Question

我是Spring MVC和Hibernate的新手，我的会话配置有问题。我通过使用hibernate完成了这个。我现在要做的是sessionFactory将在DAO中自动装配。

这是application-context.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:mvc="http://www.springframework.org/schema/mvc" xmlns:beans="http://www.springframework.org/schema/beans"
      xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
      xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd">

      <!-- Enable @Controller annotation support -->
      <mvc:annotation-driven />
     <mvc:default-servlet-handler/>
      <!-- Map simple view name such as "test" into /WEB-INF/test.jsp -->
      <beans:bean   class="org.springframework.web.servlet.view.InternalResourceViewResolver">      
            <beans:property name="prefix" value="/jsp" />       
            <beans:property name="suffix" value=".jsp" />   
      </beans:bean>

      <!-- Scan classpath for annotations (eg: @Service, @Repository etc) -->
      <context:component-scan base-package="com.nutsaboutcandywebproject.controller"/>

      <!-- JDBC Data Source. It is assumed you have MySQL running on localhost port 3306 with 
           username root and blank password. Change below if it's not the case -->
      <bean id="myDataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/db_nutsaboutcandy"/>
        <property name="username" value="root"/>
        <property name="password" value=""/>
        <property name="validationQuery" value="SELECT 1"/>
      </bean>

      <!-- Hibernate Session Factory -->
      <bean id="mySessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
        <property name="dataSource" ref="myDataSource"/>
        <property name="packagesToScan">
           <list>
                <value>com.nutsaboutcandywebproject.model</value>
            </list>
        </property>
        <property name="hibernateProperties">
          <value>   
            hibernate.dialect=org.hibernate.dialect.MySQLDialect
          </value>
        </property>
      </bean>

        <!-- Hibernate Transaction Manager -->
      <bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory" ref="mySessionFactory"/>
      </bean> 

      <!-- Activates annotation based transaction management -->
      <tx:annotation-driven transaction-manager="transactionManager"/> 

    </beans>

这是完整的堆栈跟踪。

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'shoppingCartController' defined in file [C:\Users\Jeremy Marvin\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\NutsAboutCandyWebProject\WEB-INF\classes\com\nutsaboutcandywebproject\controller\ShoppingCartController.class]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [com.nutsaboutcandywebproject.controller.ShoppingCartController]: Constructor threw exception; nested exception is java.lang.NullPointerException
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1076)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1021)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:700)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:658)
    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:624)
    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:672)
    at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:543)
    at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:484)
    at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
    at javax.servlet.GenericServlet.init(GenericServlet.java:158)
    at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1279)
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1192)
    at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:864)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:134)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [com.nutsaboutcandywebproject.controller.ShoppingCartController]: Constructor threw exception; nested exception is java.lang.NullPointerException
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:164)
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:89)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1069)
    ... 34 more
Caused by: java.lang.NullPointerException
    at com.nutsaboutcandywebproject.dao.SQLProductsDataAccess.getCurrentSession(SQLProductsDataAccess.java:24)
    at com.nutsaboutcandywebproject.dao.SQLProductsDataAccess.getInventory(SQLProductsDataAccess.java:35)
    at com.nutsaboutcandywebproject.service.ServiceFacadeImpl.getAllProducts(ServiceFacadeImpl.java:140)
    at com.nutsaboutcandywebproject.controller.ShoppingCartController.<init>(ShoppingCartController.java:35)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:148)
    ... 36 more

