Question

我正在尝试使用EclipseLink学习JPA。我正在使用Mysql作为数据库。我已经添加了所有必需的依赖项，下面是我的pom.xml

    <dependency>
        <groupId>org.eclipse.persistence</groupId>
        <artifactId>eclipselink</artifactId>
        <version>2.7.0</version>
        <exclusions>
            <exclusion>
                <groupId>org.eclipse.persistence</groupId>
                <artifactId>javax.persistence</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>org.eclipse.persistence</groupId>
        <artifactId>javax.persistence</artifactId>
        <version>2.1.1</version>
    </dependency>

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.11</version>
        <scope>runtime</scope>
    </dependency>

</dependencies>

问题是，即使maven已下载了mysql jdbc连接器的所有必需jar，我仍收到异常描述：配置错误。找不到类[com.mysql.cj.jdbc.Driver]。以下是我使用的版本： 1. Mysql JDBC连接器：8.0.11 2. Eclipselink：2.7.1 3. JPA：2.2.0

随附的是我的Maven依赖项jar的屏幕截图。

我在stackoverflow上尝试了其他线程的所有建议，但无法解决问题。

感谢您的帮助，并预先感谢！

下面是我的persistence.xml

<?xml version="1.0" encoding="UTF-8"?>

<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
   xsi:schemaLocation="http://java.sun.com/xml/ns/persistence 
   http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">

   <persistence-unit name="Eclipselink_JPA" transaction-type="RESOURCE_LOCAL">

      <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
      <exclude-unlisted-classes>false</exclude-unlisted-classes>

      <properties>
         <property name="javax.persistence.jdbc.driver" value="com.mysql.cj.jdbc.Driver"/>
         <property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/jpadb"/>
         <property name="javax.persistence.jdbc.user" value="root"/>
         <property name="javax.persistence.jdbc.password" value="root"/>
         <property name="eclipselink.logging.level" value="FINE"/>
         <property name="eclipselink.ddl-generation" value="create-tables"/>
      </properties>

   </persistence-unit>
</persistence>

此外，添加错误堆栈跟踪：

[EL Fine]：服务器：2018-06-24 17：33：10.619--Thread（Thread [main，5，main]）-配置的服务器平台：org.eclipse.persistence.platform.server.NoServerPlatform [EL信息]：2018-06-24 17：33：11.065--ServerSession（1101598632）-Thread（Thread [main，5，main]）-EclipseLink，版本：Eclipse Persistence Services-2.6.5.v20170607- b3d05bd [EL Severe]：ejb：2018-06-24 17：33：11.068--ServerSession（1101598632）-Thread（Thread [main，5，main]）-异常[EclipseLink-4003]（Eclipse Persistence Services-2.6 .5.v20170607-b3d05bd）：org.eclipse.persistence.exceptions.DatabaseException 异常描述：配置错误。找不到类[com.mysql.cj.jdbc.Driver]。线程“主”中的异常javax.persistence.PersistenceException：异常[EclipseLink-4003]（Eclipse Persistence Services-2.6.5.v20170607-b3d05bd）：org.eclipse.persistence.exceptions.DatabaseException 异常描述：配置错误。找不到类[com.mysql.cj.jdbc.Driver]。在org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy（EntityManagerSetupImpl.java:818）在org.eclipse.persistence.internal.jpa.EntityManagerFactoryDelegate.getAbstractSession（EntityManagerFactoryDelegate.java:207）在org.eclipse.persistence.internal.jpa.EntityManagerFactoryDelegate.createEntityManagerImpl（EntityManagerFactoryDelegate.java:307）在org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.createEntityManagerImpl（EntityManagerFactoryImpl.java:337）在org.eclipse.persistence.internal.jpa.EntityManagerFactoryImpl.createEntityManager（EntityManagerFactoryImpl.java:303）在实践中.JPA.persistence.App.main（App.java:17）由以下原因引起：异常[EclipseLink-4003]（Eclipse Persistence Services-2.6.5.v20170607-b3d05bd）：org.eclipse.persistence.exceptions.DatabaseException 异常描述：配置错误。找不到类[com.mysql.cj.jdbc.Driver]。在org.eclipse.persistence.exceptions.DatabaseException.configurationErrorClassNotFound（DatabaseException.java:89）在org.eclipse.persistence.sessions.DefaultConnector.loadDriverClass（DefaultConnector.java:267）在org.eclipse.persistence.sessions.DefaultConnector.connect（DefaultConnector.java:85）在org.eclipse.persistence.sessions.DatasourceLogin.connectToDatasource（DatasourceLogin.java:162）在org.eclipse.persistence.internal.sessions.DatabaseSessionImpl.setOrDetectDatasource（DatabaseSessionImpl.java:214）在org.eclipse.persistence.internal.sessions.DatabaseSessionImpl.loginAndDetectDatasource（DatabaseSessionImpl.java:776）在org.eclipse.persistence.internal.jpa.EntityManagerFactoryProvider.login（EntityManagerFactoryProvider.java:265）在org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.deploy（EntityManagerSetupImpl.java:734） ...还有5个

Answer 1

我的项目使用MySQL和JPA的EclipseLink实现，并且运行良好。我的pom文件：

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.19</version>
</dependency>
<dependency>
    <groupId>org.eclipse.persistence</groupId>
    <artifactId>org.eclipse.persistence.jpa</artifactId>
    <version>2.7.6</version>
</dependency>

配置错误。找不到类[com.mysql.cj.jdbc.Driver]。 EclipseLink，MySQL驱动程序

1 个答案: