SqlServer 2005 + SSH，执行hibernate的方法报 javalangNullPointerException 错

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问题： SqlServer 2005 + SSH，执行hibernate的方法报 javalangNullPointerException 错
描述:

JSP页面
<%@ page language="java" pageEncoding="UTF-8"%>
<%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html" %>

  
    
  
  
  
    
    
    
    
     用户名：
    
    
    
     密  码：
    
    
    
    
    
    
    
    
    
  

------------------------------------------------------------------
struts 配置文件
-------------------------------------------------------------------

  
  
      
  
  <>
      attribute="userInfoForm"
      input="/form/userInfo.jsp"
      name="userInfoForm"
      path="/login"
      scope="request"
      parameter="o"
      type="liupengpo.accountbook.action.UserInfoAction">
      
      
  
  
  

------------------------------------------------------------------------------------
spring 配置文件
------------------------------------------------------------------------------------

<>
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-2.5.xsd">
<>
class="org.apache.commons.dbcp.BasicDataSource">
<>
value="com.microsoft.sqlserver.jdbc.SQLServerDriver">

<>
value="jdbc:sqlserver://localhost:1433;databaseName=AccountBook">



<>
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">






org.hibernate.dialect.SQLServerDialect

true





liupengpo/accountbook/entity/Income.hbm.xml


liupengpo/accountbook/entity/Type.hbm.xml


liupengpo/accountbook/entity/UserInfo.hbm.xml





<>
class="liupengpo.accountbook.dao.impl.UserInfoDAOImpl">












---------------------------------------------------------------------
数据访问层
--------------------------------------------------------------------
package liupengpo.accountbook.dao.impl;
import java.util.List;
import liupengpo.accountbook.dao.UserInfoDAO;
import liupengpo.accountbook.entity.UserInfo;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
/**
 * 
 */
public class UserInfoDAOImpl extends HibernateDaoSupport implements UserInfoDAO {   
        public List findByName(Object name) {
return findByProperty(NAME, name);
}
}
------------------------------------------------------------------------------------
业务逻辑层
-------------------------------------------------------------------------------------
package liupengpo.accountbook.biz.impl;
import java.util.List;
import liupengpo.accountbook.biz.UserInfoBiz;
import liupengpo.accountbook.dao.UserInfoDAO;
import liupengpo.accountbook.entity.UserInfo;
public class UserInfoBizImpl implements UserInfoBiz {
         UserInfoDAO userInfoDAO = null;
         public boolean login(String name,String password) {
List list = userInfoDAO.findByName(name);
UserInfo userInfo = (UserInfo)list.get(0);
if (userInfo.getPassword().equals(password)) {
return true;
}else{
return false;
}
}
public UserInfoDAO getUserInfoDAO() {
return userInfoDAO;
}
public void setUserInfoDAO(UserInfoDAO userInfoDAO) {
this.userInfoDAO = userInfoDAO;
}
}
---------------------------------------------------------------------------------------
---------点击登录后错误如下  调试发现JSP页面中的用户名密码都已经得到--------- 
严重: Servlet.service() for servlet action threw exception
java.lang.NullPointerException at liupengpo.accountbook.action.UserInfoAction.doLogin(UserInfoAction.java:55)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.struts.actions.DispatchAction.dispatchMethod(DispatchAction.java:270)
at org.apache.struts.actions.DispatchAction.execute(DispatchAction.java:187)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
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.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:128)
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:286)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)

以上介绍了“ SqlServer 2005 + SSH，执行hibernate的方法报 javalangNullPointerException 错”的问题解答，希望对有需要的网友有所帮助。
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