embedding - JPA @EmbeddedId: How to update part of a composite primary key? -

i have many-to-many relationship link table has additional property. hence link table represented entity class , called composition. primary key of composition @embeddable linking according entities, eg. 2 @manytoone references.

it can happen user makes error when selecting either of 2 references , hence composite primary key must updated. due how jpa (hibernate) works of course create new row (insert) instead of update , old composition still exist. end result being new row added instead of 1 being updated.

option 1:

the old composition deleted before new 1 inserted require according method handling requires both old , new version. plus since updated version new entity optimistic locking not work , hence last update win.

option 2:

native query. query increments version column , includes version in clause. throw optimisticlockexception if update count 0 (concurrent modification or deletion)

what better choice? "common approach" issue?

why not change primary key of composition uid auto-generated? users change 2 references entities being joined without having delete/re-create composition entity. optimistic locking maintained.

edit: example:

@entity @table(name = "composition") public class composition {      @id     @column(name = "id")     private long id;   // auto-generate using preferred method      @manytoone(fetch = fetchtype.lazy, optional = false)     @joincolumn( .... appropriate .... )     private firstentity firstentity;      @manytoone(fetch = fetchtype.lazy, optional = false)     @joincolumn( .... appropriate .... )     private secondentity secondentity;  ....