java connecting to mysql database fails -


i creating vaadin web application using tomcat , having external database on server. not able connect external database no matter what. have created new pure java project using j2se jre 1.6 , trying connect database connection still fails. downloaded mysql driver , copied ~/library/java/extensions , added/removed build path , still nothing changed. have firewall off , dont know else do. believe code correct, anyway:

string host = "jdbc:mysql://db.host.sk:3306/mydb";     string name = "name";     string pass = "pass";     connection connection;      try {         class.forname("com.mysql.jdbc.driver").newinstance();         system.out.println("connecting database...");         connection = drivermanager.getconnection(host, name,                 pass);         system.out.println("successful!!!");      } catch (sqlexception e) {         system.out.println("connecting database failed");         system.out.println(e.getmessage());         e.printstacktrace();     }     catch (classnotfoundexception e) {         e.printstacktrace();     } catch (instantiationexception e) {         e.printstacktrace();     } catch (illegalaccessexception e) {         e.printstacktrace();     } }

could please me this? thank you.

edit

the stack trace:

com.mysql.jdbc.exceptions.jdbc4.communicationsexception: communications link failure  last packet sent server 0 milliseconds ago. driver has not received packets server. @ sun.reflect.nativeconstructoraccessorimpl.newinstance0(native method) @ sun.reflect.nativeconstructoraccessorimpl.newinstance(nativeconstructoraccessorimpl.java:57) @ sun.reflect.delegatingconstructoraccessorimpl.newinstance(delegatingconstructoraccessorimpl.java:45) @ java.lang.reflect.constructor.newinstance(constructor.java:525) @ com.mysql.jdbc.util.handlenewinstance(util.java:411) @ com.mysql.jdbc.sqlerror.createcommunicationsexception(sqlerror.java:1121) @ com.mysql.jdbc.mysqlio.<init>(mysqlio.java:355) @ com.mysql.jdbc.connectionimpl.coreconnect(connectionimpl.java:2479) @ com.mysql.jdbc.connectionimpl.connectonetryonly(connectionimpl.java:2516) @ com.mysql.jdbc.connectionimpl.createnewio(connectionimpl.java:2301) @ com.mysql.jdbc.connectionimpl.<init>(connectionimpl.java:834) @ com.mysql.jdbc.jdbc4connection.<init>(jdbc4connection.java:47) @ sun.reflect.nativeconstructoraccessorimpl.newinstance0(native method) @     sun.reflect.nativeconstructoraccessorimpl.newinstance(nativeconstructoraccessorimpl.java:57) @ sun.reflect.delegatingconstructoraccessorimpl.newinstance(delegatingconstructoraccessorimpl.java:45) @ java.lang.reflect.constructor.newinstance(constructor.java:525) @ com.mysql.jdbc.util.handlenewinstance(util.java:411) @ com.mysql.jdbc.connectionimpl.getinstance(connectionimpl.java:416) @ com.mysql.jdbc.nonregisteringdriver.connect(nonregisteringdriver.java:317) @ java.sql.drivermanager.getconnection(drivermanager.java:579) @ java.sql.drivermanager.getconnection(drivermanager.java:221) @ databasehelper.main(databasehelper.java:17) caused by: java.net.connectexception: operation timed out @ java.net.plainsocketimpl.socketconnect(native method) @ java.net.abstractplainsocketimpl.doconnect(abstractplainsocketimpl.java:339) @ java.net.abstractplainsocketimpl.connecttoaddress(abstractplainsocketimpl.java:200) @ java.net.abstractplainsocketimpl.connect(abstractplainsocketimpl.java:182) @ java.net.sockssocketimpl.connect(sockssocketimpl.java:391) @ java.net.socket.connect(socket.java:579) @ java.net.socket.connect(socket.java:528) @ java.net.socket.<init>(socket.java:425) @ java.net.socket.<init>(socket.java:241) @ com.mysql.jdbc.standardsocketfactory.connect(standardsocketfactory.java:259) @ com.mysql.jdbc.mysqlio.<init>(mysqlio.java:305) ... 15 more

check database service , running on dedicated server.


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