我使用的是Oracle 11g R2数据库,我想对一张user表的id列自动生成主键,用的是序列,sql原始代码如下:
/* Oracle 11g 数据库脚本 */
CREATE TABLE t_user(
id NUMBER(10) PRIMARY KEY,
name VARCHAR(20)
);
/* 创建序列 */
CREATE SEQUENCE user_seq;
建立实体类
package nuc.sw.entity;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.SequenceGenerator;
import javax.persistence.Table;
@Entity
@Table(name="t_user")
@SequenceGenerator(sequenceName="user_seq",name="user_seq")
public class User {
private int id;
private String name;
@Id
@GeneratedValue(strategy=GenerationType.SEQUENCE,generator="user_seq")
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
接下来我写了一段这样的代码,目的是向数据库中插入一条记录(我整合了Spring4.2.4):
package nuc.sw.dao.impl;
import javax.annotation.Resource;
import org.springframework.orm.hibernate5.HibernateTemplate;
import org.springframework.stereotype.Component;
import nuc.sw.dao.UserDAO;
import nuc.sw.entity.User;
@Component("userDAOImpl")
public class UserDAOImpl implements UserDAO{
private HibernateTemplate hibernateTemplate;
public HibernateTemplate getHibernateTemplate() {
return hibernateTemplate;
}
@Resource
public void setHibernateTemplate(HibernateTemplate hibernateTemplate) {
this.hibernateTemplate = hibernateTemplate;
}
@Override
public void save(User user) throws Exception{
hibernateTemplate.save(user);
System.out.println("user "+user.getName()+" saved!");
}
}
package nuc.sw.service;
import javax.annotation.Resource;
import org.springframework.stereotype.Component;
import nuc.sw.dao.UserDAO;
import nuc.sw.dao.impl.UserDAOImpl;
import nuc.sw.entity.User;
@Component("userService")
public class UserService {
private UserDAO userDAO;
public UserDAO getUserDAO() {
return userDAO;
}
@Resource(name="userDAOImpl")
public void setUserDAO(UserDAO userDAO) {
this.userDAO = userDAO;
}
public void addUser(User user) throws Exception {
userDAO.save(user);
}
}
编写junit测试文件:
package nuc.sw.service;
import static org.junit.Assert.*;
import nuc.sw.entity.User;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class UserServiceTest {
@Test
public void testAddUser() throws Exception {
ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
UserService service = (UserService)ctx.getBean("userService");
User user = new User();
user.setName("张三");
service.addUser(user);
assertTrue(true);
}
}
Spring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:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-4.2.xsd
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.2.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-4.2.xsd">
<context:annotation-config/>
<context:component-scan base-package="nuc.sw"/>
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations">
<value>classpath:jdbc.properties</value>
</property>
</bean>
<bean id="dataSource" destroy-method="close"
class="org.apache.commons.dbcp2.BasicDataSource">
<property name="driverClassName" value="${jdbc.driverClassName}"/>
<property name="url" value="${jdbc.url}"/>
<property name="username" value="${jdbc.username}"/>
<property name="password" value="${jdbc.password}"/>
</bean>
<bean id="sessionFactory" class="org.springframework.orm.hibernate5.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="packagesToScan">
<list>
<value>nuc.sw.entity</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
org.hibernate.dialect.Oracle10gDialect
</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.format_sql">true</prop>
</props>
</property>
</bean>
<bean id="hibernateTemplete"
class="org.springframework.orm.hibernate5.HibernateTemplate">
<property name="sessionFactory" ref="sessionFactory"/>
</bean>
<bean id="txManager" class="org.springframework.orm.hibernate5.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory"/>
</bean>
<aop:config>
<aop:pointcut expression="execution(public * nuc.sw.service..*.*(..))"
id="businessService"/>
<aop:advisor advice-ref="txAdvice" pointcut-ref="businessService"/>
</aop:config>
<tx:advice id="txAdvice" transaction-manager="txManager">
<tx:attributes>
<tx:method name="add*" propagation="REQUIRED"/>
</tx:attributes>
</tx:advice>
</beans>
程序运行没有出现任何异常,但是结果id继1之后却是从-46开始插一条+1,真是奇怪了: