RE: Lazy Loading not working

[Christopher . Mathrusse]

I found the problem. I was trying to be clever and support a bi-directional relationship.

 

Message -- 1* --> MessageMetaData

MessageMetaData -- *1 --> Message

 

 

I had my SQLMap defined as follows for the MetaData column:

result column="Message_id" property="metaData" select="MessageMetaData.findByMessageId"

I already know that iBatis cannot support a circular relationship so the MessageMetaData SQLMap did not try to load the Message associated to the MetaData. Instead I tried a little trick inside the Message class where I created an inner class that extended ArrayList, that would associate the Message to each MetaData element.

 static class MessageMetaDataList extends java.util.ArrayList<MessageMetaData> {
  private Message message;
  
  public MessageMetaDataList(Message message) {
   super();
   this.message = message;
  }

 

  public void add(int index, MessageMetaData element) {
   element.setMessage(message);
   super.add(index, element);
  }
  
  public boolean add(MessageMetaData o) {
   o.setMessage(message);
   return super.add(o);
  }

 

  public boolean addAll(Collection<? extends MessageMetaData> c) {
   for (Iterator iter = c.iterator(); iter.hasNext();) {
    MessageMetaData mmd = (MessageMetaData) iter.next();
    mmd.setMessage(message);
   }
   return super.addAll(c);
  }
 }

 

And I would then make certain that a passed in List of MetaData was properly associated.

 public void setMetaData(java.util.List<MessageMetaData> messageMetaData) {
  this.metaData.addAll(messageMetaData);
 }

 

This is where the problem lies. By accessing the passed in List the SQL Statement was executed and loaded all associated objects. Clearly this will not work so I can't think of a clean way to support a bi-directional relationship.

 

Any suggestions?

---

From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Sent: Thursday, May 24, 2007 10:25 PM
To: [EMAIL PROTECTED]; user-java@ibatis.apache.org
Subject: RE: Lazy Loading not working

Yes I do. The interesting thing is that Lazy loading is working on some of my other objects but not on this one.

---

From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of "Larry Meadors" <[EMAIL PROTECTED]>
Sent: Thursday, May 24, 2007 8:12 PM
To: user-java@ibatis.apache.org
Subject: Re: Lazy Loading not working

Do you have cglib on your classpath?

Larry


On 5/24/07, [EMAIL PROTECTED]
<[EMAIL PROTECTED]>wrote:
>
>
> I've got one SQLMap for an object that has children. For some reason when I
> execute a select and have properties of the result object perform selects to
> retrieve the adjacent objects the lazy load does not seem to work, but
> rather the adjacent select statements are being fired and the data is
> retrieved.
>
> I'm using iBatis 2.3.0.667
>
> My SQL Map Config has the following defined:
>
> > cacheModelsEnabled="true"
> errorTracingEnabled="true"
> enhancementEnabled="true"
> lazyLoadingEnabled="true"
> maxSessions="250"
> maxTransactions="30"
> maxRequests="500"
> useStatementNamespaces="true"/>
>
> My result Map looks as follows: (The ones in red seem to be fired every time
> no matter what)
>
>
>
>
>
> > property="previousState" />
> > jdbcType="VARCHAR" property="documentIdentifier"/>
> > jdbcType="VARCHAR" property="poNumber"/>
> > select="RequestOrder.findByPrimaryKey"/>
> > property="createDate" />
> > property="modifiedDate" />
> > />
> > column="{textPointer=Payload_text_pointer,dataLength=Payload_data_length}"
> property="payload" select="Message.loadContent"/>
> > select="Message.findByPrimaryKey"/>
> > select="MessageMetaData.findByMessageId"/>
>
>
>
> Thanks for the help...
>
>
> Chris Mathrusse
> [EMAIL PROTECTED]
> (925) 236-5553
>