jpa，试图从实体创建 table，class 未找到 ExpressionVisitor

Question

我在从 Eclipse 中的实体创建表时遇到了一些问题。这个项目最初是在 windows 上的 eclipse 上，我从 mysql 表中创建了实体并将其导入到项目中。一切都很好。昨天我决定从 windows 切换到 ubuntu，因此我只是备份了 eclipse 项目，认为我无论如何都可以从实体创建表。

所以当我右键单击项目 -> JPA 工具 -> 从实体创建表时，

我收到以下错误：

Exception in thread "main" Local Exception Stack: Exception [EclipseLink-30005] (Eclipse Persistence Services - 2.6.0.v20140809-296a69f): org.eclipse.persistence.exceptions.PersistenceUnitLoadingException Exception Description: An exception was thrown while searching for persistence archives with ClassLoader: org.eclipse.persistence.dynamic.DynamicClassLoader@6eceb130 Internal Exception: javax.persistence.PersistenceException: Exception [EclipseLink-28018] (Eclipse Persistence Services - 2.6.0.v20140809-296a69f): org.eclipse.persistence.exceptions.EntityManagerSetupException Exception Description: Predeployment of PersistenceUnit [my-pu] failed. Internal Exception: java.lang.NoClassDefFoundError: org/eclipse/persistence/jpa/jpql/parser/ExpressionVisitor at org.eclipse.persistence.exceptions.PersistenceUnitLoadingException.exceptionSearchingForPersistenceResources(PersistenceUnitLoadingException.java:127) at org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFactoryImpl(PersistenceProvider.java:107) at org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFactory(PersistenceProvider.java:179) at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:55) at org.eclipse.jpt.jpa.eclipselink.core.ddlgen.Main.buildEntityManagerFactory(Main.java:94) at org.eclipse.jpt.jpa.eclipselink.core.ddlgen.Main.execute(Main.java:80) at org.eclipse.jpt.jpa.eclipselink.core.ddlgen.Main.main(Main.java:68) Caused by: javax.persistence.PersistenceException: Exception [EclipseLink-28018] (Eclipse Persistence Services - 2.6.0.v20140809-296a69f): org.eclipse.persistence.exceptions.EntityManagerSetupException Exception Description: Predeployment of PersistenceUnit [my-pu] failed. Internal Exception: java.lang.NoClassDefFoundError: org/eclipse/persistence/jpa/jpql/parser/ExpressionVisitor at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.createPredeployFailedPersistenceException(EntityManagerSetupImpl.java:1973) at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.predeploy(EntityManagerSetupImpl.java:1964) at org.eclipse.persistence.internal.jpa.deployment.JPAInitializer.callPredeploy(JPAInitializer.java:98) at org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFactoryImpl(PersistenceProvider.java:96) ... 5 more Caused by: Exception [EclipseLink-28018] (Eclipse Persistence Services - 2.6.0.v20140809-296a69f): org.eclipse.persistence.exceptions.EntityManagerSetupException Exception Description: Predeployment of PersistenceUnit [my-pu] failed. Internal Exception: java.lang.NoClassDefFoundError: org/eclipse/persistence/jpa/jpql/parser/ExpressionVisitor at org.eclipse.persistence.exceptions.EntityManagerSetupException.predeployFailed(EntityManagerSetupException.java:231) ... 9 more Caused by: java.lang.NoClassDefFoundError: org/eclipse/persistence/jpa/jpql/parser/ExpressionVisitor at org.eclipse.persistence.internal.jpa.metadata.queries.NamedQueryMetadata.addJPAQuery(NamedQueryMetadata.java:105) at org.eclipse.persistence.internal.jpa.metadata.queries.NamedQueryMetadata.process(NamedQueryMetadata.java:192) at org.eclipse.persistence.internal.jpa.metadata.MetadataProject.processQueries(MetadataProject.java:1630) at org.eclipse.persistence.internal.jpa.metadata.MetadataProcessor.addNamedQueries(MetadataProcessor.java:148) at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.predeploy(EntityManagerSetupImpl.java:1915) ... 7 more Caused by: java.lang.ClassNotFoundException: org.eclipse.persistence.jpa.jpql.parser.ExpressionVisitor at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ... 12 more

Wildfly 默认使用 hibernate 作为 JPA 提供程序，我确实将它切换到了 EclipseLink。

Answer 1

您需要将提供程序添加到 persistence.xml 中的持久性单元并确保 eclipse link jar 在 Wildfly classpath

中

<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>

查看更多https://docs.jboss.org/author/display/WFLY8/JPA+Reference+Guide#JPAReferenceGuide-UpdateyourPersistence.xmlforHibernate4.3.0

Answer 2

我在属性-> jpa 中将目标库更改为用户定义的库。

然后我跟着这个啧啧：https://www.youtube.com/watch?v=wjCCQSJVtVQ

基本上：

<persistence-unit name="my-pu" transaction-type="RESOURCE_LOCAL">
    <jta-data-source>java:/forumcsDS</jta-data-source>
    <exclude-unlisted-classes>false</exclude-unlisted-classes>

    <properties>
        <property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
        <property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/forumcs"/>
        <property name="javax.persistence.jdbc.user" value="root"/>
        <property name="javax.persistence.jdbc.password" value="X"/>
        <property name="eclipseLink.ddl-generation" value="drop-and-create-tables"/>
        <property name="eclipseLink.ddl-generation.output-mode" value="database"/>

    </properties>
    </persistence-unit>

然后我切换回旧的 persistence.xml

jpa，试图从实体创建 table，class 未找到 ExpressionVisitor

jpa, trying to create table from entities, class not found ExpressionVisitor

java

jpa

eclipselink

wildfly

wildfly-8