(IoSession session, IdleStatus status) throws Exception { logger.debug("IDLE " + session.getIdleCount(status)); } }

把配置文件按照自己的习惯放到conf目录下，就可以正常使用了。

需要注意的是，增加了自己的Log4jFilter之后，只能在您自己的代码中实现logger.debug()之类的调用时产生的日志记录才是正 常的，即按配置文件中的要求老老实实进行日志记录。对于Mina代码中用到的logger调用，因为还是用的默认的slf4j，找不到src目录下的 log4j.properties，所以产生的日志将无法正确显示和记录。除非您自己的将mina源代码中的logger全部改成log4j的 logger，这是个小小的遗憾，鱼和熊掌不能兼得呀。

下一篇中，我们将介绍，如何编写自己的编解码过滤器。