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Question

哪位大哥帮我看看偶滴代码哪里出问题了呀UserActionpackage com.frank.action;
import java.util.List;
import com.frank.dao.UserDAo;
import com.frank.obj.User;
import com.opensymphony.xwork2.ActionSupport;
public class UserAction extends ActionSupport {
 private UserDAo userDao;
 private User user;
 private List users;
 private int userid;
 private int pageNo;
 private int pageCount;
 public int getPageNo() {
  return pageNo;
 }
 public void setPageNo(int pageNo) {
  this.pageNo = pageNo;
 }
 public void setUsers(List users) {
  this.users = users;
 }
 public int getUserid() {
  return userid;
 }
 public void setUserid(int userid) {
  this.userid = userid;
 }
 public User getUser() {
  return user;
 }
 public void setUser(User user) {
  this.user = user;
 }
 public String readyUpdate() throws Exception{
  user=this.getUserDao().getUserById(userid);
  if(user!=null){
   return SUCCESS;
  }
  return INPUT;
 }
 public String login() throws Exception{
  if(this.getUserDao().checkUser(user)){
   computePageCount();
   users=this.getUserDao().getAllUsers(pageNo);
   return SUCCESS;
  }
  return INPUT;
 }
 public String updateUser() throws Exception{
  if(this.getUserDao().updateUser(user)){
   computePageCount();
   users=this.getUserDao().getAllUsers(pageNo);
   return SUCCESS;
  }
  return INPUT;
 }
 public String deleteUser() throws Exception{
  User user=this.getUserDao().getUserById(userid);
  if(this.getUserDao().deleteUser(user)){
   computePageCount();
   users=this.getUserDao().getAllUsers(pageNo);
   return SUCCESS;
  }
  return INPUT;
 }
 public String insertUser() throws Exception{
  if(this.getUserDao().insertUser(user)){
   computePageCount();
   
   users=this.getUserDao().getAllUsers(pageNo);
   return SUCCESS;
  }
  return INPUT;
 }
 public String selectUser() throws Exception{
  computePageCount();
  users=this.getUserDao().getAllUsers(pageNo);
  return SUCCESS;
  
 }
 public void computePageCount(){
  int tempCount=this.getUserDao().getItemCount();
  pageCount=tempCount%10==0?tempCount/10:tempCount/10+1;  
 }
 @Override
 public String execute() throws Exception {
  // TODO Auto-generated method stub
  return super.execute();
 }
 public List getUsers() {
  return users;
 }
 public void setUsrs(List users) {
  this.users = users;
 }
 public int getPageCount() {
  return pageCount;
 }
 public void setPageCount(int pageCount) {
  this.pageCount = pageCount;
 }
public UserDAo getUserDao() {
return userDao;
}
public void setUserDao(UserDAo userDao) {
this.userDao = userDao;
} 
}

Answer 1

package com.frank.dao;
import org.hibernate.HibernateException;
import org.hibernate.Query;
import java.util.List;
import org.springframework.orm.hibernate3.HibernateTemplate;import com.frank.dao.UserDAo;
import com.frank.obj.User;
public class UserDAo{
 private HibernateTemplate hibernateTemplate;
 public HibernateTemplate getHibernateTemplate() {
  return hibernateTemplate;
 }
 public void setHibernateTemplate(HibernateTemplate hibernateTemplate) {
  this.hibernateTemplate = hibernateTemplate;
 }
 
 public boolean checkUser(User user){
 boolean checkUser = false;
 try{
   String queryString="from User user where user.username=? and user.password=?";
   List list=hibernateTemplate.find(queryString,new Object[]{user.getUsername(),user.getPassword()});
   if(list.size()>0){
    return true;
   }else{
    return false;
   }
  }catch(HibernateException ex){
   ex.printStackTrace();
   return false;
  }
 }
 public boolean updateUser(User user){
  try{
   hibernateTemplate.update(user);
   return true;
  }catch(HibernateException ex){
   ex.printStackTrace();
   return false;
  }
 }
 public boolean deleteUser(User user){
  try{
   hibernateTemplate.delete(user);
   return true;
  }catch(HibernateException ex){
   ex.printStackTrace();
   return false;
  }
 }
 public boolean insertUser(User user){
  try{
   hibernateTemplate.save(user);
   return true;
  }catch(HibernateException ex){
   ex.printStackTrace();
   return false;
  }
 }
 public User getUserById(int userid){
  try{
   User user=(User)hibernateTemplate.load(User.class, new Integer(userid));
   user.getUsername();
   return user;
  }catch(HibernateException ex){
   ex.printStackTrace();
   return null;
  }
 }
 public List getAllUsers(int pageNo){
  try{
   Query query=hibernateTemplate.getSessionFactory().openSession().createQuery("from User");
   query.setFirstResult(pageNo*10);
   query.setMaxResults(10);
   //String queryString="from Userinfo";
   //hibernateTemplate.setMaxResults(10);
   List list=query.list();
   return list;
  }catch(HibernateException ex){
   ex.printStackTrace();
   return null;
  }
 }
 public int getItemCount(){
  try{
   Query query=hibernateTemplate.getSessionFactory().openSession().createQuery("select count(*) from User user");
   Object obj=query.uniqueResult();
   int count=Integer.parseInt(obj.toString());
   return (int)count;
  }catch(HibernateException ex){
   ex.printStackTrace();
   return 0;
  }
 }
}

