三 Spring Data-Spring整合hibernate基於JPA規範

本Spring Data系列的內容均是根據 百戰程序員關於Sping Data視頻 編寫而成。

JPA：由sun公司提供的一套對於持久層操作的標準（接口+文檔）

Hibernate：是Gavin King開發的一套對於持久層操作的自動的ORM框架。

Hibernate JPA：是在hibernate3.2版本提供了對於JPA的標準的實現，提供了一套按照JPA標準實現持久層開發的API。

一 hibernate-jpa環境搭建

1.1 創建maven項目（02-spring-data-hibernate-jpa）

1.2 修改pom.xml文件

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>com.bjsxt</groupId>
	<artifactId>02-spring-data-hibernate-jpa</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<properties>
		<java.version>1.8</java.version>
		<spring.version>4.3.23.RELEASE</spring.version>
		<hibernate.version>5.1.17.Final</hibernate.version>
		<mysql.version>5.1.47</mysql.version>
		<c3p0.version>0.9.2.1</c3p0.version>
		<junit.version>4.12</junit.version>
		<lombok.version>1.18.6</lombok.version>
		<hibernate-entitymanager.version>5.0.7.Final</hibernate-entitymanager.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-core</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-context</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-aspects</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-aop</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-jdbc</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-orm</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-test</artifactId>
			<version>${spring.version}</version>
		</dependency>

		<dependency>
			<groupId>org.hibernate</groupId>
			<artifactId>hibernate-core</artifactId>
			<version>${hibernate.version}</version>
		</dependency>

		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>${mysql.version}</version>
		</dependency>

		<dependency>
			<groupId>com.mchange</groupId>
			<artifactId>c3p0</artifactId>
			<version>${c3p0.version}</version>
		</dependency>

		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>${junit.version}</version>
			<scope>test</scope>
		</dependency>

		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
			<version>${lombok.version}</version>
			<scope>provided</scope>
		</dependency>
		
		<dependency>
			<groupId>org.hibernate</groupId>
			<artifactId>hibernate-entitymanager</artifactId>
			<version>${hibernate-entitymanager.version}</version>
		</dependency>

	</dependencies>
</project>

1.3 添加jdbc.properties

jdbc.url=jdbc:mysql://localhost:3306/spring-data-test?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT
#jdbc.url=jdbc:mysql://localhost:3306/spring-data-test 這個保存到數據庫中會導致亂碼
jdbc.driver.class=com.mysql.jdbc.Driver
jdbc.username=root
jdbc.password=123456

1.4 添加applicationContext.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:aop="http://www.springframework.org/schema/aop"
	xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.3.xsd
		http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">

	<!-- 配置讀取properties文件的工具類 -->
	<context:property-placeholder location="classpath:jdbc.properties" />

	<!-- 配置c3p0數據庫連接池 -->
	<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
		<property name="jdbcUrl" value="${jdbc.url}" />
		<property name="driverClass" value="${jdbc.driver.class}" />
		<property name="user" value="${jdbc.username}" />
		<property name="password" value="${jdbc.password}" />
	</bean>

	<!-- spring整合jpa 配置EntityManagerFactory -->
	<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
		<property name="dataSource" ref="dataSource" />
		<property name="jpaVendorAdapter">
			<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
				<!-- hibernate相關的屬性注入 -->
				<!-- 配置數據庫類型 -->
				<property name="database" value="MYSQL" />
				<!-- 正向工程自動創建表 -->
				<property name="generateDdl" value="true" />
				<!-- 顯示執行的sql -->
				<property name="showSql" value="true" />
			</bean>
		</property>
		
		<!-- 配置掃描實體的包 -->
		<property name="packagesToScan">
			<list>
				<value>com.bjsxt.pojo</value>
			</list>
		</property>
	</bean>
	
	<!-- 配置hibernate的事務管理器 -->
	<bean id="transactionManager"
		class="org.springframework.orm.jpa.JpaTransactionManager">
		<property name="entityManagerFactory" ref="entityManagerFactory" />
	</bean>

	<!-- 配置開啓註解事務處理 -->
	<tx:annotation-driven transaction-manager="transactionManager"/>

	<!-- 配置springIOC的註解掃描 -->
	<context:component-scan base-package="com.bjsxt"></context:component-scan>
</beans>

二 Hibernate JPA中的CRUD操作

2.1 添加實體類

package com.bjsxt.pojo;

import java.io.Serializable;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

import lombok.Data;

@Entity
@Table(name="ts_users")
@Data
public class Users implements Serializable{
	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	@Id
	@GeneratedValue(strategy=GenerationType.IDENTITY)
	@Column(name="id")
	private Long id;
	
	@Column(name="user_name")
	private String userName;
	
	@Column(name="age")
	private Integer age;
}

2.2 添加UsersDao

package com.bjsxt.dao;

import java.util.List;

import com.bjsxt.pojo.Users;

public interface UsersDao {
	void insertUsers(Users users);
	
	void updateUsers(Users users);
	
	void deleteUsers(Users users);
	
	Users selectUserById(Long id);
}

2.3 添加UsersDaoImpl

package com.bjsxt.dao.impl;

import java.util.List;

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

import org.springframework.stereotype.Repository;

import com.bjsxt.dao.UsersDao;
import com.bjsxt.pojo.Users;

@Repository
public class UsersDaoImpl implements UsersDao {
	
	// 會從entityManagerFactory工廠當中取一個entityManager然後注入給我們的屬性
	@PersistenceContext(name="entityManagerFactory")
	private EntityManager entityManager;

	public void insertUsers(Users users) {
		this.entityManager.persist(users);
	}

	public void updateUsers(Users users) {
		this.entityManager.merge(users);
	}

	public void deleteUsers(Users users) {
		Users users2 = this.selectUserById(users.getId());
		this.entityManager.remove(users2);
	}

	public Users selectUserById(Long id) {
		return this.entityManager.find(Users.class, id);
	}
}

