jpa学习3-spring data jpa 入门环境搭建
1.新建java工程,导入jar包

•下载 SpringData Commons 和 SpringData JPA 两个发布包:
–Commons 是 SpringData 的基础包
–并把相关的依赖JAR文件加入到CLASSPATH中
结构图:
2.新建实体类
package com.zl.springdata.entity;
import java.util.Date;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
@Table(name="JPA_PERSONS")
@Entity
public class Person {
private Integer id;
private String lastName;
private String email;
private Date birth;
private Address address;
private Integer addressId;
@GeneratedValue
@Id
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public Date getBirth() {
return birth;
}
public void setBirth(Date birth) {
this.birth = birth;
}
@Column(name="ADD_ID")
public Integer getAddressId() {
return addressId;
}
public void setAddressId(Integer addressId) {
this.addressId = addressId;
}
@JoinColumn(name="ADDRESS_ID")
@ManyToOne
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
@Override
public String toString() {
return "Person [id=" + id + ", lastName=" + lastName + ", email="
+ email + ", brith=" + birth + "]";
}
}
2.db.properties:jdbc.user=root
jdbc.password=tiger
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc\:mysql\:///spring
3.applicationContext.xml配置:<jpa:repositories base-package="com.zl.springdata"
entity-manager-factory-ref="entityManagerFactory"></jpa:repositories>
entity-manager-factory-ref="entityManagerFactory"></jpa:repositories>
这个为配置spring data
<?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:tx="http://www.springframework.org/schema/tx"
xmlns:jpa="http://www.springframework.org/schema/data/jpa"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">
<!-- 配置自动扫描的包 -->
<context:component-scan base-package="com.zl.springdata"></context:component-scan>
<!-- 1. 配置数据源 -->
<context:property-placeholder location="classpath:db.properties"/>
<bean id="dataSource"
class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="user" value="${jdbc.user}"></property>
<property name="password" value="${jdbc.password}"></property>
<property name="driverClass" value="${jdbc.driverClass}"></property>
<property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
<!-- 配置其他属性 -->
</bean>
<!-- 2. 配置 JPA 的 EntityManagerFactory -->
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource"></property>
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"></bean>
</property>
<property name="packagesToScan" value="com.zl.springdata"></property>
<property name="jpaProperties">
<props>
<!-- 二级缓存相关 -->
<!--
<prop key="hibernate.cache.region.factory_class">org.hibernate.cache.ehcache.EhCacheRegionFactory</prop>
<prop key="net.sf.ehcache.configurationResourceName">ehcache-hibernate.xml</prop>
-->
<!-- 生成的数据表的列的映射策略 -->
<prop key="hibernate.ejb.naming_strategy">org.hibernate.cfg.ImprovedNamingStrategy</prop>
<!-- hibernate 基本属性 -->
<prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.format_sql">true</prop>
<prop key="hibernate.hbm2ddl.auto">update</prop>
</props>
</property>
</bean>
<!-- 3. 配置事务管理器 -->
<bean id="transactionManager"
class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory"></property>
</bean>
<!-- 4. 配置支持注解的事务 -->
<tx:annotation-driven transaction-manager="transactionManager"/>
<!-- 5. 配置 SpringData -->
<!-- 加入 jpa 的命名空间 -->
<!-- base-package: 扫描 Repository Bean 所在的 package -->
<jpa:repositories base-package="com.zl.springdata"
entity-manager-factory-ref="entityManagerFactory"></jpa:repositories>
</beans>
4.接口继承JpaRepository<实体类名,主键类型>下面是根据lastName查找数据
/**
* 1. Repository 是一个空接口. 即是一个标记接口
* 2. 若我们定义的接口继承了 Repository, 则该接口会被 IOC 容器识别为一个 Repository Bean.
* 纳入到 IOC 容器中. 进而可以在该接口中定义满足一定规范的方法.
*
* 3. 实际上, 也可以通过 @RepositoryDefinition 注解来替代继承 Repository 接口
*/
//@RepositoryDefinition(domainClass=Person.class,idClass=Integer.class)
public interface PersonRepsotory extends JpaRepository<Person, Integer>,JpaSpecificationExecutor<Person>{
//根据 lastName 来获取对应的 Person
Person getByLastName(String lastName);
}
5.调用:public void testHelloWorldSpringData() throws FileNotFoundException, IOException, InstantiationException, IllegalAccessException{
System.out.println(personRepsotory.getClass().getName());
Person person = personRepsotory.getByLastName("AA");
System.out.println(person);
}