嵌入式 Derby DB 可与多个客户端一起访问

Question

我编写基于 Java SE 8 的桌面应用程序。它得到了与我的应用程序一起提供的 Derby DB (v10.13.1.1)。我使用 Hibernate ORM 框架 (v5.2.10.Final) 与 DB 进行通信，并使用 Spring 框架 (spring-orm @ v4.3.7.RELEASE)，这也有助于它。

如果我一次将我的应用程序作为一个实例运行，一切都很好——数据库不会导致任何问题。但是如果我创建应用程序的多个实例，或者同时使用数据库客户端 DBeaver 访问数据库，则会导致以下异常：

[AWT-EventQueue-0] DEBUG (124 : 2017-07-28 22:14:57,245) org.hibernate.engine.jdbc.spi.SqlExceptionHelper  - Unable to acquire JDBC Connection [n/a]
java.sql.SQLException: Failed to start database 'M_Vezelis_Draw_DB_1_6v.db' with class loader sun.misc.Launcher$AppClassLoader@73d16e93, see the next exception for details.
    at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
    at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
    at org.apache.derby.impl.jdbc.Util.seeNextException(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection.bootDatabase(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection.<init>(Unknown Source)
    at org.apache.derby.jdbc.InternalDriver$1.run(Unknown Source)
    at org.apache.derby.jdbc.InternalDriver$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.jdbc.InternalDriver.getNewEmbedConnection(Unknown Source)
    at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source)
    at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source)
    at org.apache.derby.jdbc.AutoloadedDriver.connect(Unknown Source)
    at java.sql.DriverManager.getConnection(DriverManager.java:664)
    at java.sql.DriverManager.getConnection(DriverManager.java:208)
    at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriverManager(DriverManagerDataSource.java:153)
    at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriver(DriverManagerDataSource.java:144)
    at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnectionFromDriver(AbstractDriverBasedDataSource.java:196)
    at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnection(AbstractDriverBasedDataSource.java:159)
    at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:122)
    at org.hibernate.internal.NonContextualJdbcConnectionAccess.obtainConnection(NonContextualJdbcConnectionAccess.java:35)
    at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.acquireConnectionIfNeeded(LogicalConnectionManagedImpl.java:115)
    at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.getPhysicalConnection(LogicalConnectionManagedImpl.java:145)
    at org.hibernate.internal.SessionImpl.connection(SessionImpl.java:521)
    at org.springframework.orm.hibernate5.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:448)
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:373)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:447)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:277)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213)
    at com.sun.proxy.$Proxy33.getProjectDetails(Unknown Source)
    at com.mindaugas.vezelis.gui.MainGUI$4.actionPerformed(MainGUI.java:415)
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
    at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
    at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
    at javax.swing.AbstractButton.doClick(AbstractButton.java:376)
    at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:833)
    at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:877)
    at java.awt.Component.processMouseEvent(Component.java:6533)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
    at java.awt.Component.processEvent(Component.java:6298)
    at java.awt.Container.processEvent(Container.java:2236)
    at java.awt.Component.dispatchEventImpl(Component.java:4889)
    at java.awt.Container.dispatchEventImpl(Container.java:2294)
    at java.awt.Component.dispatchEvent(Component.java:4711)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4888)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4525)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4466)
    at java.awt.Container.dispatchEventImpl(Container.java:2280)
    at java.awt.Window.dispatchEventImpl(Window.java:2746)
    at java.awt.Component.dispatchEvent(Component.java:4711)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
    at java.awt.EventQueue.access$500(EventQueue.java:97)
    at java.awt.EventQueue$3.run(EventQueue.java:709)
    at java.awt.EventQueue$3.run(EventQueue.java:703)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:90)
    at java.awt.EventQueue$4.run(EventQueue.java:731)
    at java.awt.EventQueue$4.run(EventQueue.java:729)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
Caused by: ERROR XJ040: Failed to start database 'M_Vezelis_Draw_DB_1_6v.db' with class loader sun.misc.Launcher$AppClassLoader@73d16e93, see the next exception for details.
    at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
    at org.apache.derby.impl.jdbc.SQLExceptionFactory.wrapArgsForTransportAcrossDRDA(Unknown Source)
    ... 70 more
Caused by: ERROR XSDB6: Another instance of Derby may have already booted the database F:\Aristotelis\J-A-V-A\Java\M-Vezelis-Draw\M_Vezelis_Draw_DB_1_6v.db.
    at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
    at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
    at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.privGetJBMSLockOnDB(Unknown Source)
    at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.getJBMSLockOnDB(Unknown Source)
    at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.FileMonitor.startModule(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.store.raw.RawStore$6.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.impl.store.raw.RawStore.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.store.raw.RawStore.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.FileMonitor.startModule(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.store.access.RAMAccessManager$5.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.impl.store.access.RAMAccessManager.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.store.access.RAMAccessManager.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.FileMonitor.startModule(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.db.BasicDatabase$5.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.impl.db.BasicDatabase.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.db.BasicDatabase.bootStore(Unknown Source)
    at org.apache.derby.impl.db.BasicDatabase.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.bootService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startProviderService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.findProviderAndStartService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startPersistentService(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.startPersistentService(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection$4.run(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection$4.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.impl.jdbc.EmbedConnection.startPersistentService(Unknown Source)
    ... 67 more
[AWT-EventQueue-0] WARN  (129 : 2017-07-28 22:14:57,246) org.hibernate.engine.jdbc.spi.SqlExceptionHelper  - SQL Error: 40000, SQLState: XJ040
[AWT-EventQueue-0] ERROR (131 : 2017-07-28 22:14:57,247) org.hibernate.engine.jdbc.spi.SqlExceptionHelper  - Failed to start database 'M_Vezelis_Draw_DB_1_6v.db' with class loader sun.misc.Launcher$AppClassLoader@73d16e93, see the next exception for details.
[AWT-EventQueue-0] WARN  (129 : 2017-07-28 22:14:57,247) org.hibernate.engine.jdbc.spi.SqlExceptionHelper  - SQL Error: 45000, SQLState: XSDB6
