新手提问，怎么使用JBoss?

使用JBoss和PostgreSQL-快速开发EJB和J2EE Web Application

先安装JSDK，再安装JBoss.
安装JSDK,必须获得一套对应于用户的操作系统的JDK，
我的安装的文件目录是
WINDOWS2000: d:\s1studio_jdk\j2sdk1.4.1
linux： /root/s1studio_jdk/j2sdk1.4.1
为了用EJB, 需要一个j2ee-1.3.jar或者j2ee-1.2.jar,
如果安装了Sun One Studio 或者 J2EE （www.sun.com ）这个文件已经有.
把这个文件放在classpath路径上.
或者使用jboss-j2ee.jar, 安装JBoss后在$JBoss\client中可找到.
建议安装Sun One Studio, 用Sun One Studio编译JAVA源程序,
不用设置classpath, 省去不少过程.

安装JBoss:
把JBoss的压缩包解开，放在任一目录上,
我的安装的文件目录是
/dose/jboss-3.0.4_tomcat-4.1.12 (REDHAT8.0)
E:\jboss-3.0.4_tomcat-4.1.12 (WINDOWS2000)
WINDOWS2000, linux共用同一套JBoss.

配置JBoss：
启动JBoss需要执行一个脚本文件：
linux：run.sh
WINDOWS对应的是：run.bat

(1)
在JBoss\bin\run.bat (for Windows)开头插入一行
set JAVA_HOME = d:\s1studio_jdk\j2sdk1.4.1
在JBoss\bin\run.sh (for Linux)开头插入一行
JAVA_HOME="/root/s1studio_jdk/j2sdk1.4.1"

或者
(2)设置系统环境变量JAVA_HOME,指向JDK

运行JBoss, run.sh或者run.bat
当看到启动JBoss的信息时，说明启动了.
服务器简单的测试：
JBoss默认的WEB端口为8080，我们可以在打开一个浏览器输入地址
http://localhost:8080/jmx-console
当在浏览器看到JBoss的信息时，说明安装配置JBoss成功了.

建立下面的目录和文件(注意大小写).

FIRST.EAR
|
|-----META-INF (application.xml)
|
|-----First.jar
| |-----META-INF (ejb-jar.xml,jboss.xml)
| `-----Dev
| |-----First(FirstSession.java, FirstSessionHome.java, FirstSessionBean.java)
| |-----Delegate(NewDelegate.java)
| `-----Dao(MysqlDao.java)
|
`-----First.war(index.jsp)
|
`-----WEB-INF (jboss-web.xml, web.xml)
|-----classes
`-----lib

/*
**
**MysqlDao.java
**
*/

package Dev.Dao;import java.sql.Connection;import java.sql.SQLException;import java.sql.Statement;import java.sql.ResultSet;import javax.naming.InitialContext;import javax.sql.DataSource;public class MysqlDao { public Connection getConnection() throws Exception { InitialContext ctx = new InitialContext(); DataSource ds = (DataSource) ctx.lookup("java:/PostgresDS"); Connection conn = null; Statement stmt = null; try { conn = ds.getConnection(); } catch (SQLException sqlEx) { System.out.println("Error connect to pool."); } return conn; } public String getName(String id) throws Exception { Connection conn = null; Statement stmt = null; ResultSet rs = null; String name = ""; try { conn = getConnection(); if ( conn !=null )System.out.println("Get conecttion. "+ conn.toString()); stmt = conn.createStatement(); if ( stmt !=null )System.out.println("Get Statement. "+ stmt.toString()); String sql = "SELECT * from users where id = ´"+id+"´"; System.out.println("Sql from getId(): "+sql); rs = stmt.executeQuery(sql); if ( rs !=null )System.out.println("Get result. "); if (rs.next()){ name = rs.getString("name"); } } catch (Exception sqlEx) { System.out.println("Error from getName()."); System.out.println("Error from DAO.getName() :" + sqlEx.getMessage()); }finally { if (conn != null) { try { conn.close(); } catch (Exception sqlEx) { } } } return name; } public String getCountry(String id) throws Exception { Connection conn = null; Statement stmt = null; String name = ""; try { conn = getConnection(); stmt = conn.createStatement(); String sql = "SELECT * from users where id = ´"+id+"´"; System.out.println("Sql from getCountry(): "+sql); java.sql.ResultSet rs = stmt.executeQuery(sql); if (rs.next()) { name = rs.getString("Country"); } } catch (SQLException sqlEx) { System.out.println("Error from getCountry()."); }finally { if (conn != null) { try { conn.close(); } catch (Exception sqlEx) { } } } return name; }}

