com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
at com.mysql.jdbc.Util.getInstance(Util.java:387)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:898)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:887)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:862)
at com.mysql.jdbc.ConnectionImpl.throwConnectionClosedException(ConnectionImpl.java:1237)
at com.mysql.jdbc.ConnectionImpl.checkClosed(ConnectionImpl.java:1232)
at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4131)
at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4100)
at dao.impl.UserLoginDaoImpl.checkLogin(UserLoginDaoImpl.java:18)
at MyServlet.LoginServlet.doPost(LoginServlet.java:65)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:218)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:442)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1082)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:623)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)java
1 public class DBUtils { 2 static Connection con; 3 //讀取配置文件 4 static{ 5 Properties ps = new Properties(); 6 //不須要寫後綴名 7 ResourceBundle rundle = ResourceBundle.getBundle("db"); 8 String driver = rundle.getString("driver"); 9 String url = rundle.getString("url"); 10 String user = rundle.getString("username"); 11 String password = rundle.getString("password"); 12 13 try { 14 //加載數據庫驅動 15 Class.forName(driver); 16 } catch (ClassNotFoundException e) { 17 // TODO Auto-generated catch block 18 e.printStackTrace(); 19 } 20 try { 21 //數據庫鏈接 22 con = DriverManager.getConnection(url, user, password); 23 } catch (SQLException e) { 24 // TODO Auto-generated catch block 25 e.printStackTrace(); 26 } 27 28 } 29 public static Connection getconnection(){ 30 return con; 31 } 32 }
致使了數據庫鏈接只建立了一次,等我調用con.close()後,再次獲取數據庫鏈接就不存在了mysql
當我把靜態塊中的內容移動到獲取數據庫鏈接的方法裏(讓它每次調用方法的時候就建立一次鏈接),終於不報錯了,搞定!!!!web
1 public class DBUtils { 2 static Connection con; 3 //讀取配置文件 4 public static Connection getconnection(){ 5 Properties ps = new Properties(); 6 //不須要寫後綴名 7 ResourceBundle rundle = ResourceBundle.getBundle("db"); 8 String driver = rundle.getString("driver"); 9 String url = rundle.getString("url"); 10 String user = rundle.getString("username"); 11 String password = rundle.getString("password"); 12 13 try { 14 //加載數據庫驅動 15 Class.forName(driver); 16 } catch (ClassNotFoundException e) { 17 // TODO Auto-generated catch block 18 e.printStackTrace(); 19 } 20 try { 21 //數據庫鏈接 22 con = DriverManager.getConnection(url, user, password); 23 } catch (SQLException e) { 24 // TODO Auto-generated catch block 25 e.printStackTrace(); 26 } 27 return con; 28 } 29 }