[AWT-EventQueue-0] ERROR (131 : 2017-07-28 22:14:57,247) org.hibernate.engine.jdbc.spi.SqlExceptionHelper  - Another instance of Derby may have already booted the database F:\Aristotelis\J-A-V-A\Java\M-Vezelis-Draw\M_Vezelis_Draw_DB_1_6v.db.
Exception in thread "AWT-EventQueue-0" org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is org.hibernate.exception.GenericJDBCException: Unable to acquire JDBC Connection
    at org.springframework.orm.hibernate5.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:542)
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:373)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:447)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:277)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213)
    at com.sun.proxy.$Proxy33.getProjectDetails(Unknown Source)
    at com.mindaugas.vezelis.gui.MainGUI$4.actionPerformed(MainGUI.java:415)
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
    at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
    at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
    at javax.swing.AbstractButton.doClick(AbstractButton.java:376)
    at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:833)
    at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:877)
    at java.awt.Component.processMouseEvent(Component.java:6533)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
    at java.awt.Component.processEvent(Component.java:6298)
    at java.awt.Container.processEvent(Container.java:2236)
    at java.awt.Component.dispatchEventImpl(Component.java:4889)
    at java.awt.Container.dispatchEventImpl(Container.java:2294)
    at java.awt.Component.dispatchEvent(Component.java:4711)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4888)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4525)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4466)
    at java.awt.Container.dispatchEventImpl(Container.java:2280)
    at java.awt.Window.dispatchEventImpl(Window.java:2746)
    at java.awt.Component.dispatchEvent(Component.java:4711)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
    at java.awt.EventQueue.access$500(EventQueue.java:97)
    at java.awt.EventQueue$3.run(EventQueue.java:709)
    at java.awt.EventQueue$3.run(EventQueue.java:703)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:90)
    at java.awt.EventQueue$4.run(EventQueue.java:731)
    at java.awt.EventQueue$4.run(EventQueue.java:729)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
Caused by: org.hibernate.exception.GenericJDBCException: Unable to acquire JDBC Connection
    at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:47)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:111)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:97)
    at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.acquireConnectionIfNeeded(LogicalConnectionManagedImpl.java:118)
    at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.getPhysicalConnection(LogicalConnectionManagedImpl.java:145)
    at org.hibernate.internal.SessionImpl.connection(SessionImpl.java:521)
    at org.springframework.orm.hibernate5.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:448)
    ... 46 more
Caused by: java.sql.SQLException: Failed to start database 'M_Vezelis_Draw_DB_1_6v.db' with class loader sun.misc.Launcher$AppClassLoader@73d16e93, see the next exception for details.
    at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
    at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
    at org.apache.derby.impl.jdbc.Util.seeNextException(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection.bootDatabase(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection.<init>(Unknown Source)
    at org.apache.derby.jdbc.InternalDriver$1.run(Unknown Source)
    at org.apache.derby.jdbc.InternalDriver$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.jdbc.InternalDriver.getNewEmbedConnection(Unknown Source)
    at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source)
    at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source)
    at org.apache.derby.jdbc.AutoloadedDriver.connect(Unknown Source)
    at java.sql.DriverManager.getConnection(DriverManager.java:664)
    at java.sql.DriverManager.getConnection(DriverManager.java:208)
    at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriverManager(DriverManagerDataSource.java:153)
    at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriver(DriverManagerDataSource.java:144)
    at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnectionFromDriver(AbstractDriverBasedDataSource.java:196)
    at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnection(AbstractDriverBasedDataSource.java:159)
    at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:122)
    at org.hibernate.internal.NonContextualJdbcConnectionAccess.obtainConnection(NonContextualJdbcConnectionAccess.java:35)
    at org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.acquireConnectionIfNeeded(LogicalConnectionManagedImpl.java:115)
    ... 49 more
Caused by: ERROR XJ040: Failed to start database 'M_Vezelis_Draw_DB_1_6v.db' with class loader sun.misc.Launcher$AppClassLoader@73d16e93, see the next exception for details.
    at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
    at org.apache.derby.impl.jdbc.SQLExceptionFactory.wrapArgsForTransportAcrossDRDA(Unknown Source)
    ... 70 more
Caused by: ERROR XSDB6: Another instance of Derby may have already booted the database F:\Aristotelis\J-A-V-A\Java\M-Vezelis-Draw\M_Vezelis_Draw_DB_1_6v.db.
    at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
    at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
    at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.privGetJBMSLockOnDB(Unknown Source)
    at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.getJBMSLockOnDB(Unknown Source)
    at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.FileMonitor.startModule(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.store.raw.RawStore$6.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.impl.store.raw.RawStore.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.store.raw.RawStore.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.FileMonitor.startModule(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.store.access.RAMAccessManager$5.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.impl.store.access.RAMAccessManager.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.store.access.RAMAccessManager.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.FileMonitor.startModule(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.db.BasicDatabase$5.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.impl.db.BasicDatabase.bootServiceModule(Unknown Source)
    at org.apache.derby.impl.db.BasicDatabase.bootStore(Unknown Source)
    at org.apache.derby.impl.db.BasicDatabase.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
    at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.bootService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startProviderService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.findProviderAndStartService(Unknown Source)
    at org.apache.derby.impl.services.monitor.BaseMonitor.startPersistentService(Unknown Source)
    at org.apache.derby.iapi.services.monitor.Monitor.startPersistentService(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection$4.run(Unknown Source)
    at org.apache.derby.impl.jdbc.EmbedConnection$4.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.apache.derby.impl.jdbc.EmbedConnection.startPersistentService(Unknown Source)
    ... 67 more