2.4 添加UsersDaoImplTest

package com.bjsxt.dao.impl;

import java.util.List;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.annotation.Rollback;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.transaction.annotation.Transactional;

import com.bjsxt.dao.UsersDao;
import com.bjsxt.pojo.Users;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class UsersDaoImplTest {
	
	@Autowired
	private UsersDao userDao;

	/**
	 * Hibernate: insert into ts_users (age, user_name) values (?, ?)
	 */
	@Test
	@Transactional
	@Rollback(false)
	public void testInsertUsers() {
		Users users = new Users();
		users.setAge(28);
		users.setUserName("索羅");
		this.userDao.insertUsers(users);
	}

	/** 執行結果：
		Hibernate: select users0_.id as id1_0_0_, users0_.age as age2_0_0_, users0_.user_name as user_nam3_0_0_ from ts_users users0_ where users0_.id=?
		Hibernate: update ts_users set age=?, user_name=? where id=?
	 */
	@Test
	@Transactional
	@Rollback(false)
	public void testUpdateUsers() {
		Users users = new Users();
		users.setId(6l);
		users.setAge(28);
		users.setUserName("索羅-二把手");
		this.userDao.updateUsers(users);
	}
	
	/**
	 * 執行結果：
	 	Hibernate: select users0_.id as id1_0_0_, users0_.age as age2_0_0_, users0_.user_name as user_nam3_0_0_ from ts_users users0_ where users0_.id=?
		Hibernate: delete from ts_users where id=?
	 */
	@Test
	@Transactional
	@Rollback(false)
	public void testDeleteUsers() {
		Users users = new Users();
		users.setId(8l);
		this.userDao.deleteUsers(users);
	}

	/**
	 * 執行結果：
		Hibernate: select users0_.id as id1_0_0_, users0_.age as age2_0_0_, users0_.user_name as user_nam3_0_0_ from ts_users users0_ where users0_.id=?
		Users(id=6, userName=索羅-二把手, age=28)
	 */
	@Test
	public void testSelectUserById() {
		Users users = this.userDao.selectUserById(6l);
		System.out.println(users);
	}

}

三 Hibernate JPA中的HQL

3.1 在UsersDao中添加如下代碼

	List<Users> selectUsersByUserName(String userName);

3.2 在UsersDaoImpl添加如下代碼

	public List<Users> selectUsersByUserName(String userName) {
		Query query = this.entityManager.createQuery("from Users where userName=:userName");
		query.setParameter("userName", userName);
		return query.getResultList();
	}

3.3 在測試類中添加如下代碼

	/**
	 * 執行結果：
		Hibernate: select users0_.id as id1_0_, users0_.age as age2_0_, users0_.user_name as user_nam3_0_ from ts_users users0_ where users0_.user_name=?
		[Users(id=6, userName=索羅-二把手, age=28)]
	 */
	@Test
	@Transactional
	public void testSelectUsersByUserName() {
		List<Users> list = this.userDao.selectUsersByUserName("索羅-二把手");
		System.out.println(list);
	}

四 Hibernate JPA中的SQL語句

4.1 在UsersDao中添加如下代碼

	List<Users> selectUsersByUserNameSQL(String userName);

4.2 在UsersDaoImpl中添加如下代碼

	public List<Users> selectUsersByUserNameSQL(String userName) {
		Query query = this.entityManager.createNativeQuery("select * from ts_users where user_name=?", Users.class);
		// 注意，在Hibernate JPA中如果通過?方式來綁定參數，那麼它的參數是從1開始的，而Hibernate中是從0開始的
		query.setParameter(1, userName);
		return query.getResultList();
	}

4.3 在測試類中添加如下代碼

	/**
	 * 執行結果：
		Hibernate: select * from ts_users where user_name=?
		[Users(id=6, userName=索羅-二把手, age=28)]
	 */
	@Test
	@Transactional
	public void testSelectUsersByUserNameSQL() {
		List<Users> list = this.userDao.selectUsersByUserNameSQL("索羅-二把手");
		System.out.println(list);
	}

五 Hibernate JPA中的Criteria操作（QBC查詢）

5.1 在UsersDao中添加如下代碼

	List<Users> selectUsersByUserNameQBC(String userName);

5.2 在UsersDaoImpl中添加如下代碼

	public List<Users> selectUsersByUserNameQBC(String userName) {
		// CriteriaBuilder對象， 創建一個CriteriaQuery,創建查詢對象
		CriteriaBuilder criteriaBuilder = this.entityManager.getCriteriaBuilder();

		// CriteriaQuery對象，執行查詢的Criteria對象
		CriteriaQuery<Users> query = criteriaBuilder.createQuery(Users.class);

		// 獲取要查詢的實體類的對象
		Root<Users> root = query.from(Users.class);
		
		// 封裝查詢條件
		Predicate predicate = criteriaBuilder.equal(root.get("userName"), userName);
		query.where(predicate);
		// 執行查詢
		TypedQuery<Users> typedQuery = this.entityManager.createQuery(query);
		return typedQuery.getResultList();
	}

5.3 在測試類中添加如下代碼

	/**
	 * 執行結果：
		Hibernate: select users0_.id as id1_0_, users0_.age as age2_0_, users0_.user_name as user_nam3_0_ from ts_users users0_ where users0_.user_name=?
		[Users(id=6, userName=索羅-二把手, age=28)]
	 */
	@Test
	@Transactional
	public void testSelectUsersByUserNameQBC() {
		List<Users> list = this.userDao.selectUsersByUserNameQBC("索羅-二把手");
		System.out.println(list);
	}