JPA composite primary key [duplicate]
Recently I created ManyToMany relation using Composite Primary key and annotation as bi directional @OneToMany. This code works flawless. Maybe it will help:
Mapping ManyToMany with composite Primary key and Annotation:
Since you are using @IdClass, the PricePK class need not be marked with the @Embeddable annotation. An example is given in http://www.java2s.com/Code/Java/JPA/SetIdClassforCompoundKey.htm
I tried your code removing the @Embeddable on PricePK class, and the price table generated in MYSQL database with not null fields.
Following is how you could use @EmbeddedId to achieve the required result:(getters and setters omitted)
@Entity@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)public class Price { @EmbeddedId PricePK pricePk;}@Embeddablepublic class PricePK implements Serializable { @ManyToOne(optional = false) private Product product; @ManyToOne(optional = false) private Currency currency;}