Answer 2

<?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:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="
    http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
    http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd
    http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">
 <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
  <property name="driverClassName">
   <value>com.mysql.jdbc.Driver</value>
  </property>
  <property name="url">
   <value>jdbc:mysql://localhost:3306/mydb</value>
  </property>
  <property name="username">
   <value>root</value>
  </property>
  <property name="password">
   <value>8625739</value>
  </property>
 </bean>
 <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
  <property name="dataSource">
   <ref bean="dataSource"/>
  </property>
  <property name="mappingResources">
   <list>
    <value>com/frank/obj/User.hbm.xml</value>
   </list>
  </property>
  <property name="hibernateProperties">
   <props>
    <prop key="hibernate.show_sql">true</prop>
    <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
   </props>
  </property>
 </bean>
 <bean id="hibernateTemplate" class="org.springframework.orm.hibernate3.HibernateTemplate">
  <property name="sessionFactory">
   <ref bean="sessionFactory"/>
  </property>
 </bean>
 <bean id="userDao" class="com.frank.dao.UserDAo">
  <property name="hibernateTemplate">
   <ref bean="hibernateTemplate"/>
  </property>
 </bean>
 <bean id="userAction" class="com.frank.action.UserAction">
 <property name="userDao">
 <ref bean="userDao"/> 
 </property>
 </bean>
 <bean id="txManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
  <property name="sessionFactory">
   <ref bean="sessionFactory"/>
  </property>
 </bean>
 <tx:advice id="myadvice" transaction-manager="txManager">
  <tx:attributes>
   <tx:method name="insert*" propagation="REQUIRED"/>
   <tx:method name="update*" propagation="REQUIRED"/>
   <tx:method name="delete*" propagation="REQUIRED"/>
   <tx:method name="*" propagation="SUPPORTS" read-only="true"/>
  </tx:attributes>
 </tx:advice>
 <aop:config>
  <aop:pointcut id="userPointcut" expression="execution(* com.frank.dao..*.*(..))"/>
  <aop:advisor advice-ref="myadvice" pointcut-ref="userPointcut"/>
 </aop:config>
</beans>

Answer 3

HTTP Status 500 - --------------------------------------------------------------------------------type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception java.lang.NullPointerException
com.frank.action.UserAction.login(UserAction.java:44)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
java.lang.reflect.Method.invoke(Method.java:597)
com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:440)
com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:279)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:163)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:249)
org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:148)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:93)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:128)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.interceptor.ProfilingActivationInterceptor.intercept(ProfilingActivationInterceptor.java:104)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:148)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:128)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)
org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:468)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:395)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.29 logs.
--------------------------------------------------------------------------------Apache Tomcat/6.0.29

Answer 4

java.lang.NullPointerException
com.frank.action.UserAction.login(UserAction.java:44)

Answer 5

 <bean id="userDao" class="com.frank.dao.UserDAo">
  <property name="hibernateTemplate">
  <ref bean="hibernateTemplate"/>
  </property>
 </bean>
 <bean id="userAction" class="com.frank.action.UserAction">
 <property name="userDao">
 <ref bean="userDao"/>  
 </property>检查拼写  ！！！我xxxx  我第一次这么有耐心看代码,.....我数44行 数了好几遍....

Answer 6

是的，我知道是空指针，但是我哪都查过了，不知道哪里有写错，不知道是不是spring引入的时候出错了

Answer 7

错了错了 是这个地方public void setUserDao(UserDAo userDao) {
this.userDao = userDao;应该是  setUserDAo吧

Answer 8

原来的项目中多了这个文件package com.frank.action;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.apache.struts2.ServletActionContext;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import com.frank.dao.RuleDAO;
import com.opensymphony.xwork2.ActionSupport;
public class BaseAction extends ActionSupport {
 public RuleDAO getRuleDAO(){
  ServletContext servletContext=ServletActionContext.getServletContext();
  WebApplicationContext webApplicationContext=WebApplicationContextUtils.getWebApplicationContext(servletContext);
  return (RuleDAO)webApplicationContext.getBean("ruleDAO");
 }
 public HttpServletRequest request(){
  return ServletActionContext.getRequest();
 }
 public HttpServletResponse response(){
  return ServletActionContext.getResponse();
 }
 public HttpSession session(){
  return ServletActionContext.getRequest().getSession();
 }
 public ServletContext application(){
  return ServletActionContext.getServletContext();
 }
} 

Answer 9

package com.frank.dao;
public class RuleDAO {
 private UserDAo userDAo;
 public UserDAo getUserDAo() {
  return userDAo;
 }
 public void setUserDAo(UserDAo userDAo) {
  this.userDAo = userDAo;
 }
 
}

Answer 10

com.frank.action.UserAction.login(UserAction.java:44)你贴的时候贴这里关键啊把这个方法贴出来看看就行了你贴这么多  晕啊

Answer 11

public String login() throws Exception{
  if(this.getUserDao().checkUser(user)){
  computePageCount();
  users=this.getUserDao().getAllUsers(pageNo);
  return SUCCESS;
  }
  return INPUT;
 }

Answer 12

问题解决了，哎其实没啥错。。就是项目缓存的问题我重启了Myeclipse后就运行成功了第一次发帖。。发的有点乱，罪过，罪过，再次谢谢帮助过我的叔叔阿姨们~~~^_^