如何配置persistence.xml提供程序標記

Question

嘿，我正在學習這個東西，我不完全理解它，我有一個問題，我不知道在persistence.xml中提供者標記中寫什麼

這裏是我的persistence.xml和pom.xml的文件：

的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"> 
<modelVersion>4.0.0</modelVersion> 

<groupId>com.test.jpa</groupId> 
<artifactId>JPAProject</artifactId> 
<version>1.0-SNAPSHOT</version> 
<packaging>war</packaging> 

<dependencies> 
    <dependency> 
     <groupId>javax</groupId> 
     <artifactId>javaee-api</artifactId> 
     <version>7.0</version> 
    </dependency> 

    <dependency> 
     <groupId>mysql</groupId> 
     <artifactId>mysql-connector-java</artifactId> 
     <version>5.1.36</version> 
    </dependency> 
</dependencies> 

<build> 
    <finalName>JPAProject</finalName> 
    <plugins> 
     <plugin> 
      <groupId>org.apache.maven.plugins</groupId> 
      <artifactId>maven-war-plugin</artifactId> 
      <version>2.4</version> 
     </plugin> 
    </plugins> 
</build> 

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="Database" transaction-type="RESOURCE_LOCAL"> 
    <class>models.Employee</class> 
    <provider>WHAT TO WRITE HERE ?</provider> 
    <properties> 
     <property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost/jpa"/> 
     <property name="javax.persistence.jdbc.user" value="root"/> 
     <property name="javax.persistence.jdbc.password" value="root"/> 
     <property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/> 
    </properties> 
</persistence-unit> 

Answer 1

在provider標籤你需要包括供應商特定PersistenceProvider實現。

請參考this discussion;你可能會對此有所瞭解。

回答你的問題： -

如果你想使用的EclipseLink實現JPA的請使用provider標籤像below--

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

OR

<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider> 

爲Hibernet實施JPA。