spring调整hibernate的时候主键生成策略无法自动生成id

spring整合hibernate的时候主键生成策略无法自动生成id

package info.bishe.model;


import javax.persistence.Entity;

import javax.persistence.GeneratedValue;


import javax.persistence.Id;


@Entity

public class User {

	private int id;

	private String username;

	private  String password;

	@Id

	@GeneratedValue //无法生成自动增长的主键

	public int getId() {

		return id;

	}


	public void setId(int id) {

		this.id = id;

	}


	public String getUsername() {

		return username;

	}


	public void setUsername(String username) {

		this.username = username;

	}


	public String getPassword() {

		return password;

	}


	public void setPassword(String password) {

		this.password = password;

	}


}

package info.bishe.dao;


import info.bishe.model.User;


public interface UserDAO {

	public void save(User u);

}

package info.bishe.dao.imp;


import info.bishe.dao.UserDAO;

import info.bishe.model.User;



import javax.annotation.Resource;



import org.hibernate.SessionFactory;

import org.hibernate.classic.Session;

import org.springframework.stereotype.Component;

@Component("userDAO")//可以指定名称

public class UserDAOimp implements UserDAO {

	private SessionFactory sessionFactory;


	public SessionFactory getSessionFactory() {

		return sessionFactory;

	}

	@Resource

	public void setSessionFactory(SessionFactory sessionFactory) {

		this.sessionFactory = sessionFactory;

	}


	public void save(User user) {

			Session session = sessionFactory.openSession();

			session.beginTransaction();

			session.save(user);

			session.getTransaction().commit();

			session.close();


	}


}

package info.bishe.Service;

import javax.annotation.PostConstruct;

import javax.annotation.PreDestroy;

import javax.annotation.Resource;


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

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

import org.springframework.stereotype.Component;


import com.sun.xml.internal.ws.api.PropertySet.Property;


import info.bishe.dao.UserDAO;

import info.bishe.dao.imp.UserDAOimp;

import info.bishe.model.User;


@Component("userService")

public class UserService {


	private UserDAO userDAO;

	@PostConstruct

	public void init(){

		System.out.println("init");

	}



	public UserDAO getUserDAO() {

		return userDAO;

	}

	//@Autowired

	@Resource(name="userDAO")

	public void setUserDAO(UserDAO userDAO) {

		this.userDAO = userDAO;

	}

	public void add(User user){

		this.userDAO.save(user);

	}

	@PreDestroy

	public void destroy(){

		System.out.println("destroy");

	}

}

spring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"

       xsi:schemaLocation="http://www.springframework.org/schema/beans

           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd

           http://www.springframework.org/schema/context

           http://www.springframework.org/schema/context/spring-context-2.5.xsd">

<context:annotation-config/>

<context:component-scan base-package="info.bishe"/>

	<bean id="dataSource" 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/test?useUnicode=true&amp;characterEncoding=UTF-8"/>

    	<property name="username" value="root"/>

    	<property name="password" value="baojie123"/>

  	</bean>


  	<bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">

    	<property name="dataSource" ref="dataSource"/>

    	<property name="annotatedClasses">

      		<list>

        		<value>info.bishe.model.User</value>

      		</list>