Design mode 4
In the design mode 3 we see how to make the bean from Struct
The grouped water and all fields can be defined as a CMP field. Here, we can
Reduce the amount of code in further correcting the implementation of setData () and getData ().
We add a method for this Structure.
Value Object Code Snippet for Company
Public Class CompanyStruct IMPLEMENTS
Java.io.serializable {
Public Integer Comid;
Public String COMNAME;
Public String Comdescription;
Public TimeStamp MutationDate;
Public void copyfrom
Comid = struct.comid;
COMNAME = Struct.Comname;
COMDESCRIPTION = Struct.comDescription;
MutationDate = struct.mutationdate;
}
}
Since the entry bean is inherited from Struct, the implementation class in Bean
The same can be referenced in the CopyFrom () method, of course, it must be noted that
This CopyFrom () method is not a business method, it doesn't need to be in Bean
Remote interface is exposed to the caller.
Now, getData () and setData () methods can simplify further simplification.
Code snippet for an entry bean's getdata ()
Public companyStruct getdata () {
Companystruct result = new companyStruct ();
Result.copyfrom (this);
Return Result;
}
Here, THIS is incorporated into CopyFrom (). Because of ENTTITY Bean
Inheriting from Struct, so this entitty bean can be used as a
Struct is incorporated.
The EJB container does not agree with the THIS pointer as a parameter because of two controls
An instance of a BEAN in the thread can also cause a transaction conflict. But things
In fact, we did not violate this principle because we didn't
The reference to the BEAN transmits this and does not reference any ways that may cause a transaction conflict.
Code snippet for an entry bean's setdata ()
Public void setdata (Companystruct Struct) {
this.copyfrom (struct);
}
Similarly, the above method assigns the value of the Stru to ENTTITY Bean.
This implementation is an Entity Bean that maps to have a lot of columns.
The advantage of the method is that the code of the bean implements the class is very simple. This setting
The meter is greatly enhanced to make the code and its streamline, readability and maintainability.
All modifications to any database only need to modify the Struct as the base class, while
Don't need to modify the BEAN's code. Separate this change from struct,
The deployment descriptor needs to be modified when the CMP field changes. This makes it
It is better to adapt to the design changes.
Here, there is still no relationship between the bean, which will be solved in the design mode 5.
