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JPA - 連接數據庫幾分鐘後超時

2014-03-01 180 views
1

我使用Netbeans和本地Glassfish服務器實例運行Web應用程序。一切工作都正常，但如果我將站點閒置幾分鐘，然後嘗試導航到需要數據庫操作的頁面，數據庫似乎超時。JPA - 連接數據庫幾分鐘後超時

我沒有在persistence.xml或其他任何地方更改任何特定的設置。一切都在默認設置下運行。

請注意，我連接的MySQL服務器不是我的服務器。我有寫權限單獨的數據庫，所以我不能更改任何全球MySQL配置文件或任何東西。

從棧跟蹤它看起來像一個eclipseLink問題，但我不知道如何去解決它。

INFO: Communication failure detected when attempting to perform read query outside of a transaction. Attempting to retry query. Error was: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.5.0.v20130507-3faac2b): org.eclipse.persistence.exceptions.DatabaseException 
Internal Exception: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed. 
Error Code: 0 
Call: SELECT Reg, Colour, EngineCC, FuelType, ImagePath, IsAvailable, Make, Model, Price, Transmission, Year FROM Vehicle WHERE ((((Make = ?) AND (Transmission = ?)) AND (Price < ?)) AND (IsAvailable = ?)) 
    bind => [4 parameters bound] 
Query: ReadAllQuery(referenceClass=Vehicle sql="SELECT Reg, Colour, EngineCC, FuelType, ImagePath, IsAvailable, Make, Model, Price, Transmission, Year FROM Vehicle WHERE ((((Make = ?) AND (Transmission = ?)) AND (Price < ?)) AND (IsAvailable = ?))"). 
WARNING: Local Exception Stack: 
Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.5.0.v20130507-3faac2b): org.eclipse.persistence.exceptions.DatabaseException 
Internal Exception: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed. 
Error Code: 0 
Call: SELECT Reg, Colour, EngineCC, FuelType, ImagePath, IsAvailable, Make, Model, Price, Transmission, Year FROM Vehicle WHERE ((((Make = ?) AND (Transmission = ?)) AND (Price < ?)) AND (IsAvailable = ?)) 
    bind => [4 parameters bound] 
Query: ReadAllQuery(referenceClass=Vehicle sql="SELECT Reg, Colour, EngineCC, FuelType, ImagePath, IsAvailable, Make, Model, Price, Transmission, Year FROM Vehicle WHERE ((((Make = ?) AND (Transmission = ?)) AND (Price < ?)) AND (IsAvailable = ?))") 
    at org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:340) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.processExceptionForCommError(DatabaseAccessor.java:1605) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:671) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeCall(DatabaseAccessor.java:558) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.basicExecuteCall(AbstractSession.java:1995) 
    at org.eclipse.persistence.sessions.server.ServerSession.executeCall(ServerSession.java:570) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:242) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:228) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeSelectCall(DatasourceCallQueryMechanism.java:299) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.selectAllRows(DatasourceCallQueryMechanism.java:694) 
    at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRowsFromTable(ExpressionQueryMechanism.java:2714) 
    at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRows(ExpressionQueryMechanism.java:2667) 
    at org.eclipse.persistence.queries.ReadAllQuery.executeObjectLevelReadQuery(ReadAllQuery.java:477) 
    at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:1155) 
    at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:899) 
    at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:1114) 
    at org.eclipse.persistence.queries.ReadAllQuery.execute(ReadAllQuery.java:402) 
    at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeInUnitOfWork(ObjectLevelReadQuery.java:1202) 
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.internalExecuteQuery(UnitOfWorkImpl.java:2894) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1797) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.retryQuery(AbstractSession.java:1867) 
    at org.eclipse.persistence.sessions.server.ClientSession.retryQuery(ClientSession.java:685) 
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.retryQuery(UnitOfWorkImpl.java:5532) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1833) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.retryQuery(AbstractSession.java:1867) 
    at org.eclipse.persistence.sessions.server.ClientSession.retryQuery(ClientSession.java:685) 
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.retryQuery(UnitOfWorkImpl.java:5532) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1833) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.retryQuery(AbstractSession.java:1867) 
    at org.eclipse.persistence.sessions.server.ClientSession.retryQuery(ClientSession.java:685) 
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.retryQuery(UnitOfWorkImpl.java:5532) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1833) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.retryQuery(AbstractSession.java:1867) 
    at org.eclipse.persistence.sessions.server.ClientSession.retryQuery(ClientSession.java:685) 
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.retryQuery(UnitOfWorkImpl.java:5532) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1833) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1779) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1744) 
    at org.eclipse.persistence.internal.jpa.QueryImpl.executeReadQuery(QueryImpl.java:258) 
    at org.eclipse.persistence.internal.jpa.QueryImpl.getResultList(QueryImpl.java:468) 
    at Servlet.SearchServlet.processRequest(SearchServlet.java:66) 
    at Servlet.SearchServlet.doPost(SearchServlet.java:120) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:707) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) 
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682) 
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318) 
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160) 
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734) 
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673) 
