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Cant connect ot remote MySQL DataBase from JavaFX application

I have created an application, that communicates with a remote MySQL database, which is on my laptop. The app work fine, when I use my localhost to connect like this:
public class DbConncetion {
public Connection Connect(){
try {
Class.forName("com.mysql.jdbc.Driver");
Connection con= DriverManager.getConnection("jdbc:mysql://localhost:3306/cms?autoReconnect=true&useSSL=false","root","");
return con;
}
catch(Exception ex){
System.out.println(ex);
}
return null;
}
}
It works just great. But when I use my public IP addres instead of "localhost", the app throws:
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.
java.lang.NullPointerException
I look a lot in this forum, but I didn't find anything. I create user and give him all privileges in my XAMPP MySQL like that:
This is pic from there
I configure the router, but i'm not sure is it correct:
This is pic from there
Can anyone told me, where i go wrong ?
Thanks in advance :)
And this is the full stacktrace:
t
com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2088)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:806)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
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:425)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:410)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:328)
at java.sql.DriverManager.getConnection(DriverManager.java:664)
at java.sql.DriverManager.getConnection(DriverManager.java:247)
at DBconnection.DbConncetion.Connect(DbConncetion.java:24)
at javafxapplication1.Main1Controller.loadData(Main1Controller.java:208)
at javafxapplication1.Main1Controller.lambda$new$0(Main1Controller.java:232)
at com.sun.scenario.animation.shared.TimelineClipCore.visitKeyFrame(TimelineClipCore.java:239)
at com.sun.scenario.animation.shared.TimelineClipCore.playTo(TimelineClipCore.java:180)
at javafx.animation.Timeline.impl_playTo(Timeline.java:176)
at javafx.animation.AnimationAccessorImpl.playTo(AnimationAccessorImpl.java:39)
at com.sun.scenario.animation.shared.InfiniteClipEnvelope.timePulse(InfiniteClipEnvelope.java:110)
at javafx.animation.Animation.impl_timePulse(Animation.java:1102)
at javafx.animation.Animation$1.lambda$timePulse$25(Animation.java:186)
at java.security.AccessController.doPrivileged(Native Method)
at javafx.animation.Animation$1.timePulse(Animation.java:185)
at com.sun.scenario.animation.AbstractMasterTimer.timePulseImpl(AbstractMasterTimer.java:344)
at com.sun.scenario.animation.AbstractMasterTimer$MainLoop.run(AbstractMasterTimer.java:267)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:506)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:490)
at com.sun.javafx.tk.quantum.QuantumToolkit.lambda$runToolkit$404(QuantumToolkit.java:319)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
at java.lang.Thread.run(Thread.java:745)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
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:425)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:989)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:341)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2251)
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2104)
... 33 more
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.TwoStacksPlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:211)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:300)
... 35 more
Feb 18, 2017 2:23:03 PM DBconnection.DbConncetion Connect
SEVERE: null
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up.
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:425)
at com.mysql.jdbc.Util.getInstance(Util.java:408)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:918)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:897)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:886)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:860)
at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2163)

You must allow the application ip address in Mysql user configuration, in your pic you have masked the ip allowed, that ip must be the application server ip.
If you run your web application from the same local network of the DB Host you cannot connect to the public IP of your DB Host, the router cannot simply do that.
So for your local test you must use localhost.
When you will deploy the app you must use the public.
By the way, it is not a good practice to expose mysql db port to internet.

How Do I Connect To A Remote MySQL Database in Java? [duplicate]

This question already has answers here:
Connect Java to a MySQL database
(14 answers)
Closed 6 years ago.
I'm developing a Java application that (among other things) queries a remote database. I'm having trouble getting a connection to the database.
My code is:
private static String MYSQL_URL = "jdbc:mysql://db644874220.db.1and1.com";
private static String DB_NAME = "db644874220";
private static Connection CONNECTION;
static {
String dbUrl = MYSQL_URL + "/" + DB_NAME;
try {
Class.forName("com.mysql.jdbc.Driver");
CONNECTION = DriverManager.getConnection(dbUrl, MYSQL_USERNAME, MYSQL_PASSWORD);
} catch (SQLException | ClassNotFoundException e) {
e.printStackTrace();
}
}
The error I get is:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
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.SQLError.createCommunicationsException(SQLError.java:988)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:341)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2251)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2284)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2083)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:806)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
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.ConnectionImpl.getInstance(ConnectionImpl.java:410)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:328)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at com.joshuaevanslowell.IO.<clinit>(IO.java:41)
at com.joshuaevanslowell.Speculator.<init>(Speculator.java:46)
at com.joshuaevanslowell.Speculator.main(Speculator.java:32)
Caused by: java.net.ConnectException: Connection timed out: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:211)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:300)
... 17 more
I've seen some other questions dealing with this, but they generally assume that the database is on localhost, which mine isn't. I'm using 1&1 web hosting, and I can work with the database through my browser through phpMyAdmin. The information it gives about the server is
Server: db644874220.db.1and1.com via TCP/IP
Server type: MySQL
Server version: 5.5.50-0+deb7u2-log - (Debian)
Protocol version: 10
User: dbo644874220#10.72.2.9
Server charset: UTF-8 Unicode (utf8)
I feel like I'm doing something horribly wrong, and I just can't make head or tail of this.

