java.sql.SQLException: Access denied for user ''@'localhost' (using password: NO)

So I'm getting the error java.sql.SQLException: Access denied for user ''@'localhost' (using password: NO) when I try to connect to MySQL Database from Java code. Everything I was able to find didn't solve the Problem at all and the code is very basic. I used it in projects before and found it like that in many tutorials. So first the relevant code:

//Inside class that manages SQLConnection
public SQLTransceiver(String url){
        this.connectionURL = url;
        this.reconnect();
}

public void reconnect(){
        try {
            Connection connection = DriverManager.getConnection(this.connectionURL); //Where the error occurs
            this.currentConnection = connection;
        } catch (SQLException e) {
            e.printStackTrace();
        }
}

//Inside main class I call this for testing purpose
String s = "jdbc:mysql://localhost:3306/tableName" +
                "?user=user" +
                "&password=thePassword" +
                "&serverTimezone=MET";

DataTransreciever transreciever = new SQLTransceiver(s);

NOTE: I can perfectly log into the DB in MySQL workbench and do everything there from creating/altering tables to inserting and all that stuff.

The whole Stacktrace looks like this:

java.sql.SQLException: Access denied for user ''@'localhost' (using password: NO)
	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.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:836)
	at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:456)
	at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:246)
	at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:197)
	at java.sql.DriverManager.getConnection(DriverManager.java:664)
	at java.sql.DriverManager.getConnection(DriverManager.java:208)
	at main.data.SQLTransceiver.reconnect(SQLTransceiver.java:31)
	at main.data.SQLTransceiver.<init>(SQLTransceiver.java:20)
	at main.ui.toDoPane.ToDoPane.<init>(ToDoPane.java:208)
	at main.ui.Window.start(Window.java:40)
	at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$161(LauncherImpl.java:863)
	at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$174(PlatformImpl.java:326)
	at com.sun.javafx.application.PlatformImpl.lambda$null$172(PlatformImpl.java:295)
	at java.security.AccessController.doPrivileged(Native Method)
	at com.sun.javafx.application.PlatformImpl.lambda$runLater$173(PlatformImpl.java:294)
	at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
	at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
	at com.sun.glass.ui.win.WinApplication.lambda$null$147(WinApplication.java:177)
	at java.lang.Thread.run(Thread.java:748)

So what did I do to fix this:
It made me wonder why it doesn't state which user was denied note it statets "denied for user ''@'localhost'. So I did put in wrong password and this error came:

java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: YES)
	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.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122)
	at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:836)
	at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:456)
	at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:246)
	at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:197)
	at java.sql.DriverManager.getConnection(DriverManager.java:664)
	at java.sql.DriverManager.getConnection(DriverManager.java:208)
	at main.data.SQLTransceiver.reconnect(SQLTransceiver.java:31)
	at main.data.SQLTransceiver.<init>(SQLTransceiver.java:26)
	at main.Main.main(Main.java:29)

So it looks like it at some point does check the user and password. It just gives the first error if user and password are correct.

So I did some lookup and got the solution that is stated for this question a few times (Although often it does state the "Using password: Yes" insted of "No"):

https://stackoverflow.com/questions/11922323/java-sql-sqlexception-access-denied-for-user-rootlocalhost-using-password

It states I should run following statement:

GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' IDENTIFIED BY '%password%' WITH GRANT OPTION;

The Problem is I can't run that. When I try to run it in MySQL Workbench I get the following error:

0	5	01:12:32	GRANT ALL PRIVILEGES ON *.* TO 'user'@'localhost' IDENTIFIED BY 'password' WITH GRANT OPTION	Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'IDENTIFIED BY 'password' WITH GRANT OPTION' at line 1	0.000 sec

Additionally I tried to remove MySQL completely and reinstall it. This didn't help.

Disclaimer:
Password and user was changed for privacy reasons.
In terms of errors it doesn't make a difference calling the DriverManager with connection String and Properties class I did try that to.
Sorry for more basic and maybe bad englisch.
I am using MySQL Server 8.0.20 Community with InnoDB Engine. The J/Connector and MySQL Notifier are for the same Version. I installed all (including the workbench) with the Windows Installer downloaded from: https://dev.mysql.com/downloads/mysql/
I am using Windows 10.

When I remove the "serverTimezone" parameter I get the following error:

java.sql.SQLException: The server time zone value 'Mitteleurop�ische Sommerzeit' 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:836)
	at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:456)
	at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:246)
	at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:197)
	at java.sql.DriverManager.getConnection(DriverManager.java:664)
	at java.sql.DriverManager.getConnection(DriverManager.java:208)
	at main.data.SQLTransceiver.reconnect(SQLTransceiver.java:31)
	at main.data.SQLTransceiver.<init>(SQLTransceiver.java:26)
	at main.Main.main(Main.java:28)

I don't know if that helps, but it's possible.

Thanks very much in advance

So what at least fixed the problem was to reinstall MySQL Server again.

The difference was this time I made sure to choose the 'new' password encryption ("caching_sha2_password") for every component (Server, Connector/J, Notifier and Workbench).

Altough I don't understand how this would cause an error like this or if that even was the error it fixed it.

Thanks for everyone who did there best to help

Please use the following connection url:

 String s = "jdbc:mysql://localhost:3306/databasename?user=user&password=password&useUnicode=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC";

I hope it's help you, thanks.