Re: Design Question

Hi Michael,

Michael Deninger wrote:
> I have a design question that I would like to bounce off some of you  
> more experienced WO developers..
> 
> I have some static data that I need to access from within an  
> EOGenericRecord. The data, unfortunately, is not in the DB (and even  if 
> it were, creating a relationship to the entity would likely not  work 
> for various reasons). The data is essentially a dictionary of  keys / 
> values that describe the meaning of the coded values in one of  the 
> database tables. E.G.
> 
> Entity: PatientAllergy
>     Attribute: AllergyCode
> 
> where AllergyCode is some number (say 83). The meaning of that number  
> is in this dictionary (e.g. value = 83, description = "penicillins")
> 
> What is the best way to accomplish this? I have considered the  following:
> 
> 1) read this dictionary into my Application object at startup. Sounds  
> great, but I cannot figure out how to access EOApplication from an  
> EOGenericRecord


WO can load a properties file for you, so you could read in the data in 
the application constructor and store it in a static. Then you can 
access it as Application.myDictionary, but this is poor style from the 
EO's. Maybe something like the following instead:

//NOTE: untested code

import com.blah.blah.Lookup.Foo;
public Application() {
   super();
   //Read xyz from somewhere. eg) Properties.
   Foo.s = "xyz";
}


package com.blah.blah.Lookup;
public class Foo {
   //dictionary would be better for multiple.
   public static String s = null;
}

import com.blah.blah.Lookup.Foo;
public Bar extends EOGenericRecord{

   //Use a dictionary for multiple.
   private String fooValue;
   private void loadFoo(){
      if(fooValue == null){
         fooValue = Foo.s;
      }
   }

   awakeFromFetch(...){
      loadFoo();
   }

   awakeFromInsertion(...){
      loadFoo();
   }
}


HTH.
cheers,
  - shaun