sprng mvc注解 service注入的有关问题 。

sprng mvc注解 service注入的问题 求救。。。
最近在学spring mvc ，为新项目做技术储备
折腾了一个星期，总算有点眉目了，今天下午写了个例子，用了三层结构 controller service 还有DAO，但是运行后发现service没有注入，导致项目的功能运行不正常，调了半天还是没有结果。。。各位大神帮忙看看
好了，废话不多说，上代码。。。。

先是controller

package com.itsum.springmvcpt.bg.test.controller;


import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import javax.validation.Valid;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.view.RedirectView;

import com.itsum.springmvcpt.bg.test.benas.dtos.User;
import com.itsum.springmvcpt.bg.test.services.Iservices.Iuserservice;
import com.itsum.springmvcpt.bg.test.services.serviceImpl.UserService;


@Controller
public class UserController {


private Iuserservice service;


public Iuserservice getService() {
return service;
}

public void setService(Iuserservice service) {
this.service = service;
}

@RequestMapping("/welcome")
public ModelAndView welcome(){
ModelAndView mv=new ModelAndView();
System.out.println("service:  "+service);
List<User> list=service.findByLimit(10);
mv.addObject("list", list);
mv.setViewName("welcome");
return mv;
}
}

然后是service接口:

package com.itsum.springmvcpt.bg.test.services.Iservices;

import java.util.List;

import com.itsum.springmvcpt.bg.test.benas.dtos.User;

public interface Iuserservice {

public List<User> findByLimit(int limit);

}

service实现:

package com.itsum.springmvcpt.bg.test.services.serviceImpl;

import java.util.List;

import javax.annotation.Resource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import com.itsum.springmvcpt.bg.test.benas.dtos.User;
import com.itsum.springmvcpt.bg.test.dao.Idaos.UserDao;
import com.itsum.springmvcpt.bg.test.services.Iservices.Iuserservice;


@Service("service")
public class UserService implements Iuserservice{


private UserDao dao;

public UserDao getDao() {
return dao;
}
public void setDao(UserDao dao) {
this.dao = dao;
}

@Transactional
public List<User> findByLimit(int limit){
return dao.findByLimit(limit);
}

}

DAO接口:

package com.itsum.springmvcpt.bg.test.dao.Idaos; 
 

import javax.annotation.Resource;

import org.mybatis.spring.SqlSessionTemplate;

public class SuperDao {
@Resource(name="sqlSession")
public SqlSessionTemplate template;
}

package com.itsum.springmvcpt.bg.test.dao.Idaos;

import java.util.List;

import org.springframework.stereotype.Component;

import com.itsum.springmvcpt.bg.test.benas.dtos.User;

 
public interface UserDao {
public List<User> findByLimit(int limit);

}

DAO实现:

package com.itsum.springmvcpt.bg.test.dao.daoImls;

import java.util.List;

import org.springframework.stereotype.Component;
import org.springframework.stereotype.Repository;

import com.itsum.springmvcpt.bg.test.benas.dtos.User;
import com.itsum.springmvcpt.bg.test.dao.Idaos.SuperDao;
import com.itsum.springmvcpt.bg.test.dao.Idaos.UserDao;



@Repository("dao") 
public class UserDaoImpl extends SuperDao implements UserDao {

@Override
public List<User> findByLimit(int limit) {
System.out.println("数据查询情况:  "+this.template.selectList("User.findByLimit", limit).size());
return this.template.selectList("User.findByLimit", limit);

}

}

接下来自然是配置文件了,
web.xml:

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>
springmvcpt</display-name>
<welcome-file-list>
<welcome-file>/welcome</welcome-file>
</welcome-file-list>

<servlet-mapping>  
    <servlet-name>default</servlet-name>  
    <url-pattern>*.jpg</url-pattern>
    <url-pattern>*.png</url-pattern>
    <url-pattern>*.gif</url-pattern>
    <url-pattern>*.css</url-pattern>
    <url-pattern>*.js</url-pattern>
    <url-pattern>*.swf</url-pattern>
    <url-pattern>*.pdf</url-pattern>
    <url-pattern>*.java</url-pattern>
    <url-pattern>*.class</url-pattern>
    <url-pattern>*.vm</url-pattern>
</servlet-mapping>


