Java Persistence API

Entity Relationships

One-to-One

One-to-One Example

One-to-Many

One-to-Many Example

Many-to-Many

Many-to-Many Example

  @Entity
  public class Employee {
    ...
    @ManyToMany(mappedBy="employees") // Manager is the "owner"
    public Set<Manager> getManagers() {
        return managers;
    }
    ...
  }

  @Entity
  public class Manager {
    ...
    @ManyToMany
    public Set<Employee> getEmployees() {
        return employees;
    }
    ...
  }