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99) 
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174) 
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357) 
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260) 
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188) 
    at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191) 
    at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168) 
    at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189) 
    at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114) 
    at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77) 
    at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838) 
    at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113) 
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115) 
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55) 
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135) 
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564) 
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544) 
    at java.lang.Thread.run(Thread.java:724) 
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed. 
    at sun.reflect.GeneratedConstructorAccessor135.newInstance(Unknown Source) 
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) 
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526) 
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:411) 
    at com.mysql.jdbc.Util.getInstance(Util.java:386) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1014) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:988) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:974) 
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919) 
    at com.mysql.jdbc.ConnectionImpl.throwConnectionClosedException(ConnectionImpl.java:1290) 
    at com.mysql.jdbc.ConnectionImpl.checkClosed(ConnectionImpl.java:1282) 
    at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4468) 
    at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4434) 
    at com.sun.gjc.spi.base.ConnectionHolder.prepareStatement(ConnectionHolder.java:514) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.prepareStatement(DatabaseAccessor.java:1551) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.prepareStatement(DatabaseAccessor.java:1500) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseCall.prepareStatement(DatabaseCall.java:778) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:619) 
    ... 68 more 
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure 
The last packet successfully received from the server was 303,413 milliseconds ago. The last packet sent successfully to the server was 1 milliseconds ago. 
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) 
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) 
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526) 
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:411) 
    at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1117) 
    at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3603) 
    at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3492) 
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4043) 
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2503) 
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2664) 
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2794) 
    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155) 
    at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2322) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeSelect(DatabaseAccessor.java:1002) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:641) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeCall(DatabaseAccessor.java:558) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.basicExecuteCall(AbstractSession.java:1995) 
    at org.eclipse.persistence.sessions.server.ServerSession.executeCall(ServerSession.java:570) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:242) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:228) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeSelectCall(DatasourceCallQueryMechanism.java:299) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.selectAllRows(DatasourceCallQueryMechanism.java:694) 
    at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRowsFromTable(ExpressionQueryMechanism.java:2714) 
    at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRows(ExpressionQueryMechanism.java:2667) 
    at org.eclipse.persistence.queries.ReadAllQuery.executeObjectLevelReadQuery(ReadAllQuery.java:477) 
    at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:1155) 
    at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:899) 
    at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:1114) 
    at org.eclipse.persistence.queries.ReadAllQuery.execute(ReadAllQuery.java:402) 
    at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeInUnitOfWork(ObjectLevelReadQuery.java:1202) 
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.internalExecuteQuery(UnitOfWorkImpl.java:2894) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1797) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1779) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1744) 
    at org.eclipse.persistence.internal.jpa.QueryImpl.executeReadQuery(QueryImpl.java:258) 
    at org.eclipse.persistence.internal.jpa.QueryImpl.getResultList(QueryImpl.java:468) 
    at Servlet.DisplayVehicles.processRequest(DisplayVehicles.java:35) 
    at Servlet.DisplayVehicles.doGet(DisplayVehicles.java:64) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:687) 
    ... 28 more 
Caused by: java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost. 
    at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3052) 
    at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3503) 
    ... 61 more 

