外鍵關聯復合主鍵

@ManyToOne(fetch = FetchType.LAZY, optional = true)
    @JoinColumns(value={
            @JoinColumn(name ="ROADID", referencedColumnName ="ID",insertable=false, updatable=false),
            @JoinColumn(name="CITYID", referencedColumnName = "CITYID",insertable=false, updatable=false)
    })