Many components of one type in persistent class

Ziaw · **Joined:** Thu Jul 21, 2005 7:24 am **Posts:** 2

I have a class to be mapped as a component that contains several properties, for example, DAY, MONTH and YEAR. The class is decoreated
with [Component()] attribute.

In a master-class I have several properties of this type each decorated
with [ComponentProperty()].

Code:

[Component()]
public class MyComponent
{
  [Property()]
  public int Days
  {get {...};set {...};}
  [Property()]
  public int Months
  {get {...};set {...};}
  [Property()]
  public int Years
  {get {...};set {...};}
}

[Class()]
public class MyPersistentClass
{
  [ComponentProperty]
  MyComponent OneProp
  {get {...};set {...};}

  [ComponentProperty]
  MyComponent TwoProp
  {get {...};set {...};}

  [ComponentProperty]
  MyComponent ThreeProp
  {get {...};set {...};}
}

As a result, all three properties "Days" from "OneProp","TwoProp" and "ThreeProp" are mapped to the same DB column. That is also true for "Years" and "Months".
Unfortunately, I have found no ways to specify different columns in [ComponentProperty()] .

KPixel · **Posted:** Thu Dec 08, 2005 11:19 am

The only solution I can think of is to do:

Code:

[Component()] // These attributes become optional
public class MyComponent
{
  [Property()]
  public int Days
  {get {...};set {...};}
  [Property()]
  public int Months
  {get {...};set {...};}
  [Property()]
  public int Years
  {get {...};set {...};}
}


[Class()]
public class MyPersistentClass
{
  MyComponent OneProp
  {get {...};set {...};}

  [Component(Name="OneProp")]
  public class MyComponent_OneProp
  {
    [Property(Column="Days_OneProp")]
    public int Days
    {get {...};set {...};}
    [Property(Column="Months_OneProp")]
    public int Months
    {get {...};set {...};}
    [Property(Column="Years_OneProp")]
    public int Years
    {get {...};set {...};}
  }

  ...
}

Ziaw · **Joined:** Thu Jul 21, 2005 7:24 am **Posts:** 2

And what shall i do with many functions in my program taking MyComonent arguments?

Code:

class MyComponent
{
   public virtual Prop
  {
     get{...}set{...}
  }
}
[Class]
class MyClass
{
   [Component]
   class OneMyComponent: MyComponent
   {
       [Property(Column="ONECOMP_ONEPROP")]
       public override Prop
       {
           get {return base.Prop;}
           set {base.Prop = value;}
       }
   }
   
  [ComponentProperty()]
  OneMyComponent OneComp
  {
     get{...}set{...}
  }
}

right?

KPixel · **Posted:** Sat Dec 10, 2005 4:35 am

Two little corrections:

Code:

class MyComponent
{
   public virtual Prop
  {
     get{...}set{...}
  }
}

[Class]
class MyClass
{
   [Component(Name="OneComp")]
   class OneMyComponent: MyComponent
   {
       [Property(Column="ONECOMP_ONEPROP")]
       public override Prop
       {
           get {return base.Prop;}
           set {base.Prop = value;}
       }
   }

  OneMyComponent OneComp
  {
     get{...}set{...}
  }
}

Mapped classes (components, subclasses) which are nested in another mapped parent class are automatically included in the mapping of this parent class; so if you use [ComponentProperty], you will have this information twice in the mapping.