Apr 04, 2014 1:30:44 AM org.apache.catalina.core.ApplicationContext log
SEVERE: StandardWrapper.Throwable
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'shoppingCartController' defined in file [C:\Users\Jeremy Marvin\workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\NutsAboutCandyWebProject\WEB-INF\classes\com\nutsaboutcandywebproject\controller\ShoppingCartController.class]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [com.nutsaboutcandywebproject.controller.ShoppingCartController]: Constructor threw exception; nested exception is java.lang.NullPointerException
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1076)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1021)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:700)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:658)
    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:624)
    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:672)
    at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:543)
    at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:484)
    at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
    at javax.servlet.GenericServlet.init(GenericServlet.java:158)
    at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1279)
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1192)
    at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:864)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:134)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [com.nutsaboutcandywebproject.controller.ShoppingCartController]: Constructor threw exception; nested exception is java.lang.NullPointerException
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:164)
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:89)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1069)
    ... 34 more
Caused by: java.lang.NullPointerException
    at com.nutsaboutcandywebproject.dao.SQLProductsDataAccess.getCurrentSession(SQLProductsDataAccess.java:24)
    at com.nutsaboutcandywebproject.dao.SQLProductsDataAccess.getInventory(SQLProductsDataAccess.java:35)
    at com.nutsaboutcandywebproject.service.ServiceFacadeImpl.getAllProducts(ServiceFacadeImpl.java:140)
    at com.nutsaboutcandywebproject.controller.ShoppingCartController.<init>(ShoppingCartController.java:35)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:148)
    ... 36 more

Apr 04, 2014 1:30:44 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Allocate exception for servlet appServlet
java.lang.NullPointerException
    at com.nutsaboutcandywebproject.dao.SQLProductsDataAccess.getCurrentSession(SQLProductsDataAccess.java:24)
    at com.nutsaboutcandywebproject.dao.SQLProductsDataAccess.getInventory(SQLProductsDataAccess.java:35)
    at com.nutsaboutcandywebproject.service.ServiceFacadeImpl.getAllProducts(ServiceFacadeImpl.java:140)
    at com.nutsaboutcandywebproject.controller.ShoppingCartController.<init>(ShoppingCartController.java:35)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:148)
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:89)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1069)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1021)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:700)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:658)
    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:624)
    at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:672)
    at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:543)
    at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:484)
    at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
    at javax.servlet.GenericServlet.init(GenericServlet.java:158)
    at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1279)
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1192)
    at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:864)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:134)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:170)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1040)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:313)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

这是DAO的代码

package com.nutsaboutcandywebproject.dao;

import java.util.List;

import javax.transaction.Transactional;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.springframework.beans.factory.annotation.Autowired;

import com.nutsaboutcandywebproject.model.Category;
import com.nutsaboutcandywebproject.model.Inventory;
import com.nutsaboutcandywebproject.model.Product;
import com.nutsaboutcandywebproject.model.ProductTypes;

public class SQLProductsDataAccess implements IProductsDataAccess {

    @Autowired
    SessionFactory sessionFactory;

     protected Session getCurrentSession(){
         return sessionFactory.getCurrentSession();
     }


    public Inventory getInventory()
    {

        Session session = getCurrentSession();
        Transaction transaction = session.beginTransaction();

        String sqlQuery = "from Product";
        Query query = session.createQuery(sqlQuery);
        System.out.println("Query created...");

        @SuppressWarnings("unchecked")
        List<Product> productsList = (List<Product>) query.list();

        Inventory inventory = new Inventory();
        inventory.setProducts(productsList);

        transaction.commit();

        session.close();
        return inventory;
    }

    public Product getProductById(Integer id) {

        Session session = getCurrentSession();
        Transaction transaction = session.beginTransaction();

        Query hqlQuery = session.createQuery("from Product WHERE id = :id");

        hqlQuery.setParameter("id", id);

        System.out.println("Query created...");

        List<?> productList = hqlQuery.list();
        Product product = (Product) productList.get(0);

        transaction.commit();

        session.close();

        return product;     

    }


    public List<Category> getCategoryName()
    {

        Session session = getCurrentSession();
        Transaction transaction = session.beginTransaction();

        String sqlQuery = "from Category";
        Query query = session.createQuery(sqlQuery);
        System.out.println("Query created...");

        List<Category> categoryList = query.list();

        transaction.commit();

        session.close();
        return categoryList;

    }


    @Override
    public Integer addStock(Integer id)
    {


        Product product = getProductById(id);

        int quantity = product.getQuantityInStock() + 1000;

        Session session = getCurrentSession();
        Transaction transaction = session.beginTransaction();

