Spring Boot : Error creating bean with name 'jpaMappingContext': java.lang.NullPointerException

Question

My combination of is Spring Boot + Spring Data Jpa + Multiple Databases. I am getting following NullPointer exception when starting the application. Feels like SPring Data with

Answer 1

I faced the mentioned issue with mapping in OnetoOne relationship..

My app had the following OneToOne relationship.

A ||---|| B

B ||---|| C

Since its OnetoOne, I kept entity B primary key same as entity A, using @MapsId as mentioned here 

https://vladmihalcea.com/the-best-way-to-map-a-onetoone-relationship-with-jpa-and-hibernate/

Similarly I kept entity C primary key same as entity B.

I fixed this by changing the relationship like this

A ||---|| B

A ||---|| C