Question

我正在尝试配置一个简单的JPA项目而且我很困难。

我有一个工作的数据源（MySQL）＆amp; GlassFish有多个表格。

我做了以下步骤（Intellij生成的所有文件）：

使用Java EE Persistance和Hibernate Provider创建新项目。
导入具有Student表的数据库。
使用Intellij IDE生成实体类。
从Maven导入Hibernate-entitymanager库。
导入MySQL连接器。
尝试运行一个简单的JPA程序来创建新行，但我得到一个例外：

没有EntityManager的持久性提供程序名为persistenceUnit

可能是什么问题？我几乎尝试了每个教程和每个问题，但没有成功！

请帮助我！

（有时持久性提供程序中的Hibernate为红色）

持久性：

    <?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="2.0">

    <persistence-unit name="NewPersistenceUnit">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <class>modules.CourseEntity</class>
        <class>modules.StuCouEntity</class>
        <class>modules.StudentsEntity</class>
        <class>modules.TeacherEntity</class>
        <properties>
            <property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306"/>
            <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>
            <property name="hibernate.connection.username" value="root"/>
            <property name="hibernate.connection.password" value="123456"/>
            <property name="hibernate.archive.autodetection" value="class"/>
            <property name="hibernate.show_sql" value="true"/>
            <property name="hibernate.format_sql" value="true"/>
            <property name="hbm2ddl.auto" value="update"/>
        </properties>
    </persistence-unit>
</persistence>

Main.java：

import modules.StudentsEntity;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
public class MainClass
{
    public static void main(String[] args)
    {
        StudentsEntity stu = new StudentsEntity();
        stu.setName("David");

        EntityManagerFactory emf = Persistence.createEntityManagerFactory("persistenceUnit");
        EntityManager em = emf.createEntityManager();

        em.getTransaction().begin();
        try
        {
            em.persist(stu);
            em.getTransaction().commit();
        }
        catch (Exception ex)
        {
            System.out.println(ex.getMessage());
            ex.printStackTrace();
            em.getTransaction().rollback();
        }
        finally
        {
            em.close();
        }



    }
}

错误：

June 16, 2017 5:47:07 PM org.hibernate.annotations.common.Version <clinit>
INFO: HCANN000001: Hibernate Commons Annotations {4.0.1.Final}
June 16, 2017 5:47:07 PM org.hibernate.Version logVersion
INFO: HHH000412: Hibernate Core {4.1.5.Final}
June 16, 2017 5:47:07 PM org.hibernate.cfg.Environment <clinit>
INFO: HHH000206: hibernate.properties not found
June 16, 2017 5:47:07 PM org.hibernate.cfg.Environment buildBytecodeProvider
INFO: HHH000021: Bytecode provider name : javassist
Exception in thread "main" javax.persistence.PersistenceException: No Persistence provider for EntityManager named persistenceUnit
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:84)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:54)
    at MainClass.main(MainClass.java:17)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)

Answer 1

您已定义

<persistence-unit name="NewPersistenceUnit">

尝试拨打Persistence.createEntityManagerFactory("persistenceUnit");

时

将NewPersistenceUnit更改为persistenceUnit

无法使用Intellij配置JPA

1 个答案: