Using nd-extension)

In the example of customer banking, how can we not proceed? The following error occurs:Object type cannot be converted to target type.

What I want to do is: I have slightly changed the requirements. The customer and bank are no longer one-to-one, but one-to-one.
In the configuration file, change it:

Customer. HBM. xml

<Bag name = "customerbanks"

Cascade = "all"

Order-by = "bankname ASC">

<Key column = "customerid"/>

<One-to-operate class = "data. Bank, data"/>

</Bag>

 

Bank. HBM. xml

<Role-to-one name = "bankcustomer" class = "data. Customer, data"

Cascade = "all" outer-join = "Auto"

Column = "customerid"

Not-null = "false"/>

Detailed configuration files, domain model, and DB model are downloaded here!
Then I want to insert the bank at the same time when inserting the customer. The implementation code is as follows:
Customer acustomer = new customer ();

Acustomer. customertitle = "Developer ";

Acustomer. customerage = 25;

Acustomer. updatetimestamp = datetime. now;

 

Bank abank = New Bank ();

Abank. bankname = "CICB ";

Abank. banlance = 1233453.234 m;

Abank. updatetimestamp = acustomer. updatetimestamp;

 

// Bind the two object to each other.

Abank. bankcustomer = acustomer;

Acustomer. customerbanks. Add (abank );

 

Aentityrule. Save (acustomer );

Why is an error, Object type cannot be converted to target type.

I used SQL profile to check and found that no SQL statements were generated at all. Please give me some advice on what went wrong.