创建数据库表
CREATE TABLE cst_customer (
cust_id BIGINT(32) NOT NULL AUTO_INCREMENT COMMENT '客户编号(主键)',
cust_name VARCHAR(32) NOT NULL COMMENT '客户名称(公司名称)',
cust_source VARCHAR(32) DEFAULT NULL COMMENT '客户信息来源',
cust_industry VARCHAR(32) DEFAULT NULL COMMENT '客户所属行业',
cust_level VARCHAR (32) DEFAULT NULL COMMENT '客户级别',
cust_address VARCHAR (128) DEFAULT NULL COMMENT '客户联系地址',
cust_phone VARCHAR(64) DEFAULT NULL COMMENT '客户联系电话',
PRIMARY KEY (`cust_id`)
) ENGINE=INNODB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
创建一个空的maven工程,导入maven依赖坐标
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.hibernate.version>5.0.7.Final</project.hibernate.version>
</properties>
<dependencies>
<!-- junit -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<!-- hibernate对jpa的支持包 -->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>${project.hibernate.version}</version>
</dependency>
<!-- c3p0 -->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-c3p0</artifactId>
<version>${project.hibernate.version}</version>
</dependency>
<!-- log日志 -->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<!-- Mysql and MariaDB -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.6</version>
</dependency>
</dependencies>
在resources中创建META-INF文件夹,里面创建persistence.xml配置文件
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="2.0">
<!--name:持久化单元名称
transaction-type:事务管理的方式
JTA:分布式事务管理
RESOURCE_LOCAL:本地事务管理方式
-->
<persistence-unit name="myJpa" transaction-type="RESOURCE_LOCAL">
<!--jpa的实现方式-->
<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
<!--可选配置:配置jpa实现方的配置信息-->
<properties>
<!--数据库信息:用户名,密码,驱动,数据库地址-->
<property name="javax.persistence.jdbc.user" value="root"/>
<property name="javax.persistence.jdbc.password" value="123456"/>
<property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
<property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/jpa?useSSL=false&useUnicode=true&characterEncoding=utf8"/>
<!--配置jpa实现方(hibernate)的配置信息
显示sql:false|true
自动创建数据库表: hibernate.hbm2ddl.auto
create: 程序运行时创建数据库表(如果有表,先删除在创建)
update: 程序运行时创建表(如果有表,不会创建表)
none: 不会创建表
-->
<property name="hibernate.show_sql" value="true"/>
<property name="hibernate.hbm2ddl.auto" value="update"/>
</properties>
</persistence-unit>
</persistence>
编写实体类
package com.feng.pojo;
import org.hibernate.annotations.GeneratorType;
import javax.persistence.*;
@Entity
@Table(name = "cst_customer")
public class Customer {
@Id
@GeneratedValue(strategy = GenerationType.TABLE)
@Column(name = "cust_id")
private Long custId;
@Column(name = "cust_name")
private String custName;
@Column(name = "cust_source")
private String custSource;
@Column(name = "cust_level")
private String custLevel;
@Column(name = "cust_Industry")
private String custIndustry;
@Column(name = "cust_phone")
private String custPhone;
@Column(name = "cust_address")
private String custAddress;
public Long getCustId() {
return custId;
}
public void setCustId(Long custId) {
this.custId = custId;
}
public String getCustName() {
return custName;
}
public void setCustName(String custName) {
this.custName = custName;
}
public String getCustSource() {
return custSource;
}
public void setCustSource(String custSource) {
this.custSource = custSource;
}
public String getCustLevel() {
return custLevel;
}
public void setCustLevel(String custLevel) {
this.custLevel = custLevel;
}
public String getCustIndustry() {
return custIndustry;
}
public void setCustIndustry(String custIndustry) {
this.custIndustry = custIndustry;
}
public String getCustPhone() {
return custPhone;
}
public void setCustPhone(String custPhone) {
this.custPhone = custPhone;
}
public String getCustAddress() {
return custAddress;
}
public void setCustAddress(String custAddress) {
this.custAddress = custAddress;
}
@Override
public String toString() {
return "Customer{" +
"custId=" + custId +
", custName='" + custName + '\'' +
", custSource='" + custSource + '\'' +
", custLevel='" + custLevel + '\'' +
", custIndustry='" + custIndustry + '\'' +
", custPhone='" + custPhone + '\'' +
", custAddress='" + custAddress + '\'' +
'}';
}
}
编写测试类
package com.feng.test;
import com.feng.pojo.Customer;
import org.junit.Test;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;
public class JpaTest {
@Test
public void testSave(){
EntityManagerFactory factory = Persistence.createEntityManagerFactory("myJpa");
EntityManager em = factory.createEntityManager();
EntityTransaction tx = em.getTransaction();
tx.begin();
Customer customer = new Customer();
customer.setCustName("传智播客");
customer.setCustIndustry("教育");
em.persist(customer);
tx.commit();
em.close();
factory.close();
}
}
可以提取一个公共的工具类
package com.feng.untils;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
public class JpaUtils {
private static EntityManagerFactory factory;
static {
factory = Persistence.createEntityManagerFactory("myJpa");
}
public static EntityManager getEntityManager() {
return factory.createEntityManager();
}
}
用工具类编写我们的测试类
package com.feng.test;
import com.feng.pojo.Customer;
import com.feng.untils.JpaUtils;
import org.junit.Test;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;
public class JpaTest {
@Test
public void testSave(){
EntityManager em = JpaUtils.getEntityManager();
EntityTransaction tx = em.getTransaction();
tx.begin();
Customer customer = new Customer();
customer.setCustName("传智播客");
customer.setCustIndustry("教育");
em.persist(customer);
tx.commit();
em.close();
}
@Test
public void testFind(){
EntityManager em = JpaUtils.getEntityManager();
EntityTransaction tx = em.getTransaction();
tx.begin();
Customer customer = em.find(Customer.class,1L);
System.out.println(customer);
tx.commit();
em.close();
}
@Test
public void testReference() {
EntityManager entityManager = JpaUtils.getEntityManager();
EntityTransaction tx = entityManager.getTransaction();
tx.begin();
Customer customer = entityManager.getReference(Customer.class, 1l);
System.out.print(customer);
tx.commit();
entityManager.close();
}
@Test
public void testRemove(){
EntityManager em = JpaUtils.getEntityManager();
EntityTransaction tx = em.getTransaction();
tx.begin();
Customer customer = em.find(Customer.class,1L);
em.remove(customer);
System.out.println(customer);
tx.commit();
em.close();
}
@Test
public void testUpdate(){
EntityManager em = JpaUtils.getEntityManager();
EntityTransaction tx = em.getTransaction();
tx.begin();
Customer customer = em.find(Customer.class,1L);
customer.setCustIndustry("it尚硅谷");
Customer customer1 = em.merge(customer);
System.out.println(customer1);
tx.commit();
em.close();
}
}
查询全部数据,新建一个测试类
package com.feng.test;
import com.feng.untils.JpaUtils;
import org.junit.Test;
import javax.persistence.EntityManager;
import javax.persistence.EntityTransaction;
import javax.persistence.Query;
import java.util.List;
public class JpaSqlTest {
@Test
public void testQueryAll(){
EntityManager manager = JpaUtils.getEntityManager();
EntityTransaction tx = manager.getTransaction();
tx.begin();
String jqpl="from Customer";
Query query = manager.createQuery(jqpl);
List resultList = query.getResultList();
for (Object o : resultList) {
System.out.println(o);
}
tx.commit();
manager.close();
}
@Test
public void testQueryOrders(){
EntityManager manager = JpaUtils.getEntityManager();
EntityTransaction tx = manager.getTransaction();
tx.begin();
String jqpl="from Customer order by custId desc";
Query query = manager.createQuery(jqpl);
List resultList = query.getResultList();
for (Object o : resultList) {
System.out.println(o);
}
tx.commit();
manager.close();
}
@Test
public void testCount(){
EntityManager manager = JpaUtils.getEntityManager();
EntityTransaction tx = manager.getTransaction();
tx.begin();
String jqpl="select count(custId) from Customer ";
Query query = manager.createQuery(jqpl);
Object singleResult = query.getSingleResult();
System.out.println(singleResult);
tx.commit();
manager.close();
}
@Test
public void testPaged(){
EntityManager manager = JpaUtils.getEntityManager();
EntityTransaction tx = manager.getTransaction();
tx.begin();
String jqpl="from Customer ";
Query query = manager.createQuery(jqpl);
query.setFirstResult(0);
query.setMaxResults(2);
List resultList = query.getResultList();
for (Object o : resultList) {
System.out.println(o);
}
tx.commit();
manager.close();
}
@Test
public void testCondition() {
EntityManager em = JpaUtils.getEntityManager();
EntityTransaction tx = em.getTransaction();
tx.begin();
String jpql = "from Customer where custName like ? ";
Query query = em.createQuery(jpql);
query.setParameter(1,"传智播客%");
List list = query.getResultList();
for(Object obj : list) {
System.out.println(obj);
}
tx.commit();
em.close();
}
}