/*
**
**NewDelegate.java
**
*/

package Dev.Delegate;import java.lang.*;import Dev.First.*;public class NewDelegate { Dev.First.FirstSession bean = null; public NewDelegate( ){ try { javax.naming.InitialContext ctx = new javax.naming.InitialContext(); Object objref = ctx.lookup("ejb/FirstSession"); Dev.First.FirstSessionHome testBean = (Dev.First.FirstSessionHome) javax.rmi.PortableRemoteObject.narrow (objref,Dev.First.FirstSessionHome.class); bean = testBean.create(); System.out.println("From JSP"); } catch (Exception NamingException) { NamingException.printStackTrace(); } } public String Welcome() { String msg = ""; try { msg = bean.Welcome(); } catch (Exception NamingException) { NamingException.printStackTrace(); } return msg; } public String getName(String id) { String name = ""; try { name = bean.getName(id); } catch (Exception NamingException) { NamingException.printStackTrace();} return name; } public String getCountry(String id) { String country = ""; try { country = bean.getCountry(id); } catch (Exception NamingException) { NamingException.printStackTrace();} return country; } }

/*
**
**FirstSession.java
**
*/

package Dev.First;import java.lang.*;import java.rmi.RemoteException;import javax.ejb.CreateException;import javax.ejb.EJBException;import javax.ejb.SessionBean;import javax.ejb.SessionContext;public interface FirstSession extends javax.ejb.EJBObject{ public String Welcome() throws java.rmi.RemoteException; public String getName(String id) throws java.rmi.RemoteException; public String getCountry(String id) throws java.rmi.RemoteException;}

/*
**
**FirstSessionHome.java
**
*/

package Dev.First;import java.lang.*;import java.rmi.RemoteException;import javax.ejb.CreateException;import javax.ejb.EJBException;import javax.ejb.SessionBean;import javax.ejb.SessionContext;public interface FirstSessionHome extends javax.ejb.EJBHome{public FirstSession create() throws javax.ejb.CreateException, java.rmi.RemoteException;}

/*
**
**FirstSessionBean.java
**
*/

package Dev.First;import java.rmi.RemoteException;import javax.ejb.CreateException;import javax.ejb.EJBException;import javax.ejb.SessionBean;import javax.ejb.SessionContext;public class FirstSessionBean implements SessionBean{public void ejbCreate() throws CreateException {}public String Welcome(){ String msg="Hello! This My Session Bean From Jboss."; System.out.println(msg); return msg;}public String getName(String id){ String name = ""; System.out.println("From bean before getName :"+ name); try{ Dev.Dao.MysqlDao dao = new Dev.Dao.MysqlDao(); name = dao.getName(id); System.out.println("From bean after getName :"+ name); }catch(Exception e){ System.out.println(e.getMessage());} return name;}public String getCountry(String id){ String country = ""; try{ Dev.Dao.MysqlDao dao = new Dev.Dao.MysqlDao(); country = dao.getCountry(id); }catch(Exception e){ } return country;}public void setSessionContext( SessionContext aContext ) throws EJBException {}public void ejbActivate() throws EJBException {}public void ejbPassivate() throws EJBException {}public void ejbRemove() throws EJBException {}}

/*Don´t put the following lines into index.jsp
**
**index.jsp
**
*/Don´t put the above lines into index.jsp

<%@page language="java" %><% String msg = ""; String msg1 = ""; Dev.Delegate.NewDelegate nn = new Dev.Delegate.NewDelegate(); if (request.getParameter("id") != null && request.getParameter("id") != ""&& !request.getParameter("id").equals("")){ String id = request.getParameter("id"); String name = ""; Dev.Dao.MysqlDao dao = new Dev.Dao.MysqlDao(); name = nn.getName(id); //access database through session bean //name = dao.getName(id); //access database directly if(name!= null && !name.equals("")){ msg1 ="Welcome " + name +" ! You are from "+ dao.getCountry(id)+ " ."; }else{ msg1 ="Please Check Your ID. : " + id; } } msg = nn.Welcome() ;%>
<%= msg %>

1.1、软件安装

起重要安装JDK（仅仅安装JRE是不可的，因为JSP页面须要编译），最新的正式版是JDK1.4.2。然后把JBoss的紧缩包解压到一个目次下，目次名通常为"Jboss_版本号"，JBoss今朝的最新正式版是JBoss4.0.0（2004年9月20日发布）。下面的设备都是针对JBoss3.2.5。

1.2、情况变量的设置

须要的情况变量有JAVA_HOME和JBOSS_HOME。情况变量JAVA_HOME设置为刚才JDK的安装路径，JBOSS_HOME设置为刚才JBoss解压后的路径。设置方法以下：

在Windows2000中可以右键点我的计算机，选"属性"－>选"高等"选项卡－>点击"情况变量"按钮－>点击体系变量的"新建"按钮，然后在对话框中输进"变量名"为"JAVA_HOME"，变量值为JDK的安装路径，最后断定。一样的方法添加JBOSS_HOME。

1.3、运行

直接履行JBoss\bin目次下的run.bat批处理文件便可，启动时光从20秒到1分钟阁下不等，视CPU速度和内存大年夜小而定。

1.4、终止JBoss的运行