java - Hibernate one-to-one XML mapping -

i found following links:

• hibernate 1 one mapping problem
• hibernate one-to-one mapping reference column (xml mapping)
• hibernate one-to-one (on foreign key) vs one-to-one (on primary key)

but nothing seems work.

i have 2 entities:

class user {     integer userid;     profile userprofile; }  class profile {     integer profileid;     user user; } 

with xml mapping:

<?xml version="1.0"?> <!doctype hibernate-mapping public "-//hibernate/hibernate mapping dtd 3.0//en" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <hibernate-mapping>     <class name="model.user" table="user" catalog="proj1" dynamic-update="true">         <id name="userid" type="java.lang.integer">             <column name="userid" />             <generator class="identity" />         </id>         <one-to-one name="userprofile" class="model.profile">         </one-to-one>     </class> </hibernate-mapping>  <?xml version="1.0"?> <!doctype hibernate-mapping public "-//hibernate/hibernate mapping dtd 3.0//en" "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> <!-- generated jun 12, 2013 7:51:22 pm hibernate tools 3.4.0.cr1 --> <hibernate-mapping>     <class name="model.profile" table="profile" catalog="proj1" dynamic-update="true">         <id name="profileid" type="java.lang.integer">             <column name="profileid" />             <generator class="identity" />         </id>         <many-to-one name="user" class="model.users" unique="true">             <column name="userid" />         </many-to-one>     </class> </hibernate-mapping> 

the thing here is, user must have 1 profile profile doesn't have 1 user profile may have null user.

now problem every time fetch user associated profile, profile retrieved profile profileid same userid, if user has userid 4 profile retrieved profile profileid 4 though supposed retrieve profile userid 4 not profileid 4.

update: add dao code

public user findbyid( int id ) {     log.debug("getting user instance id: " + id);     try {         criteria usercriteria = this.sessionfactory.getcurrentsession().createcriteria(user.class);         usercriteria.add(restrictions.ideq(id));          usercriteria.setfetchmode("userprofile", fetchmode.join);          usercriteria.setresulttransformer(criteriaspecification.distinct_root_entity);         users instance = (users) usercriteria.uniqueresult();          if(instance == null)             log.debug("get successful, no instance found");         else             log.debug("get successful, instance found");         return instance;     }     catch(runtimeexception re) {         log.error("get failed", re);         throw re;     } } 

finally found solution. had set userprofile manually every time need fetch associated userprofile of user temporary workaround. found link: http://docs.jboss.org/hibernate/orm/3.3/reference/en/html/associations.html#assoc-bidirectional-121

so have add unique="true" not-null="false" many-to-one of user in profile xml , add property-ref="user" one-to-one userprofile in user. think key here property-ref="user"