hibernate - 地图上主键的注释问题

Question

以下代码使用字段“Propriedade”和“doc_id”生成一个表，其中存在 PK 约束。

我想知道我可以用来指定 PK 的最合适的注释是什么？

 public class Documento {
        @Id
        @GeneratedValue(strategy=GenerationType.SEQUENCE)
        private long id;
        private String numero;
        private TipoDeMidia midia;
        private String nomeDoArquivo;
        @ElementCollection
        @MapKeyColumn(name="propriedade")
    @Column(name="valor")
        @CollectionTable(name="DOCINFO",joinColumns=@JoinColumn(name="doc_id"))
        private Map<String,String> informacoesDoDocumento= new HashMap<String, String>();

这是生成的SQL

CREATE TABLE docinfo
(
  doc_id bigint NOT NULL,
  valor character varying(255),
  propriedade character varying(255) NOT NULL,
  CONSTRAINT docinfo_pkey PRIMARY KEY (doc_id, propriedade),
  CONSTRAINT fk97c919c6e3b42d44 FOREIGN KEY (doc_id)
      REFERENCES documento (id) MATCH SIMPLE
      ON UPDATE NO ACTION ON DELETE NO ACTION
)