使用Hibernate 5和JPA连接到MySQL Server时出错

Question

我正在升级到Hibernate 5和JPA，并且无法连接到MySQL Server 5.7.18（Java 8，ojdbc8）。 从命令行使用mysql可以很好地连接和访问数据库，因此我知道服务器已启动，并且用户名/密码正确。 PeopleEntity.class使用注释而不是映射文件。

例外是“无法创建请求的服务[org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]”。 我已经尝试了“ jdbc：oracle：thin：@localhost：3306：TestHibernate”和“ jdbc：mysql：// localhost：3306 / TestHibernate”

任何有关如何纠正问题的建议将不胜感激。

final Map<String, String> properties = new HashMap<String, String>();
properties.put("javax.persistence.jdbc.user", LoginInfo.getLoginInfo().getUsername());
properties.put("javax.persistence.jdbc.password", LoginInfo.getLoginInfo().getPassword());
properties.put("javax.persistence.jdbc.url", "jdbc:oracle:thin:@localhost:3306:TestHibernate");
// or
properties.put("javax.persistence.jdbc.url", "jdbc:mysql://localhost:3306/TestHibernate");
try {
    Persistence.createEntityManagerFactory("PeopleEntity", properties);
} catch (final PersistenceException error) {
    Logger.error(getClass(), error.getMessage());
}

来自persistence.xml

<persistence
    xmlns="http://xmlns.jcp.org/xml/ns/persistence"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence
http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd"
    version="2.1">

    <persistence-unit
        name="PeopleEntity"
        transaction-type="RESOURCE_LOCAL">
        <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
        <class>com.billsdesk.util.hibernate.tests.PeopleEntity</class>
        <properties>
            <property
                name="hibernate.connection.driver_class"
                value="com.mysql.jdbc.Driver"></property>
            <property
                name="javax.persistence.jdbc.driver"
                value="oracle.jdbc.OracleDriver"></property>
            <property
                name="hibernate.dialect"
                value="org.hibernate.dialect.MySQL5Dialect" />

            <!-- URL, user, and password are passed as properties -->

        </properties>
    </persistence-unit>
</persistence>

从pom.xml

<dependencies>

    <!-- Hibernate -->

    <dependency>
        <groupId>com.oracle.jdbc</groupId>
        <artifactId>ojdbc8</artifactId>
        <version>12.2.0.1</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>6.0.6</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-core -->
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>5.2.10.Final</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-entitymanager -->
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>5.2.10.Final</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/javax.persistence/persistence-api -->
    <dependency>
        <groupId>javax.persistence</groupId>
        <artifactId>persistence-api</artifactId>
        <version>1.0.2</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.apache.logging.log4j/log4j-core -->
    <dependency>
        <groupId>org.apache.logging.log4j</groupId>
        <artifactId>log4j-core</artifactId>
        <version>2.8.2</version>
    </dependency>
</dependencies>

休眠痕迹

14:00:45.861 [main] INFO  org.hibernate.Version - HHH000412: Hibernate Core {5.2.10.Final}
14:00:45.862 [main] INFO  org.hibernate.cfg.Environment - HHH000206: hibernate.properties not found
14:00:45.910 [main] INFO  org.hibernate.annotations.common.Version - HCANN000001: Hibernate Commons Annotations {5.0.1.Final}
14:00:46.088 [main] WARN  org.hibernate.orm.connections.pooling - HHH10001002: Using Hibernate built-in connection pool (not for production use!)
14:00:46.127 [main] INFO  org.hibernate.orm.connections.pooling - HHH10001005: using driver [oracle.jdbc.OracleDriver] at URL [jdbc:oracle:thin:@localhost:3306:TestHibernate]
14:00:46.127 [main] INFO  org.hibernate.orm.connections.pooling - HHH10001001: Connection properties: {user=sa, password=****}
14:00:46.128 [main] INFO  org.hibernate.orm.connections.pooling - HHH10001003: Autocommit mode: false
14:00:46.130 [main] INFO  org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl - HHH000115: Hibernate connection pool size: 20 (min=1)
2017-07-06 14:00:46 SEVERE Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]

Answer 1

尽管MySQL是Oracle Corporation的产品，“ Oracle”数据库产品和“ MySQL”数据库产品却是两个截然不同的生物。 使用“ Oracle” JDBC驱动程序永远无法与MySQL数据库服务器一起使用。

作为最低限度的实现，我得到了以下内容仅可处理四（4）个文件。 这可能不是“最佳”或“最现代”的方式，但是它确实对我有用。

pom.xml

<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.example.demo</groupId>
  <artifactId>so44959525</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <dependencies>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>5.2.10.Final</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>6.0.6</version>
    </dependency>
  </dependencies>
</project>

src / main / resources / hibernate.cfg.xml

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

    <session-factory>

        <!-- Database connection properties -->
        <property name="connection.url">jdbc:mysql://localhost:3307/mydb</property>
        <property name="connection.username">root</property>
        <property name="connection.password">whatever</property>
        <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>

        <!--
        Automatic schema generation. Possible values:

        none (default value), create-only, drop, create, create-drop, validate, and update

        https://docs.jboss.org/hibernate/orm/5.2/userguide/html_single/Hibernate_User_Guide.html#configurations-hbmddl
        -->
        <property name="hbm2ddl.auto">create</property>

        <!-- JDBC connection pool (use the built-in) -->
        <property name="connection.pool_size">1</property>

        <!-- Disable the second-level cache  -->
        <property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>

        <!-- Echo all executed SQL to stdout -->
        <property name="show_sql">true</property>
        <property name="format_sql">false</property>

        <mapping class="com.example.demo.Person"/>

    </session-factory>

</hibernate-configuration>

src / main / java / com / example / demo / Person.java

package com.example.demo;

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

@Entity
public class Person {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;
    public int getId() { return id; }

    private String name;
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }

    public Person() {
        // no-argument constructor required by Hibernate
    }

    public Person (String name) {
        this.name = name;
    }
}

src / main / java / com / example / demo / DemoMain.java

package com.example.demo;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;

public class DemoMain {

    public static void main(String[] args) {
        final StandardServiceRegistry registry = new StandardServiceRegistryBuilder()
                .configure() // configures settings from hibernate.cfg.xml
                .build();
        try (SessionFactory sessionFactory = new MetadataSources(registry).buildMetadata().buildSessionFactory()) {
            Session session = sessionFactory.openSession();
            session.beginTransaction();
            for (String newGuy : new String[] { "Rodd", "Todd" }) {
                int newId = (int) session.save(new Person(newGuy));
                System.out.printf("\"%s\" inserted as id %d%n", newGuy, newId);
            }
            session.getTransaction().commit();
            session.close();
        } catch (Exception e) {
            e.printStackTrace(System.err);
        } finally {
            StandardServiceRegistryBuilder.destroy(registry);
        }
    }

}