由于时区不正确，无法连接到 MySQL

Question

我已经制作了一个 java 应用程序，我想在打开窗口时尝试连接到 sql 数据库。我添加了 my-sql-java-8.0.14.jar 连接器，但是当我运行应用程序时，我收到一条错误消息。 我已尝试多次重新连接、重新构建数据库并连接新数据库，但我仍然收到以下错误消息。

提前感谢您的帮助

 "Exception in thread "AWT-EventQueue-0" java.lang.IllegalStateException: Cannot connect to the dbat testDBPack.MainWindow$1.windowOpened(MainWindow.java:47)
    at java.awt.Window.processWindowEvent(Unknown Source)
    at javax.swing.JFrame.processWindowEvent(Unknown Source)
    at java.awt.Window.processEvent(Unknown Source)
    at java.awt.Component.dispatchEventImpl(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Window.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$500(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)
Caused by: java.sql.SQLException: The server time zone value '????????? ??? GTB' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73)
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:76)
    at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:835)
    at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:455)
    at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:240)
    at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:199)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at testDBPack.MainWindow$1.windowOpened(MainWindow.java:45)
    ... 25 more
Caused by: com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server time zone value '????????? ??? GTB' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.
    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.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61)
    at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:85)
    at com.mysql.cj.util.TimeUtil.getCanonicalTimezone(TimeUtil.java:132)
    at com.mysql.cj.protocol.a.NativeProtocol.configureTimezone(NativeProtocol.java:2241)
    at com.mysql.cj.protocol.a.NativeProtocol.initServerSession(NativeProtocol.java:2265)
    at com.mysql.cj.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:1319)
    at com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:966)
    at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:825)
    ... 31 more
"

我已经检查了我的凭据，我正在运行 sql，但我无法解决问题。

import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Connection;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;


import javax.swing.JLabel;
import javax.swing.JSeparator;
import java.awt.Color;
import java.awt.Font;
import javax.swing.JButton;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

@SuppressWarnings("serial")
public class MainWindow extends JFrame {

    JPanel contentPane;
    static Connection conn;

    public MainWindow() {
        setResizable(false);
        setTitle("Coding Factory");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);


        setBounds(100, 100, 433, 293);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        setContentPane(contentPane);
        contentPane.setLayout(null);
        addWindowListener(new WindowAdapter() {
            @Override
            public void windowOpened(WindowEvent e) {

                String url = "jdbc:mysql://localhost:3306/teachers";
                String username = "panos123";
                String password = "panagiotis";

                try {
                    conn = DriverManager.getConnection(url,username,password);
                }catch (SQLException ex) {
                    throw new IllegalStateException("Cannot connect to the db",ex);
                }
            }
        });
        JLabel lblNewLabel_1 = new JLabel("Quality Assistance");
        lblNewLabel_1.setFont(new Font("Tahoma", Font.PLAIN, 30));
        lblNewLabel_1.setBounds(71, 32, 295, 37);
        contentPane.add(lblNewLabel_1);

        JButton TeachersButton = new JButton(" ");
        TeachersButton.setBounds(10, 144, 46, 34);
        contentPane.add(TeachersButton);

我还有另一个主课：

package testDBPack;

import java.awt.EventQueue;

public class TeachersApp {
    static MainWindow mainFrame;

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    mainFrame = new MainWindow();
                    mainFrame.setVisible(true);
                    mainFrame.setLocationRelativeTo(null);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }
}

Answer 1

时区未配置。尝试使用以下网址：

jdbc:mysql://localhost/teachers?useUnicode=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC