If a class that will be used as an embedded id has a column that is defined by an @Formula attribute, hibernate throws a NPE. This is because the below method in org.hibernate.cfg.Ejb3Column doesn't check if the mappingColumn is null (which it is when the column is defined by a formula) before dereferencing it.

public void forceNotNull() {
mappingColumn.setNullable( false );
}

To fix, change the method to:

public void forceNotNull() {
if (mappingColumn != null) {
mappingColumn.setNullable( false );
}
}