问题描述
- 学习用MyEclipse 2013开发SSH项目遇到java.lang.NullPointerException问题，请帮助！
-
SaveOfficeAction.java出错：java.lang.NullPointerExceptionpackage we.app.action; import we.app.data.*; import com.opensymphony.xwork2.ActionSupport; public class SaveOfficeAction extends ActionSupport { private IOffice B_Office; private IOfficeDAO B_OfficeDAO; private String Tips; public IOffice getB_Office() { return B_Office; } public void setB_Office(IOffice b_Office) { B_Office = b_Office; } public IOfficeDAO getB_OfficeDAO() { return B_OfficeDAO; } public void setB_OfficeDAO(IOfficeDAO b_OfficeDAO) { B_OfficeDAO = b_OfficeDAO; } public String getTips() { return Tips; } public void setTips(String tips) { Tips = tips; } public String execute() throws Exception { this.Tips=this.getB_OfficeDAO().findById(1).getOfficename().toString(); //this.Trans_OfficeDAO.save(this.B_Office); return SUCCESS; } }1、index.jsp：
<%@taglib uri="/struts-tags" prefix="s"%><%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>My JSP 'index.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <s:form action="SaveOffice"> <s:textfield name="B_Office.officename" label="officename"></s:textfield> <s:submit></s:submit> </s:form> <br> </body> </html>2、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="dialect">org.hibernate.dialect.SQLServerDialect</property> <property name="connection.url"> jdbc:jtds:sqlserver://192.168.0.100:4628/tnew </property> <property name="connection.username">sa</property> <property name="connection.password">111</property> <property name="connection.driver_class"> net.sourceforge.jtds.jdbc.Driver </property> <property name="myeclipse.connection.profile"> sqlserverjtds </property> <mapping resource="we/app/data/Peop.hbm.xml" /> <mapping resource="we/app/data/Office.hbm.xml" /> </session-factory> </hibernate-configuration>3、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" xmlns:p="http://www.springframework.org/schema/p" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.1.xsd" > <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"> <property name="configLocation" value="classpath:hibernate.cfg.xml"> </property> </bean> <bean id="PeopDAO" class="we.app.data.PeopDAO"> <property name="sessionFactory" ref="sessionFactory"></property> </bean> <bean id="B_OfficeDAO" class="we.app.data.OfficeDAO"> <property name="sessionFactory" ref="sessionFactory"></property> </bean> <bean id="B_Office" class="we.app.data.Office"></bean> <bean id="B_Peop" class="we.app.data.Peop"></bean> <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"> <property name="sessionFactory"> <ref bean="sessionFactory"/> </property> </bean> <bean id="Trans_OfficeDAO" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean"> <property name="transactionManager"> <ref bean="transactionManager" /> </property> <property name="target"> <ref local="B_OfficeDAO" /> </property> <property name="transactionAttributes"> <props> <prop key="*">PROPAGATION_REQUIRED</prop> </props> </property> </bean> </beans>4、
package we.app.data; import java.util.List; public interface IOfficeDAO { // property constants public static final String OFFICENAME = "officename"; public abstract void save(IOffice transientInstance); public abstract void delete(IOffice persistentInstance); public abstract IOffice findById(java.lang.Integer id); public abstract List findByExample(IOffice instance); public abstract List findByProperty(String propertyName, Object value); public abstract List findByOfficename(Object officename); public abstract List findAll(); public abstract IOffice merge(Office detachedInstance); public abstract void attachDirty(IOffice instance); public abstract void attachClean(IOffice instance); }
解决方案
你好歹把出错信息贴出来啊
解决方案二：
this.Tips=this.getB_OfficeDAO().findById(1).getOfficename().toString();中的B_officeDao是不是没有在你的action里面注入，也木有申明;要不你干脆new 一个B_officeDao在试试，要不你再你的Application.xml配置文件中加上一条
时间： 2024-10-31 21:15:38