java - Bidirectional mapping in hibernate -

i have 2 tables, quotation , quotation_item. there 1 many relationship them. requirement when quotation.setquotationitem(set), old quotationitem mapped quotation should removed , quotationitems in set should mapped against quotation.

/*** quotation pojo ****/

    public class quotation {     int quotationid;     string code;     string clientname;     set<quotationitem> quotationitem=new hashset<quotationitem>();     //getter , setter     } 

/*** quotationitem pojo ****/

    public class quotationitem extends quotation{     int id;     quotation quotation;     string itemname;     int rate;     int qty;     //getter , setter     } 

/** quotation.hbm ********/

    <hibernate-mapping>     <class name="com.paramatrix.pojo.quotation" table="quotation" >     <id name="quotationid" type="int" column="quotation_id">     <generator class="native" />     </id>     <property name="code" column="code" type="string" />     <property name="clientname" column="client_name" type="string" />     <set name="quotationitem" table="quotation_item" cascade="save-update" inverse="true">     <key>     <column name="quotation_id" not-null="true" />     </key>     <one-to-many class="com.paramatrix.pojo.quotationitem" />     </set>     </class>     </hibernate-mapping> 

/** quotationitem.hbm ******/

    <class name="com.paramatrix.pojo.quotationitem" table="quotation_item" dynamic-insert="true">     <id name="id" type="int" column="id">     <generator class="native" />     </id>     <many-to-one name="quotation" class="com.paramatrix.pojo.quotation" >     <column name="quotation_id" not-null="true" />     </many-to-one>     <property name="itemname" column="item_name" type="string" />     <property name="rate" column="rate" type="int" />     <property name="qty" column="qty" type="int" />     </class> 

my tables structure quotation

quotation_id code client_name

my table structure quotation_item

id quotation_id item_name rate qty

try modify set rather replace it. i.e.:

    quotation.getquotationitem().clear();     quotation.getquotationitem().addall(newset); 

this due hibernate weirdness.

aside, small point naming. quotation.quotationitem should named quotationitems contains more 1 quotationitem.