If you have telnet client client installed assuming 3306 is the mysql port, please try
telnet ipaddress 3306.
I fear you may not have direct connectivity to mysql server. To enable this you may need to edit the configuration as answered in similar questions.
Also, please do close the DB connection or rather use a connection pool. Having too many open connections(above the configured limit) may cause similar issues.

my guess is that the db644874220.db.1and1.com host is not known from the location where you run your Java code
try to do ping db644874220.db.1and1.com from the machine where you run the Java code or telnet db644874220.db.1and1.com 3306. If neither return a result it means that you don't have a way to access that machine via its name.
Either use the IP instead if you know it or add a line in your hosts file
[IP address] db644874220.db.1and1.com

MySql with JAVA error. The last packet sent successfully to the server was 0 milliseconds ago [duplicate]

This question already has answers here:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
(51 answers)
Closed 4 years ago.
I have read about this exception a lot, but I can't solve my.
Mysql server is working.
I can connect to it from NetBeans, but I can't connect to it from java code.
Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
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:525)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1116)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:344)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2332)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2369)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2153)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:792)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
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:525)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:381)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:305)
at java.sql.DriverManager.getConnection(DriverManager.java:579)
at java.sql.DriverManager.getConnection(DriverManager.java:243)
at javaapplication3.JavaApplication3.main(JavaApplication3.java:32)
Caused by: java.net.SocketException: Permission denied: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:69)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:157)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:391)
at java.net.Socket.connect(Socket.java:579)
at java.net.Socket.connect(Socket.java:528)
at java.net.Socket.<init>(Socket.java:425)
at java.net.Socket.<init>(Socket.java:241)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:257)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:294)
... 15 more
Java Result: 1
I catch this exception with any ways to connect to Mysql from java code, but from MysqlWorkBench and from NetBeans is OK.
I have no Firewall. I tried 127.0.0.1, result is the same.

Search the file my.cnf and comment the line
skip-networking
to
#skip-networking
Restart mysql

Try to specify the port in
conn = DriverManager.getConnection("jdbc:mysql://localhost/mysql?"
+ "user=root&password=onelife");
I think you should have something like this:
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql?"
+ "user=root&password=onelife");
Also, the port number in my example (3306) is the default port, but you may change it while installing MySQL.
I think that a better way to specify password and user is to separate them from the URL like this:
connection = DriverManager.getConnection(url, login, password);

THis issue has been fixed with new mysql connectors,
please use http://mvnrepository.com/artifact/mysql/mysql-connector-java/5.1.38
I used to get this error after updating the connector jar, issue resolved.

The problem is mostly due to a MySQL service that is not running, so make sure it is. If it isn't, run this CMD with administrator privilege in order to start it:
sc start [Your MySQL Service name]

Try the following suggestions:
Your machine may have a static IP; map this IP to the hosts file as localhost.
Try to log in from your computer or within the network via mysql command; if login is successful, it means that MySQL runs fine.

There are two things
Disable firewall if any or add exception or check if u have correct driver file. Disable any antivirus if any
and also make sure your driver type is mysql.jdbc.driver.

It seems that your Java code is using IPv6 instead of IPv4. Please try to use 127.0.0.1 instead of localhost. Ex.: Your connection string should be
jdbc:mysql://127.0.0.1:3306/expeditor?zeroDateTimeBehavior=convertToNull&user=root&password=onelife
P.S.: Please update the URL connection string.

Increasing client packet size for a Java connection to a mySQL DB

I'm trying to connect to an external mySQL DB through a Java program. When I attempt to connect, I obtain the following exception:
Exception in thread "main" com.mysql.jdbc.PacketTooBigException: Packet for query is too large (4739923 > 1048576). You can change this value on the server by setting the max_allowed_packet' variable.
at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:605)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1078)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2397)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2430)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2215)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:813)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
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:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:399)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:334)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at Main.main(Main.java:48)
This is only for this external server. I was able to connect to a local server I set up without this issue at all.
I did some research on this and it talked about increasing my client max_allowed_packet size through a /etc/my.cnf file. I attempted to do this without any success. Would somebody be able to walk me through this as I can't even find the .cnf file. Is this even the right approach for a Java based connection?
Thanks in advance.

On the server, you must change your mysql configuration file. You will need to find it based on your operation system. See https://dev.mysql.com/doc/refman/5.6/en/option-files.html
You should not need to do anything on the client side to set this. Just send a large amount of data.

glassfish and restfull webservice exception

I'm quite new to java webservices. I deployed a restfull web service on glassfish. Web service works well for about 10 or 20 hours and then the system doesn't respond. Below is the exception thrown everytime the service is called (After the system breaks). Please tell me why this exception is thrown.
Thanks
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after statement closed.
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:525)
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:1013)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:987)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:982)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:927)
at com.mysql.jdbc.StatementImpl.checkClosed(StatementImpl.java:458)
at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1418)
at datamodel.Question_Data_Factory.getFilteredQData(Question_Data_Factory.java:44)

Reason was jdbc driver connection closes automatically when it is idle for a long time. setting conncetTimeout to 0 resolved the problem