WARNING: StandardWrapperValve[SearchServlet]: Servlet.service() for servlet SearchServlet threw exception 
java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost. 
    at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3052) 
    at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3503) 
    at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3492) 
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4043) 
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2503) 
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2664) 
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2794) 
    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155) 
    at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2322) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeSelect(DatabaseAccessor.java:1002) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:641) 
    at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeCall(DatabaseAccessor.java:558) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.basicExecuteCall(AbstractSession.java:1995) 
    at org.eclipse.persistence.sessions.server.ServerSession.executeCall(ServerSession.java:570) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:242) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:228) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeSelectCall(DatasourceCallQueryMechanism.java:299) 
    at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.selectAllRows(DatasourceCallQueryMechanism.java:694) 
    at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRowsFromTable(ExpressionQueryMechanism.java:2714) 
    at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRows(ExpressionQueryMechanism.java:2667) 
    at org.eclipse.persistence.queries.ReadAllQuery.executeObjectLevelReadQuery(ReadAllQuery.java:477) 
    at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:1155) 
    at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:899) 
    at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:1114) 
    at org.eclipse.persistence.queries.ReadAllQuery.execute(ReadAllQuery.java:402) 
    at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeInUnitOfWork(ObjectLevelReadQuery.java:1202) 
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.internalExecuteQuery(UnitOfWorkImpl.java:2894) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1797) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1779) 
    at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1744) 
    at org.eclipse.persistence.internal.jpa.QueryImpl.executeReadQuery(QueryImpl.java:258) 
    at org.eclipse.persistence.internal.jpa.QueryImpl.getResultList(QueryImpl.java:468) 
    at Servlet.DisplayVehicles.processRequest(DisplayVehicles.java:35) 
    at Servlet.DisplayVehicles.doGet(DisplayVehicles.java:64) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:687) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) 
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682) 
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318) 
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160) 
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734) 
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673) 
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99) 
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174) 
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357) 
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260) 
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188) 
    at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191) 
    at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168) 
    at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189) 
    at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114) 
    at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77) 
    at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838) 
    at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113) 
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115) 
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55) 
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135) 
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564) 
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544) 
    at java.lang.Thread.run(Thread.java:724)

使用數據庫查詢一個典型的servlet：

@WebServlet(name = "DisplayVehicles", urlPatterns = {"/Browse"}) 
public class DisplayVehicles extends HttpServlet { 

    @PersistenceUnit 
    private EntityManagerFactory emf; 

    /** Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods. 
    * @param request servlet request 
    * @param response servlet response 
    */ 
    protected void processRequest(HttpServletRequest request, HttpServletResponse response) 
    throws ServletException, IOException { 
     assert emf != null; //Make sure injection went through correctly. 
     EntityManager em = null; 
     try { 
      em = emf.createEntityManager(); 
      //query for all the cars in database 

      List images = em.createQuery("SELECT v FROM Vehicle v WHERE v.imagePath IS NOT NULL AND v.isAvailable=1").getResultList();   
      request.setAttribute("searchResultsList",images); 

      //Forward to the jsp page for rendering 
      request.getRequestDispatcher("Browse.jsp").forward(request, response); 
     } catch (Exception ex) { 
      throw new ServletException(ex); 
     } finally { 
      //close the em to release any resources held up by the persistence provider 
      if(em != null) { 
       em.close(); 
      } 
     } 

}

來源

2014-03-01 karoma

+0

你有沒有公開的會議？如果是，請嘗試在查詢之前打開新會話，然後關閉它。 – pL4Gu33

+0

我根本沒有專門使用會話。我向OP中添加了一個servlet類的示例。我應該使用會話嗎？ – karoma

+0

我認爲你會遇到死亡的連接。代碼看起來沒問題 – pL4Gu33

回答

0

基礎上MySQLNonTransientConnectionException我會打賭，MySQL的WAIT_TIMEOUT的DB變量是很短的，你正在失去連接EM正試圖訪問。解決這個問題的一個方法是使用Connection pool on your Glassfish server並讓它控制DBConnections而不是EclipseLink。作爲一個很好的副作用，它應該更具有預見性。

來源

2014-03-01 17:07:24 jeremyjjbrown

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