mysql - 通过 hibernate 将 tomcat 容器上的 web 应用程序连接到 mysql 容器

Question

我正在尝试将我的网络应用程序从 Windows(使用 xampp for apache+mysql)移植到 ubuntu(使用 docker 容器，所以我有两个容器:一个带有 tomcat，另一个带有 mysql。它们是链接的).

与此相关question ，我无法访问我的 sql 容器。它是从 this image 创建的.

Tomcat 容器是从官方 tomcat:8.0 镜像创建的。

这两个容器通过创建的桥接 docker 网络链接。

这是一个网络应用程序，提供登录+注册服务，检查用户在数据库中的存在。

我不得不说在 Windows 上一切正常。

这是我的 hibernate.cfg 文件:

<!DOCTYPE hibernate-configuration PUBLIC
    "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
    "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <session-factory>

<!-- queste configurazioni sono per il testing in locale  -->
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost:49162/AT_DB</property>

<property name="hibernate.connection.username">root</property>
<property name="connection.password">lxit</property>

<!-- JDBC connection pool (use the built-in) -->
<property name="connection.pool_size">1</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- Enable Hibernate's automatic session context management -->
<property name="current_session_context_class">thread</property>
<!-- Disable the second-level cache -->
<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

<property name="show_sql">false</property>
<!--<property name="hibernate.hbm2ddl.auto">create-drop</property>  se al posto di update metto create, mi cancella il db e lo rifa -->
<property name="hbm2ddl.auto">update</property>
        <!-- Entity -->

<mapping class="com.ATBoscoCastellano.Entity.ClientUser" />
<mapping class="com.ATBoscoCastellano.Entity.GenericUser" />
<mapping class="com.ATBoscoCastellano.SessionManagement.SessionToken" />
<mapping class="com.ATBoscoCastellano.Entity.Post" />
<!-- <mapping class="it.boscus.StarFoods.entity.ExampleEmbeddableIDClass2" /> -->


    </session-factory>
</hibernate-configuration>

在我插入我的凭证后，我点击“登录”；然后有一个名为“UserSessionServlet”的 servlet 检查数据库中是否存在具有该凭据的用户；当我点击登录时出现错误，因为 UserSessionServlet 返回 http 500 错误。

[编辑] 在 tomcat 容器上，我看到日志告诉我:

16-Feb-2017 09:43:41.498 SEVERE [http-nio-8080-exec-19] org.apache.catalina.core.StandardWrapperValve.invoke Servlet.service() for servlet [com.ATBoscoCastellano.servlets.UserSessionServlet] in context with path [/AtApplicazione1] threw exception [Servlet execution threw an 
exception] with root cause
 java.lang.NoClassDefFoundError: Could not initialize class com.ATBoscoCastellano.Util.HibernateUtil.HibernateUtil
    at com.ATBoscoCastellano.Entity.GenericUser.checkIfUserExistsByEmail(GenericUser.java:198)
    at com.ATBoscoCastellano.Entity.ClientUser.validateCredentials(ClientUser.java:259)
    at com.ATBoscoCastellano.servlets.UserSessionServlet.doPost(UserSessionServlet.java:78)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:292)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:240)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:207)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:509)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1104)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:684)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1520)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1476)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)

但是所有这些类都存在于 opt/tomcat/webapps/AtApplicazione1/WEB-INF/classes/com/AtBoscoCastellano/some/paths 下。

我必须告诉我，我没有从官方镜像 (tomcat:8.0) 修改我的 tomcat 容器，所以我不知道它是否配置为 hibernate 。

我的war结构如下:三个文件夹(META-INF、WEB-INF、template)和一个文件(.DS_Store)。因为我的异常是:java.lang.NoClassDefFoundError: Could not initialize class com.ATBoscoCastellano.Util.HibernateUtil.HibernateUtil ，在 war 中，这个类在WEB-INF/classes/com/ATBoscoCastellano下/Util/HibernateUtil/...其中有HibernateUtil .class和.java。

当我在我的 tomcat 容器上运行 java/javac -version 时，它的输出是:

root@a26ff8018f3f:/opt/tomcat# java -version
java version "1.8.0_111"
Java(TM) SE Runtime Environment (build 1.8.0_111-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.111-b14, mixed mode)

root@a26ff8018f3f:/opt/tomcat# javac -version
javac "1.8.0_111"

[重新编辑]:在我的第一个请求中，catalina 日志显示 java.net.ConnectException: Connection refused；然后，根据第二个请求，它总是对我说同样的错误。

[编辑] 现在我正在使用一个新的 mysql 容器，名为 mysql-phpmyadmin 来自 this图像。我已将 tomcat 容器链接到这个(新)容器；如果我在 hibernate.cfg.xml 中指向 localhost:PORT_MYSQL/AT_DB --> 连接在 tomcat 日志中被拒绝。如果我指向 mysql-phpmyadmin:PORT/AT_DB，tomcat 日志显示:

