I have a spring boot application with two classes – Load and Location. The relationship between location and load is oneToMany.

In my application.properties file I have set spring.jpa.hibernate.ddl-auto=update.

When I initially tried to start the application, hibernate could not establish the foreign key relationship between the tables due to a syntax error. I added it manually and now I get the error:

2024-04-25T09:58:13.743+02:00 ERROR 12760 --- [putaway] [           main] com.zaxxer.hikari.HikariConfig           : Failed to load driver class com.mysql.cj.jdbc.Driver from HikariConfig class classloader jdk.internal.loader.ClassLoaders$AppClassLoader@1d44bcfa
2024-04-25T09:58:13.744+02:00  WARN 12760 --- [putaway] [           main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'dataSourceScriptDatabaseInitializer' defined in class path resource 
[org/springframework/boot/autoconfigure/sql/init/DataSourceInitializationConfiguration.class]: Unsatisfied dependency expressed through method 'dataSourceScriptDatabaseInitializer' parameter 0: Error creating bean with name 'dataSource' defined in class path resource 
[org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class]: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception with message: 
Failed to load driver class com.mysql.cj.jdbc.Driver in either of HikariConfig class loader or Thread context classloader

These are my Entity classes:
Location.java

@Entity
@Data
public class Location implements Comparable<Location> {
    @Id
    private String id;
    private LocationCapacity capacity;
    @OneToOne
    @JoinColumn(name = "merchandise_id")
    private Merchandise merchandise;
    @OneToMany
    private List<Load> loads;

    @Override
    public int compareTo(Location o) {
        return 0;
    }

    public Integer getCount() {
        int count = 0;
        for (Load l : loads) {
            count += l.getNumberOfCases();
        }
        return count;
    }

    public static class Comparators {
        public static Comparator<Location> caseCount = Comparator.comparing(Location::getCount);

    }
}

Load.java

@Data
@Entity
public class Load {
    @Id
    private Integer loadNumber;
    @OneToOne
    @JoinColumn(name = "merchandise_crc")
    private Merchandise merchandise;
    private Integer numberOfCases;
}

I also have a Merchandise entity which is referenced in both the Location and Load classes:

@Entity
@Data
public class Merchandise {
    @Id
    private String crc;
    private String name;
    private MerchandiseSize size;
    @OneToMany(mappedBy = "id")
    private List<Location> locations;
}

This application has run and returned responses to Postman prior to adding the Load entity.