搞了2天了`在线求答`````````(关于struts+hibernate+spring)配置文件

applicationContext.xml<?xml version="1.0" encoding="UTF-8"?>
<beans
xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd">
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="configLocation"
value="classpath:hibernate.cfg.xml">
</property>
</bean>

<bean name="/xx" class="com.struts.action.XxAction">
<property name="p" ref="person"></property>
<property name="b" ref="bo"></property>
</bean>

<bean id="person" class="com.jopo.Person"/>


<bean id="bo" class="com.Bo.Bo">
<property name="dao" ref="dao"></property>
</bean>

<bean id="dao" class="org.springframework.orm.hibernate3.support.HibernateDaoSupport">
<property name="sessionFactory" ref="sessionFactory"></property>
</bean>

</beans>
hibernate.cfg.xml<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
          "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
          "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"><!-- Generated by MyEclipse Hibernate Tools.                   -->
<hibernate-configuration><session-factory>
<property name="connection.username">root</property>
<property name="connection.url">
jdbc:mysql://localhost:3306/test
</property>
<property name="dialect">
org.hibernate.dialect.MySQLDialect
</property>
<property name="myeclipse.connection.profile">MySQL</property>
<property name="connection.driver_class">
com.mysql.jdbc.Driver
</property>
<property name="show_sql">true</property></session-factory></hibernate-configuration>
Action/*
 * Generated by MyEclipse Struts
 * Template path: templates/java/JavaClass.vtl
 */
package com.struts.action;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;import com.Bo.Bo;
import com.jopo.Person;
import com.struts.form.XxForm;/** 
 * MyEclipse Struts
 * Creation date: 03-16-2008
 * 
 * XDoclet definition:
 * @struts.action path="/xx" name="xxForm" input="/form/xx.jsp" scope="request" validate="true"
 */
public class XxAction extends Action {
/*
 * Generated Methods
 */
private Person p;
private Bo b;
/** 
 * Method execute
 * @param mapping
 * @param form
 * @param request
 * @param response
 * @return ActionForward
 */
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response) {
XxForm xxForm = (XxForm) form;// TODO Auto-generated method stub
// p.setName(xxForm.getName());
// p.setPassword(xxForm.getPassword());
b.execute(p);
return null;
}
public Bo getB() {
return b;
}
public void setB(Bo b) {
this.b = b;
}
public Person getP() {
return p;
}
public void setP(Person p) {
this.p = p;
}
}
为什么我一使用注释的代码就在浏览器出现如下错误：HTTP Status 500 - --------------------------------------------------------------------------------type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception javax.servlet.ServletException
org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:523)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1194)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause java.lang.NullPointerException
com.struts.action.XxAction.execute(XxAction.java:44)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:419)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1194)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.25 logs.
--------------------------------------------------------------------------------Apache Tomcat/5.5.25
log4j无任何错误！！！！！！！高手帮帮忙啊！