访问远程数据库

Question

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.lang.reflect.Constructor.newInstance(Constructor.java:423)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:377)

at com.mysql.jdbc.Util.getInstance(Util.java:360)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:956)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:935)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:924)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:870)

at com.mysql.jdbc.ConnectionImpl.throwConnectionClosedException(ConnectionImpl.java:1232)

at com.mysql.jdbc.ConnectionImpl.checkClosed(ConnectionImpl.java:1225)

at com.mysql.jdbc.ConnectionImpl.createStatement(ConnectionImpl.java:2417)

at com.mysql.jdbc.ConnectionImpl.createStatement(ConnectionImpl.java:2401)

at productDao.query(productDao.java:25)

at Servlet.doGet(Servlet.java:41)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:474)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)

at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)

at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:495)

at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)

at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:767)

at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1347)

at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)

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)

at java.lang.Thread.run(Thread.java:745)

Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 1,773,679 milliseconds ago.  The last packet sent successfully to the server was 1,773,684 milliseconds ago.

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.lang.reflect.Constructor.newInstance(Constructor.java:423)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:377)

at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1036)

at com.mysql.jdbc.MysqlIO.send(MysqlIO.java:3661)

at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2417)

at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2582)

at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2526)

at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2484)

at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1446)

at productDao.query(productDao.java:27)

... 25 more

Caused by: java.net.SocketException: Connection reset by peer: socket write error

at java.net.SocketOutputStream.socketWrite0(Native Method)

at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:109)

at java.net.SocketOutputStream.write(SocketOutputStream.java:153)

at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:82)

at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:140)

at com.mysql.jdbc.MysqlIO.send(MysqlIO.java:3643)

... 31 more

怎么回事？

Answer 1

你这个。。。。是不是远程的数据库没有打开哦？