帮我看一下ssh 的一个空指针错误！

Question

impl：
public class UserDaoImpl  extends HibernateDaoSupport implements UserDao { public boolean isexist(String id) throws Exception {
boolean isexist=false;
String hql="from Employee where id=?";
Query q=super.getSession().createQuery(hql);
q.setString(0, id);
List list=q.list();
if(list.size()>0){
isexist=true;
}
return isexist;
} public boolean querylogin(String id, String name) throws Exception {
boolean isok=false;
String hql="from Employee where id=? and name=?";
Query q=super.getSession().createQuery(hql);
q.setString(0, id);
q.setString(1, name);
List list=q.list();
if(list.size()>0){
isok=true;
}
return isok;
}
action：public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
//ApplicationContext bf = new ClassPathXmlApplicationContext("applicationContext.xml");     LoginForm laf=(LoginForm) form;
  
     String Id =laf.getId();
     String Name=laf.getName();
     System.out.println(Id);
     System.out.println(Name);
   // UserDao dao = (UserDao)bf.getBean("userdaoimpl");  
     boolean is=userDao.querylogin(Id, Name);
    
      if(is=true) 
      {
       return mapping.findForward("success");   
      }   
      return null;   
}
spring 配置文件：
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="configLocation"
value="classpath:hibernate-cfg.xml">
</property>
</bean>
<bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">  
        <property name="sessionFactory">  
            <ref bean="sessionFactory"/>  
        </property>  
    </bean>  
    
    
   <!--   <bean id="hibernateTemplet"  
        class="org.springframework.orm.hibernate3.HibernateTemplate">  
        <property name="sessionFactory">  
            <ref bean="sessionFactory" />  
        </property>  
    </bean>  -->
          
     
     <bean id="userDao" class="fanfull.order.dao.impl.UserDaoImpl">  
        <property name="sessionFactory" ref="sessionFactory" />  
    </bean>  
    
    <bean name="/login" class="fanfull.order.actions.LoginAction" scope="prototype">  
    <property name="userDao" ref="userDao"/>  
</bean> 
    
   
   
    <tx:advice id="txAdvice" transaction-manager="transactionManager">  
        <tx:attributes>  
        <tx:method name="add*" propagation="REQUIRED"/>  
            <tx:method name="del*" propagation="REQUIRED"/>  
            <tx:method name="modify*" propagation="REQUIRED"/>  
            <tx:method name="register" propagation="REQUIRED"/>  
            <tx:method name="*" read-only="true"/>  
        </tx:attributes>  
    </tx:advice>  
       
    <aop:config>  
        <aop:pointcut id="allManagerMethod" expression="execution(* fanfull.order.manager.*.*.*(..))"/>  
        <aop:advisor advice-ref="txAdvice" pointcut-ref="allManagerMethod"/>  
    </aop:config>  
</beans>  web.xml <servlet>  
    <servlet-name>action</servlet-name>  
    <servlet-class>org.apache.struts.action.ActionServlet</servlet-class>  
    <init-param>  
      <param-name>config</param-name>  
      <param-value>/WEB-INF/struts-config.xml</param-value>  
    </init-param>  
    <init-param>  
      <param-name>debug</param-name>  
      <param-value>2</param-value>  
    </init-param>  
    <init-param>  
      <param-name>detail</param-name>  
      <param-value>2</param-value>  
    </init-param>  
    <load-on-startup>2</load-on-startup>  
  </servlet>  
       
  <!-- Standard Action Servlet Mapping -->  
  <servlet-mapping>  
    <servlet-name>action</servlet-name>  
    <url-pattern>*.do</url-pattern>  
  </servlet-mapping>  
       
    <context-param>  
    <param-name>contextConfigLocation</param-name>  
    <param-value>classpath:applicationContext.xml</param-value>  
    </context-param>  
    
    <listener>  
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>  
    </listener> 
       
    
<filter>  
        <filter-name>hibernateFilter</filter-name>  
        <filter-class>org.springframework.orm.hibernate3.support.OpenSessionInViewFilter</filter-class>  
      </filter>  
     <filter-mapping>  
        <filter-name>hibernateFilter</filter-name>  
        <url-pattern>/*</url-pattern>  
      </filter-mapping>    
     
       <filter>  
        <filter-name>Spring character encoding filter</filter-name>  
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>  
        <init-param>  
            <param-name>encoding</param-name>  
            <param-value>utf-8</param-value>  
        </init-param>  
      </filter>  
     <filter-mapping>  
        <filter-name>Spring character encoding filter</filter-name>  
        <url-pattern>/*</url-pattern>  
      </filter-mapping>  
      
      <filter>
    <filter-name>OpenSessionInViewFilter</filter-name>
    <filter-class>
        org.springframework.orm.hibernate3.support.OpenSessionInViewFilter
    </filter-class>
</filter>
      
  <welcome-file-list>  
    <welcome-file>index.jsp</welcome-file>  
  </welcome-file-list>  
</web-app>  
错误信息：严重: Servlet.service() for servlet action threw exception
java.lang.NullPointerException
at fanfull.order.actions.LoginAction.execute(LoginAction.java:45)
at org.apache.struts.chain.commands.servlet.ExecuteAction.execute(ExecuteAction.java:58)
at org.apache.struts.chain.commands.AbstractExecuteAction.execute(AbstractExecuteAction.java:67)
at org.apache.struts.chain.commands.ActionCommandBase.execute(ActionCommandBase.java:51)
at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:191)
at org.apache.commons.chain.generic.LookupCommand.execute(LookupCommand.java:305)
at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:191)
at org.apache.struts.chain.ComposableRequestProcessor.process(ComposableRequestProcessor.java:283)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913)
at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:462)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:75)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:75)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:619)

Answer 1

问题解决了 ，原来我在STRUTS 的配置文件中 的actions type属性中没用DelegatingActionProxy 进行spring 注入 login

Answer 2

用的struts1 
String hql="from Employee where id=?";
hql语句不能直接这样写吧  记得应该用别名的
String hql="from Employee emp where emp.id=?";