1 Reply Latest reply on May 13, 2006 11:20 PM by Andy Leung

    How do map one-to-many properly?

    Andy Leung Newbie

      I have a scenario, which is very easy: Gender 1 --- * Singer

      So in Singer class, I have a Gender object where in Gender class, I have list of Singer objects. Here are the source codes:

      public class Gender implements Serializable {
       private long id;
       private String type;
       private String description;
       private List singer;
       public Gender() {
       super();
       // TODO Auto-generated constructor stub
       }
       public String getDescription() {
       return description;
       }
       public void setDescription(String description) {
       this.description = description;
       }
       public long getId() {
       return id;
       }
       public void setId(long id) {
       this.id = id;
       }
       public String getType() {
       return type;
       }
       public void setType(String type) {
       this.type = type;
       }
       public List getSinger() {
       return singer;
       }
       public void setSinger(List singer) {
       this.singer = singer;
       }
      }
      


      public class Singer implements Serializable {
       private long id;
       private String firstname;
       private String lastname;
       private Gender gender;
      
       public Singer() {
       super();
       // TODO Auto-generated constructor stub
       }
      
       public String getFirstname() {
       return firstname;
       }
       public void setFirstname(String firstname) {
       this.firstname = firstname;
       }
       public Gender getGender() {
       return gender;
       }
       public void setGender(Gender gender) {
       this.gender = gender;
       }
       public long getId() {
       return id;
       }
       public void setId(long id) {
       this.id = id;
       }
       public String getLastname() {
       return lastname;
       }
       public void setLastname(String lastname) {
       this.lastname = lastname;
       }
      }
      


      These are their mapping files:

      <hibernate-mapping>
       <class name="net.andyleung.multimedia.mp3.entity.Gender" table="gender">
       <id name="id" column="id">
       <generator class="native"/>
       </id>
       <property name="description" column="description" />
       <property name="type" column="type" />
      
       <list name="singer">
       <key column="id" not-null="true"/>
       <list-index column="gender"/>
       <one-to-many class="Singer"/>
       </list>
       </class>
      </hibernate-mapping>
      


      <hibernate-mapping>
       <class name="net.andyleung.multimedia.mp3.entity.Singer" table="singer">
       <id name="id" column="id">
       <generator class="native"/>
       </id>
       <property name="firstname"/>
       <property name="lastname"/>
       <many-to-one name="gender" class="Gender" column="gender" not-null="true" update="false" insert="false"/>
       <!--
       <many-to-one name="country" class="Country" column="country" not-null="true" update="false" insert="false"/>
       <list name="album">
       <key column="singer" not-null="true"/>
       <list-index column="singer"/>
       <one-to-many class="Album"/>
       </list>-->
       </class>
      
      </hibernate-mapping>
      


      But somehow it says my Singer is mapping incorrectly. Any clue?

      Thanks.