LazyInitializationException: could not initialize proxy

cat4hire · **Joined:** Tue Nov 27, 2007 6:11 am **Posts:** 12

Hi,
I'm trying to write an application based on hibernate 3, I'm using the cglib2.1.3 and when I run my application I got the following exception:

Code:

Exception in thread "main" org.hibernate.LazyInitializationException: could not initialize proxy - no Session
   at org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:57)
   at org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:111)
   at org.hibernate.proxy.pojo.cglib.CGLIBLazyInitializer.invoke(CGLIBLazyInitializer.java:150)
   at g2.database.mapping.Person$$EnhancerByCGLIB$$c482508f.getName(<generated>)
   at main.Main.main(Main.java:26)

The application is very simple: I've got a person table and a role table, and the following are the mappings:

Code:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
   "-//Hibernate/Hibernate Mapping DTD//EN"
   "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd" >

<hibernate-mapping package="g2.database.mapping">
   <class
      name="Person"
      table="person"
   >
      <meta attribute="sync-DAO">true</meta>
      <id
         name="Id"
         type="string"
         column="personid"
      >
         <generator class="sequence"/>
      </id>

      <property
         name="Personpk"
         column="personpk"
         type="integer"
         not-null="true"
         length="10"
      />
      <property
         name="Name"
         column="name"
         type="string"
         not-null="false"
         length="20"
      />
      <property
         name="Surname"
         column="surname"
         type="string"
         not-null="false"
         length="20"
      />
      <property
         name="Borndate"
         column="borndate"
         type="date"
         not-null="false"
         length="13"
      />
      <property
         name="Phone"
         column="phone"
         type="string"
         not-null="false"
         length="50"
      />
      <property
         name="Mobilephone"
         column="mobilephone"
         type="string"
         not-null="false"
         length="50"
      />
      <property
         name="Fax"
         column="fax"
         type="string"
         not-null="false"
         length="50"
      />
      <property
         name="Email"
         column="email"
         type="string"
         not-null="false"
         length="50"
      />
      <property
         name="Web"
         column="web"
         type="string"
         not-null="false"
         length="100"
      />
      <property
         name="RecordDate"
         column="record_date"
         type="date"
         not-null="false"
         length="13"
      />
   


    <set name="roles" table="j_person_role" >
        <key column="personpk"/>
        <many-to-many column="rolepk"
            unique="true"
            class="Role"  />
    </set>

      

   </class>   
</hibernate-mapping>




<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
   "-//Hibernate/Hibernate Mapping DTD//EN"
   "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd" >

<hibernate-mapping package="g2.database.mapping">
   <class
      name="Role"
      table="role"
   >
      <meta attribute="sync-DAO">true</meta>
      <id
         name="Id"
         type="integer"
         column="rolepk"
      >
         <generator class="sequence"/>
      </id>

      <property
         name="Roleid"
         column="roleid"
         type="string"
         not-null="true"
         length="50"
      />
      <property
         name="Rolerevision"
         column="rolerevision"
         type="java.lang.Long"
         not-null="true"
         length="10"
      />
      <property
         name="Description"
         column="description"
         type="string"
         not-null="false"
         length="100"
      />
      <property
         name="Revisioncomment"
         column="revisioncomment"
         type="string"
         not-null="false"
         length="100"
      />
      <property
         name="Creationdate"
         column="creationdate"
         type="date"
         not-null="false"
         length="13"
      />
      <property
         name="Revisiondate"
         column="revisiondate"
         type="date"
         not-null="false"
         length="13"
      />
   



   </class>   
</hibernate-mapping>

If I set all the classes and collection with lazy="false" the application works. Is there a way to use the lazy loading? Please note that I'm not using any container. Moreover, is it suggested to use lazy loading for standard java applications?

Thanks,
Luca

farzad · **Posted:** Mon Dec 17, 2007 12:28 am

what is the code that causes this problem?

Farzad-

msj4u · **Joined:** Wed Apr 25, 2007 11:44 pm **Posts:** 59

dude

you have closed the connection and you are trying to access the proxy object which is no fully initialized; because it needs an open connection for initilization.

check your code buddy

cat4hire · **Joined:** Tue Nov 27, 2007 6:11 am **Posts:** 12

msj4u wrote:

dude

you have closed the connection and you are trying to access the proxy object which is no fully initialized; because it needs an open connection for initilization.

check your code buddy

How can you say that I've closed the connection? Can you be more specific?
Thanks.

ramnath · **Posted:** Mon Dec 17, 2007 7:34 am

Hi,

Above posters are saying u that u have closed the connection before initializing the child...

for eg.
Session session = getSession(); //May be from ur super class or utility class
Person person = (Person) session.load()// normal way..
session.close();

so after this line if you try to invoke,
parent.getRoles(), you will have lazyInitializationException...To avoid this can specify it in the mapping file. or before the session.close() line insert the below line.
Hibernate.intialize(parent.getRoles());

Hope this helps:-)