  <!-- spring mvc 的前置servlet -->
<servlet>  
    <servlet-name>springMVC</servlet-name>  
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  
    <load-on-startup>1</load-on-startup>  
</servlet>  
<servlet-mapping>  
    <servlet-name>springMVC</servlet-name>  
    <url-pattern>/</url-pattern>  
</servlet-mapping>  

  <!-- Spring Listener --> 
 
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath*:spring.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
</web-app>

spring-servlet.xml:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
 xmlns:context="http://www.springframework.org/schema/context"
 xmlns:p="http://www.springframework.org/schema/p"
 xmlns:mvc="http://www.springframework.org/schema/mvc"
 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-3.0.xsd
      http://www.springframework.org/schema/context
      http://www.springframework.org/schema/context/spring-context.xsd
      http://www.springframework.org/schema/mvc
      http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">
     
      <context:component-scan base-package="com.itsum.springmvcpt.bg"/>
      
      <mvc:annotation-driven />
      
     <!-- 对模型视图名称的解析，在请求时模型视图名称添加前后缀 -->
     <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
     <property name="viewClass" value="org.springframework.web.servlet.view.JstlView"/>
     <property name="prefix" value="/WEB-INF/jsp/"/>
    <property name="suffix" value=".jsp"/>
    
     </bean>
</beans>

mybaties的配置文件:

<?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:context="http://www.springframework.org/schema/context"
    xmlns:p="http://www.springframework.org/schema/p" 
    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-3.0.xsd
http://www.springframework.org/schema/context 
http://www.springframework.org/schema/context/spring-context-3.0.xsd 
http://www.springframework.org/schema/aop 
http://www.springframework.org/schema/aop/spring-aop-3.0.xsd 
http://www.springframework.org/schema/tx 
    http://www.springframework.org/schema/tx/spring-tx-3.0.xsd"
>
<tx:annotation-driven transaction-manager="transactionManager"/>
<context:annotation-config></context:annotation-config>
<context:component-scan base-package="com.itsum.springmvcpt.bg"/>

<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="configLocation" value="classpath:mybatis.xml"/>
</bean> 
 

<bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
<constructor-arg index="0" ref="sqlSessionFactory" />
</bean>

<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource" />
</bean>

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>

<property name="url" value="jdbc:mysql://127.0.0.1:3306/test"/> 
<property name="username" value="root"/>
<property name="password" value="root"/>
<property name="maxWait"            value="1000" />
        <property name="initialSize"        value="5" />
        <property name="maxActive"          value="20" />
        <property name="maxIdle"            value="5" />
        <property name="testWhileIdle"      value="true" />
        <property name="timeBetweenEvictionRunsMillis"  value="15000" />
        <property name="numTestsPerEvictionRun"         value="20" />
        <property name="validationQuery"    value="SELECT 1 FROM DUAL" />
        <property name="removeAbandoned"    value="true" />
        <property name="removeAbandonedTimeout"         value="180" />

 <!-- 
<property name="url" value="jdbc:mysql://localhost:3306/demo"/>
<property name="username" value="root"/>
<property name="password" value="ushuaia"/>
<property name="initialSize" value="5"/>
<property name="maxActive" value="50"/>
<property name="maxIdle" value="10"/>
<property name="maxWait" value="20"/>
<property name="minIdle" value="1"/>
 -->
</bean>
</beans>

MVC Java spring?mvc 注解 mybaties
[解决办法]
你仔细看看UserController，private Iuserservice service;没加注解  肯定空指针了

UserService也是  里面的userdao也没加注解
[解决办法]
首先给你一个案例DEMO

@Service
public class MovieFinder {
// ...
}

public class SimpleMovieLister {
    
private MovieFinder movieFinder;
    @Autowired
    public void setMovieFinder(MovieFinder movieFinder) { 
 
this.movieFinder = movieFinder;
    }
}

或者直接绑定到变量上，不用提供setter方法
@Autowired
private MovieFinder movieFinder;

service注解的参数name是用来表明bean的名称的
比如
@Service("myService")
public class BizService {

}

如果要自动装配这个bean，可以使用
@Service("myService")
private BizService bizService 
[解决办法]
contorller跟service里面各自引用的private Iuserservice service和private UserDao dao，必须用@Resource(name="service")，@Resource(name="dao")注解，才能实例化！

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