hibernate - javax.persistence.PersistenceException : No Persistence provider for EntityManager named

Question

我正在尝试使用 JPA 为我目前参与的 Java-EE 项目设置持久性，并且我遇到了许多配置问题。目前，我已经在 persistence.xml 中定义了一个 RESOURCE_LOCAL 持久性单元，目的是在解决设置 JTA 持久性单元及其相应的 JTA 数据源的问题之前，在单元测试中使用这个单元并验证所有其他工作。然而，即使是这种“简单”的情况也会导致错误。

详细:

我得到的错误是这样的:

javax.persistence.PersistenceException: No Persistence provider for EntityManager named kronosTestLocal
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:69)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:47)
    at persistence.EntityManagerTest.getStaff(EntityManagerTest.java:56)
    at persistence.EntityManagerTest.setup(EntityManagerTest.java:17)
    ...

抛出错误的代码片段在 JUnit 测试中如下所示:

private final String persistenceUnitName = "kronosTestLocal";
....
final EntityManagerFactory entityManagerFactory =
    Persistence.createEntityManagerFactory(persistenceUnitName);

persistence.xml(在 META-INF 内并在 intellij JPA 方面声明):
(我尝试删除 kronos 持久性单元，以防它以某种方式干扰，但这没有帮助)

<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="2.0">
    <persistence-unit name="kronos" transaction-type="JTA">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <jta-data-source>jdbc/kronos-database</jta-data-source>

        <class>persistence.entities.DaySlotsEntity</class>
        <class>persistence.entities.DaysEntity</class>
        <class>persistence.entities.EmailNotificationsEntity</class>
        <class>persistence.entities.EmailSendingTimestampsEntity</class>
        <class>persistence.entities.GroupSlotsEntity</class>
        <class>persistence.entities.GroupsEntity</class>
        <class>persistence.entities.InterviewerEntity</class>
        <class>persistence.entities.InterviewerPreferencesEntity</class>
        <class>persistence.entities.InterviewerUnavailableDaysEntity</class>
        <class>persistence.entities.InterviewerWorkloadEntity</class>
        <class>persistence.entities.InterviewsEntity</class>
        <class>persistence.entities.PreferenceTypesEntity</class>
        <class>persistence.entities.PreferencesEntity</class>
        <class>persistence.entities.StaffEntity</class>
        <class>persistence.entities.StudentsEntity</class>
        <class>persistence.entities.SwapsEntity</class>
    </persistence-unit>

    <persistence-unit name="kronosTestLocal" transaction-type="RESOURCE_LOCAL">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>

        <class>persistence.entities.DaySlotsEntity</class>
        <class>persistence.entities.DaysEntity</class>
        <class>persistence.entities.EmailNotificationsEntity</class>
        <class>persistence.entities.EmailSendingTimestampsEntity</class>
        <class>persistence.entities.GroupSlotsEntity</class>
        <class>persistence.entities.GroupsEntity</class>
        <class>persistence.entities.InterviewerEntity</class>
        <class>persistence.entities.InterviewerPreferencesEntity</class>
        <class>persistence.entities.InterviewerUnavailableDaysEntity</class>
        <class>persistence.entities.InterviewerWorkloadEntity</class>
        <class>persistence.entities.InterviewsEntity</class>
        <class>persistence.entities.PreferenceTypesEntity</class>
        <class>persistence.entities.PreferencesEntity</class>
        <class>persistence.entities.StaffEntity</class>
        <class>persistence.entities.StudentsEntity</class>
        <class>persistence.entities.SwapsEntity</class>

        <properties>
            <property name="hibernate.connection.url" value="jdbc:postgresql://localhost:5432/kronos"/>
            <property name="hibernate.connection.driver_class" value="org.postgresql.Driver"/>
            <property name="hibernate.connection.username" value="postgres"/>
            <property name="hibernate.connection.password" value="****"/>
            <property name="show_sql" value="true"/>
            <property name="hibernate.dialect"  value="org.hibernate.dialect.PostgreSQLDialect"/>
        </properties>
    </persistence-unit>
</persistence>

Maven pom.xml:

<?xml version="1.0" encoding="UTF-8"?>
<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">
    <parent>
        <artifactId>kronos</artifactId>
        <groupId>kronos</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>ejb</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>3.6.7.Final</version>
        </dependency>

        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <version>9.2-1003-jdbc4</version>
        </dependency>

        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.6</version>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
        </dependency>

        <dependency>
            <groupId>org.mockito</groupId>
            <artifactId>mockito-all</artifactId>
            <version>1.9.5</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-ejb-plugin</artifactId>
                <version>2.3</version>
                <configuration>
                    <ejbVersion>3.2</ejbVersion>
                    <archive>
                        <manifest>
                            <addClasspath>true</addClasspath>
                        </manifest>
                    </archive>
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.7</source>
                    <target>1.7</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

从我的研究中，我看到很多人遇到了类似的问题，但据我所知，我没有犯任何常见的错误。我们中的一些人已经尝试解决这个问题一段时间了，所以欢迎任何帮助。

Answer 1

如果您是从 JUnit 测试中执行此操作并使用 maven，则 persistence.xml应位于 src/test/resources/META-INF/persistence.xml它将在测试执行时放入正确的位置。 src/main/resources/META-INF/ 中的文件未使用，因为它不在 test-jar 中的路径。