Hi everyone,
I'd be very thankful if anyone could help me with this problem
because I got stuck on it for several weeks.
I'm developing a FDS application with database connection and I've
mapped a relational database to POJO's with Hibernate (using
hibernate tools). I'm experiencing a lot of problems when I try to
insert and delete items using the hibernate assembler. Here is my
situation.
My database, which represents information about cars, contains five
tables:
MODEL
id
engine
transmission
cab
bed
MODEL_PACK
model_id
pack_id
inclusion_type
PACK
id
name
category
MODEL_COLOR
model_id
color_id
COLOR
id
extColor
intColor
The AS classes that represent this schema:
Model.as
id:int;
engine:string;
transmission:string;
cab:string;
bed:string;
colors:ArrayCollection;
packs:ArrayCollection;
ModelPack.as
id:ModelPackId;
model:Model;
pack:Pack;
inclusion:String;
ModelPackId is a custom class to store the composite primary key
which is mapped to the corresponding java POJO.
Pack.as
id:String;
category:String;
name:String;
models:ArrayCollection;
Color.as
id:String;
extColor:String;
intColor:String;
models:ArrayCollection;
The corresponding destinations in data-management-config.xml:
<destination id="models.hibernate">
...........
<many-to-many property="colors"
destination="colors.hibernate" lazy="false"/>
<one-to-many property="packs"
destination="ModelsPacks.hibernate" lazy="true"/>
..............................
<destination id="colors.hibernate">
.............................
<many-to-many property="models"
destination="models.hibernate" lazy="true"/>
....................................
<destination id="ModelsPacks.hibernate">
....................
<identity property="id"
type="com.fds.proyecto.hibernate.ModelPackId"/>
<many-to-one property="model"
destination="models.hibernate" lazy="true"/>
<many-to-one property="pack"
destination="packs.hibernate" lazy="true"/>
...................
<destination id="packs.hibernate">
...................
<one-to-many property="models"
destination="ModelsPacks.hibernate" lazy="true"/>
.....................
As you can see the relationships are bidirectional.
For example I have the data service to manage the operations in the
front end and a datagrid:
<mx:DataService id="models_ds" destination="models.hibernate"
result="handleResult(event)"/>
<mx:DataGrid id="modelList" dataProvider="{models_ac}"/>
and a button:
<mx:Button label="Delete" id="btnDelete" click="delModel()"/>
The callback function only uses the hibernate assembler to delete the
model:
models_ds.deleteItem(modelList.selectedItem);
models_ds.commit();
It seems that the operation is performed succesfully but then when I
check the database or reload the application the model that I've
tried to delete is still there with its corresponding packs and
colors. Sometimes the application throws a runtime error about
synchronization. I've tried to remove the relations in the AS classes
because I think that the problem have to do with the relations
between classes and it works but in this case the application doesn't
meet my requirements and the delete operation is more complex.
Similar problems happen when I try to add Items.
I've tried a lot of solutions to fix that problem (remove relations,
convert them to unidirectional instead of bidirectional...) and I'd
be deeply grateful if anyone can show me the procedure to add and
delete items in that scenario. I've also thought that I could have
missed any tag like "cascade" in the hibernate mapping files but I
haven't tried this solution because I don't know what does it exactly
mean.
I have heard that the hibernate assembler has some bugs and in some
circumstances it doesn't work properly. Could anyone confirm that?If
true what should be the alternative solution? It's very important for
me because this is a small part of my dissertation and I can't
continue because I got stuck on this issue.
Thanks a lot in advance,
Carlos