17-Feb-2017 08:31:25.649 SEVERE [http-apr-8080-exec-2] org.apache.catalina.core.StandardWrapperValve.invoke Servlet.service() for servlet [com.ATBoscoCastellano.servlets.UserSessionServlet] in context with path [/AtApplicazione1] threw exception [Servlet execution threw an e
xception] with root cause
 java.sql.SQLException: null,  message from server: "Host '172.17.0.9' is not allowed to connect to this MySQL server"
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:959)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887)
    at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1038)
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2254)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2285)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2084)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:795)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)

我必须告诉你，在 mysql 容器的配置文件中，有 bind_address 0.0.0.0

Answer 1

我想我知道您为什么会收到此异常。您正在运行 2 个容器，

1. 数据库的mysql容器
2. Tomcat 容器

当然，你的异常是由于静态变量初始化异常，

public static final SessionFactory sessionFactory = buildSessionFactory();

此外，您的属性文件几乎没有问题，

1. connection.url 应该是 hibernate.connection.url
2. 您提到您的 mysql 主机名为 localhost，但它在另一个容器中运行。如果您将 mysql 容器命名为“mysql”，则应将其更改为“mysql”

---

java.net.ConnectException: Connection refused (Connection refused)
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:214)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:298)

清楚地表明你的任一个

1. Mysql 没有运行。通过从 sql 客户端(如 squirrel)建立连接进行检查。

2. Tomcat 容器无法连接到 mysql 容器。通过执行检查快速 ping

   docker exec tomcat ping mysql  
   

---

我花了一些时间来部署这个应用程序。我已经解决了你在这个问题中提出的问题。主要问题是无法从 tomcat 容器访问 mysql。此外，指定的端口也不正确。以下是hibernate.cfg.xml，

<!DOCTYPE hibernate-configuration PUBLIC
    "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
    "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <session-factory>

<!-- queste configurazioni sono per il testing in locale  -->
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://mysql:3306/AT_DB</property>

<property name="hibernate.connection.username">root</property>
<property name="connection.password">lxit</property>

 ....rest of configuration....      

    </session-factory>
</hibernate-configuration>

有如下几个问题，

17-Feb-2017 16:07:53.156 INFO [http-nio-8080-exec-1] org.hibernate.dialect.Dialect.<init> HHH000400: Using dialect: org.hibernate.dialect.MySQLDialect
17-Feb-2017 16:07:53.776 INFO [http-nio-8080-exec-1] org.hibernate.tool.schema.extract.internal.InformationExtractorJdbcDatabaseMetaDataImpl.processGetTableResults HHH000262: Table not found: ClientUser
17-Feb-2017 16:07:53.777 INFO [http-nio-8080-exec-1] org.hibernate.tool.schema.extract.internal.InformationExtractorJdbcDatabaseMetaDataImpl.processGetTableResults HHH000262: Table not found: ClientUser
17-Feb-2017 16:07:53.818 INFO [http-nio-8080-exec-1] org.hibernate.tool.schema.extract.internal.InformationExtractorJdbcDatabaseMetaDataImpl.processGetTableResults HHH000262: Table not found: Post
17-Feb-2017 16:07:53.819 INFO [http-nio-8080-exec-1] org.hibernate.tool.schema.extract.internal.InformationExtractorJdbcDatabaseMetaDataImpl.processGetTableResults HHH000262: Table not found: Post
17-Feb-2017 16:07:53.828 INFO [http-nio-8080-exec-1] org.hibernate.tool.schema.extract.internal.InformationExtractorJdbcDatabaseMetaDataImpl.processGetTableResults HHH000262: Table not found: SessionToken
17-Feb-2017 16:07:53.828 INFO [http-nio-8080-exec-1] org.hibernate.tool.schema.extract.internal.InformationExtractorJdbcDatabaseMetaDataImpl.processGetTableResults HHH000262: Table not found: SessionToken
17-Feb-2017 16:07:53.830 WARN [http-nio-8080-exec-1] org.hibernate.tool.schema.internal.ExceptionHandlerLoggedImpl.handleException GenerationTarget encountered exception accepting command : Unable to execut

但这些是由于 unix 区分大小写，这在 Windows 中可能不存在。其余的异常很容易解决。我按照 docker 命令运行，

 sudo docker run -ti --rm -p 8888:8080 -p 8009:8009 -v $(pwd):/usr/local/tomcat/webapps/ --name tomcat tomcat:9-jre8 bash

 sudo docker run -d --name mysql -p 49162:3306 -p 49161:80 -p 49160:22 lxitgto/mysql-phpmyadmin:v1

和其余的网络命令。