Question

我无法使用带有Spring MVC的Hibernate4将值插入数据库。它显示SessionFactory null pointer Exception。

我的代码：

package com.org.rahul.dao;

import org.hibernate.Session;
import org.hibernate.SessionFactory;

import org.springframework.beans.factory.annotation.Autowired;


import org.springframework.stereotype.Repository;

import com.org.rahul.dm.User;
@Repository
public class Registration {
@Autowired
private SessionFactory ses;
public User addMembers(User user){

Session se=ses.getCurrentSession();
se.persist(user);
String name=user.getName();
System.out.println(name);
return user;
}

}

异常堆栈跟踪：

Error
    Mar 09, 2015 10:24:45 AM org.apache.catalina.core.StandardWrapperValve     invoke
    SEVERE: Servlet.service() for servlet [spring-dispatcher] in context with    path [/SpringMvc] threw exception [Request processing failed; nested exception   is java.lang.NullPointerException] with root cause
    java.lang.NullPointerException
    at com.org.rahul.dao.Registration.addMembers(Registration.java:18)
    at com.org.rahul.GeneralController.registration(GeneralController.java:24)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at      sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at   sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.jav    a:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at     org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHa    ndlerMethod.java:219)
    at   org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(I    nvocableHandlerMethod.java:132)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
    at   org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapt    er.invokeHandleMethod(RequestMappingHandlerAdapter.java:745)
    at  org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapt    er.handleInternal(RequestMappingHandlerAdapter.java:686)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(A    bstractHandlerMethodAdapter.java:80)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.ja    va:856)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet    .java:936)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:83    8)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at   org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.    java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:2    22)
    at   org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:1    23)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.jav    a:472)
    at   org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118    )
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor    .java:1023)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
    at   java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at  java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)

弹簧调度-servlet.xml中

<bean id="myDataSource"
    class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"></property>
<property name="url" value="jdbc:mysql://localhost:3306/drift"></property>
<property name="username" value="root"></property>
<property name="password" value=""></property>
</bean>
<bean id="sessionFactory"     class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="myDataSource"></property>
<property name="packagesToScan" value="com.org.rahul.dm"></property>
<property name="hibernateProperties">
<props>
<prop key="dialect">org.hibernate.dialect.MySQLDialect</prop>
</props>
</property>
</bean>
<bean id="transactionManager"
class="org.springframework.orm.hibernate4.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory"></property>
</bean>

的web.xml

<servlet>
<servlet-name>spring-dispatcher</servlet-name>
<servlet-  class>org.springframework.web.servlet.DispatcherServlet</servlet-          class>
<load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
<servlet-name>spring-dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>

Answer 1

试试这个： -

@Repository
public class Registration {
    SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
    //Now get Session From SessionFactory instance indivdually for save, Update, delete Methods.
     public User addMembers(User user){
        Session session = sessionFactory.openSession();
        Transaction tx = session.beginTransaction();
        session.save(user);
        tx.commit(); // Must commit transaction if auto_commit  false in Hibernate.cfg.xml file.
        session.close();
        return user; 
     }

}

并检查cfg文件中的数据库连接参数。

带有Hibernate4的Spring MVC在SessionFactory中显示Null Pointer Exception

1 个答案: