@Entity
@Table( name = "T_TABLE_L")
public class ClasseL implements Serializable
{
  @Id
  @GeneratedValue( strategy = GenerationType.IDENTITY )
  @Column( name = "L_ID" )
  private Long id;
  
  @Column( name = "L_REMARQUE" )
  private String remarque;
  
  @OneToMany( mappedBy = "classeL", cascade =  CascadeType.PERSIST )
  private List< ClasseLM > listeM;
...