step 1

import the library_db_backup.sql into mysql database.

step 2

change the file hibernate.cfg.xml(src/main/resources)
In the line name="connection.username" change the username as your mysql username
In the line name="connection.password" change the password as your mysql password

step 3

open project structure/Artifacts delete all the artifacts remained in the Artifacts and use "+" to add a "Web Application: Exploded From Models" select LibrarySystem.

step 4

Open "Run/Debug Configurations", select "tomcat", select "Deployment" delete remained artifact and add a new artifact use "+" then choose apply. Please choose a not occupied port in run configuration

step 5

Use run to start the project.