异常的原因是：

Caused by: ERROR XSDB6: Another instance of Derby may have already booted the database

因此，DB 连接设置为嵌入，因为 DB 被用作嵌入到应用程序中。 什么是变通方法？

• 是否应将数据库设置为客户的服务提供者？
• 任何配置（DB 与 Hibernate 和 Spring）？

在配置与数据库的连接时，嵌入式方式可以顺利设置。而服务器类型总是以故障告终，这意味着通信被拒绝。

Answer 1

您不能在多个 JVM 之间共享 Derby DB 文件。第一个创建或连接到现有数据库的 JVM 会将文件锁定到自己，这样就不会发生数据损坏。

你有两个选择：

• 仅将您的数据库嵌入到驻留在单个 JVM 端的一个应用程序中，从而公开更高级别的 API 以通过 REST 或事件总线（或两者）使用它
• 启动Derby as a server，然后架构如下：

第二种方法可能更容易实现（更少的编码），JDBC 或 Hibernate 的 URL 看起来像 jdbc:derby://localhost:1527/derbyDB 当然，您需要先创建数据库，为此您需要将一次 与jdbc:derby://localhost:1527/derbyDB?create=true 连接。您不应该在 Hibernate 池中使用 `create=true。只需这样做：

try (Connection c = DriverManager.getConnection("jdbc:derby:derbyDB;create=true")) {
    System.out.println("Database created: "+c);
} catch (SQLException e) {
    e.printStackTrace(); //adapt it to your logging/error processing
}

上面的代码打印如下：

Database created: org.apache.derby.impl.jdbc.EmbedConnection@105374791 (XID = 167), (SESSIONID = 1), (DATABASE = derbyDB), (DRDAID = null) 

第一种方法，使用单个嵌入式应用程序和外部界面，可以让您更好地控制资源和访问。如果您追求效率/速度，那么花费的时间可能非常值得。

话虽如此，如果单个嵌入式 Derby 还不够，开发人员通常会寻找其他选项，例如PostgreSQL。甚至“DB2 Express C”也可以作为您的应用程序附带的选项。这真的取决于用例。