Hibernate program exception: Java. Lang. unsupportedoperationexception: the user must supply a JDBC Co

Java. Lang. unsupportedoperationexception: the user must supply a JDBC connection
When such an exception occurs, it must be very depressing. I searched the internet and said that I was confused for a few days. In the end, I did not provide a solution, because I felt that I was writing quite right,
I did not even find any errors. I did. I did not find any errors after searching for a long time. I checked the program template one by one with me,
It turns out that there is an extra space in the configuration of the database path in my hibernate. cfg. XML, which is not obvious. Well, just remove the space!

<Property name = "hibernate. Connection. url"> JDBC: mysql: // localhost/hibernate_first </property>
No space in the red background!