The reason is that I imported the webapps project “woniusales.war” in tomcat, started tomcat by double-clicking startup.bat, and reported an error in the black box. Open localhost:8080/woniusales and find that the project was not successfully configured.
[Severe] com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException
The reason for the error is: the mysql version on the computer is high, and the mysql-java driver version in the project is too low, and the two do not match.
Solution steps:
1. mysql>select version(); Check the mqsql version, my version is 8.0.19.
2. Go to the official website to download the corresponding version of the mysql-java driver, MySQL :: Download MySQL Connector/J (Archived Versions)
Then unzip the file, in the webappswoniusalesWEB-INFlib folder, use mysql-connector-java-8.0.19.jar Replace the original mysql-connector-java-5.xxx.jar
3. Find the db.properties file in your project in the webapps directory and open it with Notepad.
db_url=jdbc:mysql://localhost:3306/xxxxxx add ** & amp;serverTimezone=UTC** at the end
db_username and db_password are the same as your local database username/password
Change db_driver to com.mysql.cj.jdbc.Driver (mysql 5.xxx driver class here is com.mysql.jdbc.Driver)
4. Double-click startup.bat again, there is no error, open localhost:8080/woniusales, the project runs successfully!
Last
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