环境:Windows 7、NetBean 6.9(包括GlassFish v3、Java EE 6)、MySQL server
我已经在 MySQL 数据库中创建了表,并通过右键单击项目并选择“ create entity from database
”来使用 NetBean 的功能(对不起,如果措辞错误,因为我的 NetBean 是日文的)
这将创建实体。
现在我去测试我是否可以通过实体管理器访问数据库。
tmp.java
package local.test.tmp;
import Resources.Users;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.EntityManager;
import javax.persistence.Query;
import java.util.List;
/**
*
* @author m-t
*/
public class Tmp {
private static EntityManagerFactory factory;
private static final String WEB_PU = "WebApplication1PU";
public static void main(String args[]) {
factory = Persistence.createEntityManagerFactory(WEB_PU);
EntityManager em = factory.createEntityManager();
//read existing entries and write to concole
Query q = em.createQuery("select * from users");
List<Users> userList = q.getResultList();
for(Users u : userList) {
System.out.println(u);
}
}
}
持久性.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">
<!-- orignal
<persistence-unit name="WebApplication1PU" transaction-type="JTA">
<jta-data-source>masatoJNDI</jta-data-source>
<properties/>
</persistence-unit>
-->
<persistence-unit name="WebApplication1PU" transaction-type="JTA">
<jta-data-source>masatoJNDI</jta-data-source>
<properties>
<property name="toplink.jdbc.user" value="masato" />
<property name="toplink.jdbc.password" value="foobar" />
</properties>
</persistence-unit>
</persistence>
当我运行 Tmp.java 时,我可以看到它在以下位置失败:
factory = Persistence.createEntityManagerFactory(WEB_PU);
错误信息:
Exception in thread "main" javax.persistence.PersistenceException: No Persistence
provider for EntityManager named WebApplication1PU
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:84)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:54)
at local.test.tmp.Tmp.main(Tmp.java:24)
我检查了测试代码中持久性单元“WebApplication1PU”的拼写与persistence.xml匹配,它是正确的。
persistence.xml 位于...它是日文的,我不知道英文怎么写 :(
让我试试..
project
|-------web page
|-------test package
|-------lib
|-------enterprise bean
|-------*** file //blah file, I can't translate..
|-----MNIFEST.MF
|-----faces-cofig.xml
|-----persistence.xml //HERE!!
由于失败是在工厂尝试在 persistence.xml 中定位持久性单元的开始,我完全糊涂了。有什么我应该验证的吗?
如果您需要更多说明,请告诉我。
更新
我尝试了建议的可能解决方案,但没有运气。返回相同的错误消息。是的,netbean 6.9 默认提供程序是 toplink。
我做了什么:
将提供程序添加到 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="NoJSFPU" transaction-type="JTA">
<provider>oracle.toplink.essentials.PersistenceProvider</provider>
<jta-data-source>masatoJNDI</jta-data-source>
<properties>
<property name="toplink.jdbc.url" value="jdbc:mysql://localhost:3306/mytest"/>
<property name="toplink.jdbc.driver" value="com.mysql.jdbc.Driver"/>
<property name="toplink.jdbc.user" value="masato" />
<property name="toplink.jdbc.password" value="mocha123" />
</properties>
</persistence-unit>
</persistence>
似乎大多数人在我的情况下都取得了成功。我现在开始认为我如何运行测试文件或文件所在的位置可能存在问题?
我从 netbean 执行的 Tmp.java 位于:
project
|------web page
|------source package
| |-----------local.test.session
|-----------local.test.tmp
|------------------Tmp.java //HERE
我不确定这是否重要。
更新 2
我已将包含 toplink-essential.jar 和 toplink-essential-agent.jar 的 toplink lib 添加到我的项目的 lib 目录中,现在我在原始错误之上遇到了新错误,但我相信我越来越近了。
看起来persistence.xml中的版本属性有问题......???
Exception in thread "main" javax.persistence.PersistenceException: No Persistence provider for EntityManager named WebApplication1PU: Provider named oracle.toplink.essentials.PersistenceProvider threw unexpected exception at create EntityManagerFactory:
oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException
Local Exception Stack:
Exception [TOPLINK-30005] (Oracle TopLink Essentials - 2.0.1 (Build b09d-fcs (12/06/2007))): oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException
Exception Description: An exception was thrown while searching for persistence archives with ClassLoader: sun.misc.Launcher$AppClassLoader@f6a746
Internal Exception: Exception [TOPLINK-30004] (Oracle TopLink Essentials - 2.0.1 (Build b09d-fcs (12/06/2007))): oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException
Exception Description: An exception was thrown while processing persistence.xml from URL: file:/C:/Users/m-takayashiki/Documents/NetBeansProjects/NoJSF/build/web/WEB-INF/classes/
Internal Exception:
(1. cvc-complex-type.3.1: Value '2.0' of attribute 'version' of element 'persistence' is not valid with respect to the corresponding attribute use. Attribute 'version' has a fixed value of '1.0'.)
at oracle.toplink.essentials.exceptions.PersistenceUnitLoadingException.exceptionSearchingForPersistenceResources(PersistenceUnitLoadingException.java:143)
at oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider.createEntityManagerFactory(EntityManagerFactoryProvider.java:169)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:110)
at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:83)
at local.test.tmp.Tmp.main(Tmp.java:24)
更新 3
经过一些研究,发现版本号需要符合 1.0,所以我应用了修复并得到了新的错误。
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" 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_1_0.xsd">
<persistence-unit name="NoJSFPU" transaction-type="JTA">
<provider>oracle.toplink.essentials.PersistenceProvider</provider>
<jta-data-source>masatoJNDI</jta-data-source>
<class>local.test.session.Addresses</class>
<class>local.test.session.Users</class>
<properties>
<property name="toplink.jdbc.url" value="jdbc:mysql://localhost:3306/mytest"/>
<property name="toplink.jdbc.driver" value="com.mysql.jdbc.Driver"/>
<property name="toplink.jdbc.user" value="masato" />
<property name="toplink.jdbc.password" value="mocha123" />
</properties>
</persistence-unit>
</persistence>
这很奇怪,因为我已经在上面的 persistence.xml 中指定了类:(
Exception in thread "main" javax.persistence.PersistenceException: Exception [TOPLINK-7060]
(Oracle TopLink Essentials - 2.0.1 (Build b09d-fcs (12/06/2007))): oracle.toplink.essentials.exceptions.ValidationException
Exception Description: Cannot acquire data source [masatoJNDI].
Internal Exception: javax.naming.NoInitialContextException: Need to specify class name in
environment or system property, or as an applet parameter, or in an application resource
file: java.naming.factory.initial
更新 4
我不认为这被称为“已解决”,但经过长时间的尝试,我决定只在 Web 应用程序中运行我的测试代码,而不是从 netbean 单独运行。我必须自己创建 web.xml,因为 GlassFish 不提供它。(我看到 sun-web.xml 但它不是替换)然后创建 servlet,在 web.xml 中定义映射并将我的测试代码片段添加到 servlet 并在浏览器上尝试。它工作,成功地从数据库中获取数据。
我想知道当我尝试从 Netbean 运行 Tmp.java (我的测试文件)时它不起作用的原因是什么......