        String sqlQuery = "UPDATE Product set quantityInStock = :quantity"
                + " where id = :id";
        Query query = session.createQuery(sqlQuery);
        query.setParameter("quantity", quantity);
        query.setParameter("id", id);

        query.executeUpdate();

        transaction.commit();

        session.close();
        return quantity;

    }


    @Override
    public List<ProductTypes> getTypeName() {

        Session session = getCurrentSession();
        Transaction transaction = session.beginTransaction();

        String sqlQuery = "from ProductTypes";
        Query query = session.createQuery(sqlQuery);
        System.out.println("Query created...");

        List<ProductTypes> typeList = query.list();

        transaction.commit();

        session.close();
        return typeList;
    }


    @Override
    public void updateProduct(Integer updatedQuantity, Integer productId) {


        Session session = getCurrentSession();
        Transaction transaction = session.beginTransaction();

        String sqlQuery = "UPDATE Product set quantityInStock = :quantity"
                + " where id = :id";
        Query query = session.createQuery(sqlQuery);
        query.setParameter("quantity", updatedQuantity);
        query.setParameter("id", productId);
        System.out.println("Query created...");

        query.executeUpdate();

        transaction.commit();

        session.close();

    }


    @Override
    public Integer deleteProduct(Integer productId)
    {

        Session session = getCurrentSession();
        Transaction transaction = session.beginTransaction();
        Query query = session.createQuery("delete Product where id = :id");

        query.setParameter("id",productId);
        int result = query.executeUpdate();

        transaction.commit();

        session.close();

        return result;
    }



}

ShoppingCartController

package com.nutsaboutcandywebproject.controller;



@SessionAttributes(value = {"customerSession","cartSession"})
@Controller
public class ShoppingCartController {

    private ServiceFacade facade = new ServiceFacadeImpl();
    private NACExceptions exceptionsNAC = new NACExceptions();
    private List<Product> productsList = facade.getAllProducts();
    private List<Category> categoryList = facade.getCategory();
    private List<ProductTypes> typeList = facade.getType();
    private List<Sizes> sizeList = facade.getAllSizes();
    private List<ProductPriceMatrix> priceMatrixList = facade.getProductPriceMatrices();
    private List<String> exceptionList = new ArrayList<String>();

    @RequestMapping(value = "/cart", method = RequestMethod.POST)
      public String doShop(Model model, @RequestParam("smallSize") String[] small,
              @RequestParam("mediumSize") String[] medium ,@RequestParam("largeSize") String[] large) 
      {
        ServletRequestAttributes attr = (ServletRequestAttributes) RequestContextHolder.currentRequestAttributes();
        HttpSession session = attr.getRequest().getSession();

        List<ShoppingCart> cartList  = new ArrayList<ShoppingCart>();
        boolean isCartEmpty = true;

        if(session.getAttribute("cartSession")!=null){
            cartList = (List<ShoppingCart>) session.getAttribute("cartSession");
            isCartEmpty = false;
        }

        for(int index=0; index<productsList.size();index++){

            int numberOfSmall = 0;
            int numberOfMedium = 0;
            int numberOfLarge = 0;

            Integer productId = productsList.get(index).getId();

            Sizes size = priceMatrixList.get(index).getSize();
            Product product = facade.getSingleProduct(productId);


            try{
                exceptionsNAC.numberCheck(small[index]);
                exceptionsNAC.numberCheck(medium[index]);
                exceptionsNAC.numberCheck(large[index]);

                exceptionsNAC.checkValues(small[index]);
                exceptionsNAC.checkValues(medium[index]);
                exceptionsNAC.checkValues(large[index]);

                numberOfSmall = Integer.parseInt(small[index]);
                numberOfMedium = Integer.parseInt(medium[index]);
                numberOfLarge = Integer.parseInt(large[index]);

            }catch(ProductException e){
                exceptionList.add(e.getMessage());
            }


            User user = (User) session.getAttribute(("customerSession"));



            if(small[index] != null && numberOfSmall!=0){

                try {
                    if(exceptionsNAC.getRemainingQuantityInStock(50,numberOfSmall,product.getId())){            

