Salve,
sto sviluppando un applicativo che deve connettersi ad un database tramite IDE Netbeans 6.1.
Fra le tante classi ne ho scritto una in particolare che serve per la connessione al database
Tale metodo, che poi altro non è che il costruttore dell'oggetto, fino a ieri funzionava tranquillamente. Oggi, continuando con lo sviluppo dell'applicazione, mi esce fuori questa eccezione relativa all'istruzione DriverManager.getConnection(....)codice:public DBCommunicator() throws ClassNotFoundException, SQLException{ Class.forName("com.mysql.jdbc.Driver"); connection = DriverManager.getConnection("jdbc:mysql://localhost/nomeDB" , "utente" , "passw"); statement=connection.createStatement(); }
Cosa è successo al metodo? Come ci si muove in queste circostanze? grazie in anticipo a tutti coloro che mi daranno il proprio contributo.codice:com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception: ** BEGIN NESTED EXCEPTION ** java.net.SocketException MESSAGE: java.net.ConnectException: Connection refused: connect STACKTRACE: java.net.SocketException: java.net.ConnectException: Connection refused: connect at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:156) at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:284) at com.mysql.jdbc.Connection.createNewIO(Connection.java:2555) at com.mysql.jdbc.Connection.<init>(Connection.java:1485) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:266) at java.sql.DriverManager.getConnection(DriverManager.java:582) at java.sql.DriverManager.getConnection(DriverManager.java:185) at dbutility.DBCommunicator.<init>(DBCommunicator.java:21) at dbutility.DBSelect.<init>(DBSelect.java:17) at operation.OperazioniSuUtenti.searchUtente(OperazioniSuUtenti.java:48) at myApplication.RemoteInterfaceImplementation.selectUser(RemoteInterfaceImplementation.java:104) at smsnoticeserver.RemoteInterfaceImplementation_Skel.dispatch(Unknown Source) at sun.rmi.server.UnicastServerRef.oldDispatch(UnicastServerRef.java:386) at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:250) at sun.rmi.transport.Transport$1.run(Transport.java:159) at java.security.AccessController.doPrivileged(Native Method) at sun.rmi.transport.Transport.serviceCall(Transport.java:155) at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:535) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:790) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:649) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:619) ** END NESTED EXCEPTION ** Last packet sent to the server was 5 ms ago. at com.mysql.jdbc.Connection.createNewIO(Connection.java:2621) at com.mysql.jdbc.Connection.<init>(Connection.java:1485) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:266) at java.sql.DriverManager.getConnection(DriverManager.java:582) at java.sql.DriverManager.getConnection(DriverManager.java:185) at dbutility.DBCommunicator.<init>(DBCommunicator.java:21) at dbutility.DBSelect.<init>(DBSelect.java:17) at operation.OperazioniSuUtenti.searchUtente(OperazioniSuUtenti.java:48) at myApplication.RemoteInterfaceImplementation.selectUser(RemoteInterfaceImplementation.java:104) at myApplication.RemoteInterfaceImplementation_Skel.dispatch(Unknown Source) at sun.rmi.server.UnicastServerRef.oldDispatch(UnicastServerRef.java:386) at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:250) at sun.rmi.transport.Transport$1.run(Transport.java:159) at java.security.AccessController.doPrivileged(Native Method) at sun.rmi.transport.Transport.serviceCall(Transport.java:155) at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:535) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:790) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:649) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:619) at sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(StreamRemoteCall.java:255) at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:233) at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:359) at myApplication.RemoteInterfaceImplementation_Stub.selectUser(Unknown Source) at myApplicationClient.Core.selectUser(Core.java:59) at gui.Login.OkActionPerformed(Login.java:165) at gui.Login.access$200(Login.java:22) at gui.Login$3.actionPerformed(Login.java:88) at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995) at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318) at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387) at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242) at javax.swing.plaf.basic.BasicButtonListener$Actions.actionPerformed(BasicButtonListener.java:287) at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1636) at javax.swing.JComponent.processKeyBinding(JComponent.java:2849) at javax.swing.JComponent.processKeyBindings(JComponent.java:2884) at javax.swing.JComponent.processKeyEvent(JComponent.java:2812) at java.awt.Component.processEvent(Component.java:5911) at java.awt.Container.processEvent(Container.java:2023) at java.awt.Component.dispatchEventImpl(Component.java:4501) at java.awt.Container.dispatchEventImpl(Container.java:2081) at java.awt.Component.dispatchEvent(Component.java:4331) at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1848) at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:704) at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:969) at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:841) at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:668) at java.awt.Component.dispatchEventImpl(Component.java:4373) at java.awt.Container.dispatchEventImpl(Container.java:2081) at java.awt.Window.dispatchEventImpl(Window.java:2458) at java.awt.Component.dispatchEvent(Component.java:4331) at java.awt.EventQueue.dispatchEvent(EventQueue.java:599) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161) at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
Ciao
Rispondi quotando