无法将 java 连接到远程 Mysql 数据库服务器

Question

我在这个网站上用数据库创建了帐户：byethost

并且我正在尝试使用在我尝试连接到我的计算机上的本地数据库时有效的代码来连接它。

Main.dataSource.setServerName("sql201.byethost33.com");
    Main.dataSource.setDatabaseName("b33_16132071_pizza_service");
    Main.dataSource.setUser("myuser");
    Main.dataSource.setPassword("mypassword");

    try( Connection connection = Main.dataSource.getConnection() ){
        labStatus.setText("Connection to " + databaseName + " succeed");
        labStatus.setStyle("-fx-text-fill: green");

        showLoginButtons();
    }catch(Exception ex){
        labStatus.setText("Connection to " + databaseName + " failed");
        labStatus.setStyle("-fx-text-fill: red");

        ExceptionDialog exceptionDialog = new ExceptionDialog("Couldn't reach the connection", ex);
        exceptionDialog.show();
    }

我收到此错误：

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.GeneratedConstructorAccessor9.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:389)
    at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1038)
    at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:338)
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2237)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2270)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2069)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:794)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:44)
    at sun.reflect.GeneratedConstructorAccessor6.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:389)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:399)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:325)
    at com.mysql.jdbc.jdbc2.optional.MysqlDataSource.getConnection(MysqlDataSource.java:422)
    at com.mysql.jdbc.jdbc2.optional.MysqlDataSource.getConnection(MysqlDataSource.java:134)
    at com.mysql.jdbc.jdbc2.optional.MysqlDataSource.getConnection(MysqlDataSource.java:105)
    at controller.MainWindowController.menuItemTestConnectionAction(MainWindowController.java:60)
    at sun.reflect.GeneratedMethodAccessor11.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at sun.reflect.misc.Trampoline.invoke(Unknown Source)
    at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at sun.reflect.misc.MethodUtil.invoke(Unknown Source)
    at javafx.fxml.FXMLLoader$MethodHandler.invoke(Unknown Source)
    at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(Unknown Source)
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(Unknown Source)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
    at com.sun.javafx.event.EventUtil.fireEventImpl(Unknown Source)
    at com.sun.javafx.event.EventUtil.fireEvent(Unknown Source)
    at javafx.event.Event.fireEvent(Unknown Source)
    at javafx.scene.control.MenuItem.fire(Unknown Source)
    at com.sun.javafx.scene.control.skin.ContextMenuContent$MenuItemContainer.doSelect(Unknown Source)
    at com.sun.javafx.scene.control.skin.ContextMenuContent$MenuItemContainer.lambda$createChildren1(Unknown Source)
    at com.sun.javafx.scene.control.skin.ContextMenuContent$MenuItemContainer$$Lambda8/1546169402.handle(Unknown Source)
    at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(Unknown Source)
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(Unknown Source)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
    at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(Unknown Source)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
    at com.sun.javafx.event.EventUtil.fireEventImpl(Unknown Source)
    at com.sun.javafx.event.EventUtil.fireEvent(Unknown Source)
    at javafx.event.Event.fireEvent(Unknown Source)
    at javafx.scene.Scene$MouseHandler.process(Unknown Source)
    at javafx.scene.Scene$MouseHandler.access00(Unknown Source)
    at javafx.scene.Scene.impl_processMouseEvent(Unknown Source)
    at javafx.scene.Scene$ScenePeerListener.mouseEvent(Unknown Source)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(Unknown Source)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent0(Unknown Source)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$$Lambda6/1708139015.get(Unknown Source)
    at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(Unknown Source)
    at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(Unknown Source)
    at com.sun.glass.ui.View.handleMouseEvent(Unknown Source)
    at com.sun.glass.ui.View.notifyMouse(Unknown Source)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.lambda$null5(Unknown Source)
    at com.sun.glass.ui.win.WinApplication$$Lambda/2117255219.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
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:213)
    at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:297)
    ... 70 more

这是我第二次尝试连接到远程数据库。我第一次使用这个网站 db4free

我只是使用了这样的数据：

server: www.db4free.net
database: mydatabase
username: username
password: mypassword

我可以使用上面发布的相同 java 代码成功连接...

我看到这两个站点上的内容不同，所以我不知道我做错了什么。

也许我应该为 dataSource 对象设置一些端口或其他东西？也许这会解释一些事情：这是我在 db4free 的 phpMyAdmin 中看到的，我可以毫无问题地连接到数据库：

Database server

Server: 127.0.0.1 via TCP/IP
Server type: MySQL
Server version: 5.6.24 - MySQL Community Server (GPL)
Protocol version: 10
User: pizzaadm4@localhost
Server charset: UTF-8 Unicode (utf8)

这就是我在 phpMyAdmin ot byethost 中看到的我无法连接的地方

Database server

Server: sql201.byethost33.com via TCP/IP
Software: Percona Server
Software version: 5.6.22-71.0 - Percona Server (GPL), Release 71.0, Revision 726
Protocol version: 10
User: b33_1613071@192.168.0.6
Server charset: UTF-8 Unicode (utf8)

Answer 1

我想我在站点的控制面板中找到了答案...

无法将 java 连接到远程 Mysql 数据库服务器

Cannot connect java to remote Mysql database server

java

mysql

database-connection