                        ShoppingCart cart = new ShoppingCart(0,user,product,size,numberOfSmall);

                        cartList.add(cart);
                    }
                } catch (ProductException e) {
                    exceptionList.add(e.getMessage());
                }

            }

            if(medium[index] != null && numberOfMedium!=0){

                try {
                    if(exceptionsNAC.getRemainingQuantityInStock(100,numberOfMedium,product.getId())){

                        ShoppingCart cart = new ShoppingCart(0,user,product,size,numberOfMedium);

                        cartList.add(cart);
                    }
                } catch (ProductException e) {
                    exceptionList.add(e.getMessage());
                }


            }


            if(large[index] != null && numberOfLarge!=0){

                try {
                    if(exceptionsNAC.getRemainingQuantityInStock(150,numberOfLarge,product.getId())){
                        ShoppingCart cart = new ShoppingCart(0,user,product,size,numberOfLarge);

                        cartList.add(cart);
                    }
                } catch (ProductException e) {
                    exceptionList.add(e.getMessage());
                }

            }

        }

        if(isCartEmpty){
            session.setAttribute("cartSession", cartList);
        }

        model.addAttribute("cartSession", cartList);
        model.addAttribute("productsList", productsList);
        model.addAttribute("categoryList", categoryList);
        model.addAttribute("typeList", typeList);
        model.addAttribute("sizeList", sizeList);
        model.addAttribute("priceMatrixList", priceMatrixList);
        model.addAttribute("exception", exceptionList);

        return "/ShoppingCart";
     }




}

Answer 1

您在组件扫描配置中缺少“dao”包：

<context:component-scan base-package="com.nutsaboutcandywebproject.controller"/>
<context:component-scan base-package="com.nutsaboutcandywebproject.dao"/>

此外，DAO类必须具有@Repository注释才能将其用作自动装配组件。

Answer 2

你的DAO和服务对象需要是Spring控件下的bean。通过像这样实例化它们：

private ServiceFacade facade = new ServiceFacadeImpl();

Spring永远不会注入您的依赖项并将所有内容连接起来，因此NPE。将以下内容添加到XML文件

<context:component-scan base-package="com.nutsaboutcandywebproject.dao"/>
<context:component-scan base-package="com.nutsaboutcandywebproject.service"/>

并确保您的DAO标记为@Repository或@Component，并将您的服务标记为@Service或@Component。并将facade的实例化更改为

@Autowired
private ServiceFacade facade;

由于没有扫描DAO包，您几乎肯定必须在ServiceFacadeImpl及其IProductsDataAccess字段中执行相同操作。

更新：除此之外，您还要访问尚未初始化的bean，例如

private List<Product> productsList = facade.getAllProducts();

在那个时间点，即在对象实例化期间，Spring还没有完成你的DAO，Hibernate会话工厂等的创建。当Spring完成初始化和注入依赖项时，你只能访问这些bean并设置你的字段。。为此，请将代码放在标有@PostConstruct的初始化方法中：

@Controller
public class ShoppingCartController {

    @Autowired
    private ServiceFacade facade;;
    private NACExceptions exceptionsNAC = new NACExceptions();
    private List<Product> productsList;
    private List<Category> categoryList;
    private List<ProductTypes> typeList;
    private List<Sizes> sizeList;
    private List<ProductPriceMatrix> priceMatrixList;
    private List<String> exceptionList = new ArrayList<String>();

    @PostConstruct
    public void someInitializationMethod() {

        productsList = facade.getAllProducts();
        categoryList = facade.getCategory();
        typeList = facade.getType();
        sizeList = facade.getAllSizes();
        priceMatrixList = facade.getProductPriceMatrices();
    }
       ....

Answer 3

添加更多这样的行 - 以便启动bean和数据源

<bean id="shoppingCartController" class="point.it.to.implementation.class">
    <property name="mySessionFactory" ref="mySessionFactory"/>
</bean>

您甚至可以尝试使用@Autowired注释，通过简化为其创建setter方法。

Spring和Hibernate中的Session Factory

3 个答案: