Question

我在eclipse中从实体创建表时遇到了一些麻烦。这个项目最初是在windows上的eclipse上，我从mysql表创建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，以为我可以从实体创建表格。

所以当我右键点击项目时 - ＆gt; JPA工具 - ＆gt;从实体创建表，

我收到以下错误：

线程中的异常＆＃34; main＆＃34;本地异常堆栈：异常[EclipseLink-30005]（Eclipse Persistence Services - 2.6.0.v20140809-296a69f）：org.eclipse.persistence.exceptions.PersistenceUnitLoadingException 异常描述：使用ClassLoader搜索持久性归档时抛出异常：org.eclipse.persistence.dynamic.DynamicClassLoader@6eceb130 内部异常：javax.persistence.PersistenceException：异常[EclipseLink-28018]（Eclipse Persistence Services - 2.6.0.v20140809-296a69f）：org.eclipse.persistence.exceptions.EntityManagerSetupException 异常说明：PersistenceUnit [my-pu]的预部署失败。内部异常：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）在org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFactory（PersistenceProvider.java:179）在javax.persistence.Persistence.createEntityManagerFactory（Persistence.java:55）在org.eclipse.jpt.jpa.eclipselink.core.ddlgen.Main.buildEntityManagerFactory（Main.java:94）在org.eclipse.jpt.jpa.eclipselink.core.ddlgen.Main.execute（Main.java:80）在org.eclipse.jpt.jpa.eclipselink.core.ddlgen.Main.main（Main.java:68）引发者：javax.persistence.PersistenceException：异常[EclipseLink-28018]（Eclipse Persistence Services - 2.6.0.v20140809-296a69f）：org.eclipse.persistence.exceptions.EntityManagerSetupException 异常说明：PersistenceUnit [my-pu]的预部署失败。内部异常：java.lang.NoClassDefFoundError：org / eclipse / persistence / jpa / jpql / parser / ExpressionVisitor at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.createPredeployFailedPersistenceException（EntityManagerSetupImpl.java:1973）在org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.predeploy（EntityManagerSetupImpl.java:1964）在org.eclipse.persistence.internal.jpa.deployment.JPAInitializer.callPredeploy（JPAInitializer.java:98）在org.eclipse.persistence.jpa.PersistenceProvider.createEntityManagerFactoryImpl（PersistenceProvider.java:96） ......还有5个引起：异常[EclipseLink-28018]（Eclipse Persistence Services - 2.6.0.v20140809-296a69f）：org.eclipse.persistence.exceptions.EntityManagerSetupException 异常说明：PersistenceUnit [my-pu]的预部署失败。内部异常：java.lang.NoClassDefFoundError：org / eclipse / persistence / jpa / jpql / parser / ExpressionVisitor at org.eclipse.persistence.exceptions.EntityManagerSetupException.predeployFailed（EntityManagerSetupException.java:231） ......还有9个引起：java.lang.NoClassDefFoundError：org / eclipse / persistence / jpa / jpql / parser / ExpressionVisitor at org.eclipse.persistence.internal.jpa.metadata.queries.NamedQueryMetadata.addJPAQuery（NamedQueryMetadata.java:105）在org.eclipse.persistence.internal.jpa.metadata.queries.NamedQueryMetadata.process（NamedQueryMetadata.java:192）在org.eclipse.persistence.internal.jpa.metadata.MetadataProject.processQueries（MetadataProject.java:1630）在org.eclipse.persistence.internal.jpa.metadata.MetadataProcessor.addNamedQueries（MetadataProcessor.java:148） at org.eclipse.persistence.internal.jpa.EntityManagerSetupImpl.predeploy（EntityManagerSetupImpl.java:1915） ......还有7个引起：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） ......还有12个

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

Answer 1

我将目标库更改为properties-＆gt;中的用户定义库。 JPA。

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

Answer 2

您需要在persistence.xml中将提供程序添加到持久性单元并确保eclipse链接jar在Wildfly类路径中

<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

jpa，尝试从实体创建表，未找到类ExpressionVisitor

2 个答案: