JavaEE7-动手实验教程——无法加载数据库？

Question

我正在关注Java EE7-hands 实验室here 上的教程。我按照那里提供的说明设置了我的WildFly Application server。一切正常。教程 zip 附带示例数据和用于初始化数据源的 sql load scripts。如果persistence.xml 中没有提供数据源，WildFly 将提供一个default data-source，如教程中所述。

在tutorial link 的第 3 步结束时，我的屏幕截图如下所示：

但预期的结果（根据tutorial link：图 12）是这样的：

区别在于“在影院放映电影！”就我而言，“在 7 个影院放映 20 部电影！”在预期的一个。 用于显示这些数字的 JSF 模板进行 EJB 调用，从数据源获取数据。看着这个，我认为我的数据源没有初始化。但我不知道为什么，因为我逐字遵循教程。我也很难解决这个问题。

提前感谢您的帮助

编辑

服务器日志显示Unable to determine H2 database version, certain features may not work.

2014-10-02 18:02:50,167 INFO  [org.hibernate.Version] (ServerService Thread Pool -- 50) HHH000412: Hibernate Core {4.3.5.Final}
2014-10-02 18:02:50,170 INFO  [org.hibernate.cfg.Environment] (ServerService Thread Pool -- 50) HHH000206: hibernate.properties not found
2014-10-02 18:02:50,172 INFO  [org.hibernate.cfg.Environment] (ServerService Thread Pool -- 50) HHH000021: Bytecode provider name : javassist
2014-10-02 18:02:50,330 INFO  [org.jboss.ws.common.management] (MSC service thread 1-6) JBWS022052: Starting JBoss Web Services - Stack CXF Server 4.2.4.Final
2014-10-02 18:02:50,491 INFO  [org.jboss.as.jpa] (ServerService Thread Pool -- 50) JBAS011409: Starting Persistence Unit (phase 2 of 2) Service 'movieplex7.war#movieplex7PU'
2014-10-02 18:02:50,641 INFO  [org.hibernate.annotations.common.Version] (ServerService Thread Pool -- 50) HCANN000001: Hibernate Commons Annotations {4.0.4.Final}
2014-10-02 18:02:50,875 INFO  [org.hibernate.dialect.Dialect] (ServerService Thread Pool -- 50) HHH000400: Using dialect: org.hibernate.dialect.H2Dialect
2014-10-02 18:02:50,883 WARN  [org.hibernate.dialect.H2Dialect] (ServerService Thread Pool -- 50) HHH000431: Unable to determine H2 database version, certain features may not work
2014-10-02 18:02:50,922 INFO  [org.hibernate.hql.internal.ast.ASTQueryTranslatorFactory] (ServerService Thread Pool -- 50) HHH000397: Using ASTQueryTranslatorFactory
2014-10-02 18:02:51,047 INFO  [org.hibernate.dialect.Dialect] (ServerService Thread Pool -- 50) HHH000400: Using dialect: org.hibernate.dialect.H2Dialect
2014-10-02 18:02:51,048 WARN  [org.hibernate.dialect.H2Dialect] (ServerService Thread Pool -- 50) HHH000431: Unable to determine H2 database version, certain features may not work
2014-10-02 18:02:51,055 WARN  [org.hibernate.jpa.internal.schemagen.GenerationTargetToDatabase] (ServerService Thread Pool -- 50) Unable to execute JPA schema generation drop command [DROP TABLE SALES]
2014-10-02 18:02:51,055 WARN  [org.hibernate.jpa.internal.schemagen.GenerationTargetToDatabase] (ServerService Thread Pool -- 50) Unable to execute JPA schema generation drop command [DROP TABLE POINTS]
2014-10-02 18:02:51,055 WARN  [org.hibernate.jpa.internal.schemagen.GenerationTargetToDatabase] (ServerService Thread Pool -- 50) Unable to execute JPA schema generation drop command [DROP TABLE SHOW_TIMING]
2014-10-02 18:02:51,055 WARN  [org.hibernate.jpa.internal.schemagen.GenerationTargetToDatabase] (ServerService Thread Pool -- 50) Unable to execute JPA schema generation drop command [DROP TABLE MOVIE]
2014-10-02 18:02:51,056 WARN  [org.hibernate.jpa.internal.schemagen.GenerationTargetToDatabase] (ServerService Thread Pool -- 50) Unable to execute JPA schema generation drop command [DROP TABLE TIMESLOT]
2014-10-02 18:02:51,056 WARN  [org.hibernate.jpa.internal.schemagen.GenerationTargetToDatabase] (ServerService Thread Pool -- 50) Unable to execute JPA schema generation drop command [DROP TABLE THEATER]
2014-10-02 18:02:51,250 INFO  [javax.enterprise.resource.webcontainer.jsf.config] (MSC service thread 1-8) Initializing Mojarra 2.2.6-jbossorg-4 20140501-1134 for context '/movieplex7'
2014-10-02 18:02:51,867 INFO  [org.wildfly.extension.undertow] (MSC service thread 1-8) JBAS017534: Registered web context: /movieplex7
2014-10-02 18:02:51,905 INFO  [org.jboss.as.server] (ServerService Thread Pool -- 28) JBAS018559: Deployed "movieplex7.war" (runtime-name : "movieplex7.war")
2014-10-02 18:02:51,910 INFO  [org.jboss.as] (Controller Boot Thread) JBAS015961: Http management interface listening on http://127.0.0.1:9990/management
2014-10-02 18:02:51,911 INFO  [org.jboss.as] (Controller Boot Thread) JBAS015951: Admin console listening on http://127.0.0.1:9990
2014-10-02 18:02:51,911 INFO  [org.jboss.as] (Controller Boot Thread) JBAS015874: WildFly 8.1.0.Final "Kenny" started in 5525ms - Started 256 of 310 services (91 services are lazy, passive or on-demand)

我还在 github repo 中提出了一个问题： https://github.com/javaee-samples/javaee7-hol/issues/17#issuecomment-57561731

Answer 1

所以我得到了应用程序，并尝试运行它（Netbeans、Wildfly-8.1）。它根本没有运行。找不到数据源的问题。所以（Wildfly 启动时）我去了管理控制台localhost:9990 并输入了我的凭据。在控制台中，选择 [Configuration] 选项卡，然后选择 [Datasources]。没有默认数据源。有一个 java:jboss/datasources/ExampleDS 作为预配置的数据源。所以在persistence.xml 中，我将数据源更改为那个，它起作用了。仅供参考，我从下载的解决方案目录中运行了 movieplex7

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这是我对整个项目所做的唯一更改。刚刚把数据源的jndi名字改成<jta-data-source>java:jboss/datasources/ExampleDS</jta-data-source>

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编辑

所以@ArunGupta 是正确的。在应用程序中，在persistence.xml 中有这条注释掉的行

<!--<jta-data-source>java:comp/DefaultDataSource</jta-data-source>-->

我以为我必须取消注释。通过取消注释它，这就是导致它最初不起作用的原因。所以我把它注释掉了，没有指定任何数据源，即java:jboss/datasources/ExampleDS，它按指定工作。所以你的问题似乎出在其他地方。

Answer 2

添加

<jta-data-source>java:jboss/datasources/ExampleDS</jta-data-source>

不应是必需的，因为 Java EE 7 定义了应自动获取的新默认数据源。

https://github.com/javaee-samples/javaee7-hol/issues/17 也在讨论这个问题。