JBuilder2005+JBoss-4.0.2RC1+J2SDK1.5+Log4j 开发Session Bean例解（2）

先在JBuilder中建立工程，然后引入log4j库文件。 

新建工程：

选择菜单：new project…，name为Trader，点击finish。

这里工程目录为：E:\projects\Trader。 

拷贝类库：

在trader文件夹下新建lib文件夹，拷贝D:\logging-log4j-1.2.9\dist\lib\log4j-1.2.9.jar到E:\projects\Trader\lib下。 

将类库引入工程：

选择菜单：project〉project properties 〉Paths 〉右边Tab页Required Libraries > Add > Tab页Archives，选择E:\projects\Trader\lib，右边的列表框中选择log4j-1.2.9.jar，一路ok即可。 

新建web模块：

选择菜单：New 〉 Web 〉Web module（WAR）〉 OK按钮 〉Create Empty Web Module 〉 Next按钮，填入名称WebTrader，点击Finish按钮。 

增加properties配置文件：

在JBuilder左边的菜单树上选择WebTrader 〉Module Directory 〉选中WEB-INF 〉右键new 〉File，填入log4j.properties确定即可。

编辑log4j.properties的内容如下：

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log4j.properties

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# For the general syntax of property based configuration files see the

# documenation of org.apache.log4j.PropertyConfigurator. 

# The root category uses the appender called A1. Since no priority is

# specified, the root category assumes the default priority for root

# which is DEBUG in log4j. The root category is the only category that

# has a default priority. All other categories need not be assigned a

# priority in which case they inherit their priority from the

# hierarchy. 

log4j.rootCategory=, A1 

# A1 is set to be a FileAppender which outputs to the file

# "factor.log". Start the server NumberCruncherServer and two

# NumberCruncherClients, and ask to factor two numbers

# near-simultaneously. Notice that the log output from these two

# requests are logged in the file factor.log. Nevertheless, the logs

# of these requests can still be distinguished given their distinct

# nested diagnostic contexts. 

log4j.appender.A1=org.apache.log4j.FileAppender

log4j.appender.A1.File=${jboss.server.home.dir}/log/trader.log

log4j.appender.A1.layout=org.apache.log4j.PatternLayout 

# Note the %x conversion specifier for NDC printing.

# log4j.appender.A1.layout.ConversionPattern=%-4r %-5p [%t] (%x) - %m\n

log4j.appender.A1.layout.ConversionPattern=%d [%t] %-5p %c - %m%n

Log4j.appender.A1.MaxFileSize=100KB 

增加log4j环境初始化类：

右键点击菜单树中Trader.jpx 〉 New 〉Package，填入com.inspiresky.trader.init，确定即可。

右键点击新建的init包〉new 〉class，名字为Log4jInit.java，确定所在包为com.inspiresky.trader.init，点击OK键即可。

编辑Log4jInit.java的内容如下：

-----------------------------------------------------

Log4jInit.java

-----------------------------------------------------

package com.inspiresky.trader.init; 

import org.apache.log4j.PropertyConfigurator;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import java.io.PrintWriter;

import java.io.IOException;

import javax.servlet.ServletException; 

public class Log4jInit extends HttpServlet { 

    //Initialize global variables

    public void init() throws ServletException {

        String prefix =  getServletContext().getRealPath("/");

        String file = getInitParameter("log4j-init-file");

        // if the log4j-init-file is not set, then no point in trying

        if(file != null) {

            PropertyConfigurator.configure(prefix+file);

        }

    } 

    public void doGet(HttpServletRequest req, HttpServletResponse res) {

    } 

    //Clean up resources

    public void destroy() {

    }

} 

配置web.xml文件：

在JBuilder左边的菜单树上选择WebTrader 〉Module Directory 〉WEB-INF 下，打开web.xml，在<display-name>WebTrader</display-name>下增加如下内容：

<servlet>

    <servlet-name>log4j-init</servlet-name>

    <servlet-class>com.inspiresky.trader.init.Log4jInit</servlet-class>

    <init-param>

      <param-name>log4j-init-file</param-name>

      <param-value>WEB-INF/log4j.properties</param-value>

    </init-param>

    <load-on-startup>1</load-on-startup>

  </servlet> 

OK，至此我们的Log4j已经可以正常使用了。(