How to abstract colums from persistable class(s)

for example, i have some common column (created, modified, etc) for all
tables and i don't want to mape the common columns in every single class.
i know kodo has the following restriction in Inheritance
"If a persistent class inherits from a non-persistent class, the fields
of the non-persistent superclass cannot be persisted"
is there any workaround for this, can any one help me
Thanks

That's no longer a restriction -- you can do what you indicated by using
Kodo's horizontal mapping support.
-Patrick
kailasam.k wrote:
for example, i have some common column (created, modified, etc) for all
tables and i don't want to mape the common columns in every single class.
i know kodo has the following restriction in Inheritance
"If a persistent class inherits from a non-persistent class, the fields
of the non-persistent superclass cannot be persisted"
is there any workaround for this, can any one help me
Thanks

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How to load function from derived class from dll

Dear all,
how to access extra function from derived class.
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virtual ~CMyIShape(){};
virtual void Fn_DrawMe(){};
// =========== this is ShapRectangle.dll
//==========================ShapRectangle .h
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in exe there is no include header of of ShapCircle and ShapRectangle
and from the exe i use LoadLibrary and GetProcAddress .
typedef CMyIShape* (*CREATE_OBJECT) ();
CMyIShape*xCls ;
//===================== from ShapeCircle.Dll
pReg= (CREATE_OBJECT)GetProcAddress (hInst ,"CreateShape");
xCls = pReg();
now xCls give all access of base class. but how to get pointer of funciton Fn_GetRadious() or how to get access.
thanks in advance.

could you please tell me in detail. why so. or any reference for it. i love to read.
i don't know this is bad way.. but how? i would like to know.
I indicated in the second sentence. Classes can be implemented differently by different compilers. For example, the alignment of member variables may differ. Also there is the pitfall that a class may be allocated within the DLL but deallocated in the client
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is there any other way to archive same goal?
Of course. DLL functionality should be exposed as a set of functions that accept and return POD data types. "POD" means "plain-ole-data" such as long, wchar_t*, bool, etc. Don't pass pointers to classes.
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and why i need to give header file of ShapCircle and shapRectangle class, even i am not using in exe too. i though it is enough to give only MyIShape.h so with this any one can make new object.
Indeed you don't have to, if you only want to call the public properties and methods that are defined within MyIShape.h.

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import javax.microedition.lcdui.*;
import java.io.*;
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Here is the example:
public abstract class AbstractClass{
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protected abstract double abstractMethod();
public class RealClass extends AbstractClass{
public double abstractMethod(){
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Error message:
RealClass should be declared abstract; it does not define abstractMethod() in AbstractClass

I also compiled the code with Jdk1.3 and it
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How can I casting from parent class to children class

Dear,
Could someone help me to casting from parent class to children class.
I have class like this
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Hello
This is for the experts.
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Edited by: 875864 on 30-Oct-2011 15:05

875864 wrote:
Hello
This is for the experts.
What is the best approach to passing a large set of data from Class A to Class B? I have a DAO Class that connects to a database to retrieve data. I tried saving the data in a collection (map) and passing the collection to Class B. The problem here is that the data is may be too large for a collection without increasing the heap size, it could cause out of memory exception. Instead I'd like to pass the data (row by row) on to the "Controller" Class where which will process each row. I am not sure how to do this without using a collection or some sort. Some tips will be much appreciated.
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Thanks
Edited by: 875864 on 30-Oct-2011 15:05if its a large set of data, and is fetched from DB and you are sure that it is too large and chances of getting out of memory exception then why you are passing it over request.
If the data is fetched based on some filter criteria, then just pass the filter criteria from class A to class B, and fetch the data from DB based on the filter criteria in class B.

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How to access variables from other class

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How get controls name from a class private data?

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Thanks.
Solved!
Go to Solution.

You are already making the overriding method just because you have to write to the Bundle By Name. And then how are you going to handle all of the data types the keys could be. You are making things more difficult than it should be for really very little benefit.
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How to access function from Top Class to Function of class that contain the the member variable of TopClass

Dear All,
is there any way that i can access function or member variable of aggregate class.
i am working in Visual Studio 2010
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class aaa : public BaseClass
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int Index;
char *cName;
void doSometing()
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long lSize;
long color;
void doSometing();
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Dear All,
is there any way that i can access function or member variable of aggregate class.
i am working in Visual Studio 2010
and making win32 dll with mfc Support. i am new in dll system. just learning and doing.
previously all in exe and i am working this like
CTestDoc*pDoc = (CTestDoc*)GetTestDocument();
somevar = pDoc->xDoc.mVar.GetValue ();
now i am trying to put all in dll. so getting problem
What problem?
The rules of C++ do not change because some of the code ins in a DLL. But the classes in a DLL need to be exported. See for example
https://msdn.microsoft.com/en-us/library/81h27t8c.aspx
You should also supply a macro so that the class header can be used in both the DLL and the client. See for example
http://stackoverflow.com/questions/14980649/macro-for-dllexport-dllimport-switch
If you exchange memory between the DLL and the client (as your example will do, because of the std::vector content), you should also be sure to use the same version of the compiler for each module, and to dynamically link to the CRT.
I would also advise you to start with a less complicated scenario, with just one DLL.
David Wilkinson | Visual C++ MVP

How to abstract colums from persistable class(s)

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