[dtp-dev] Fine-grained refresh control on ICatalogObject

[Hui.Cao@xxxxxxxxxx]

Hi,
        In
DSE, when user invokes "Refresh" on a folder, the parent ICatalogObject.refresh()
will be called, resulting in all other folders under the same ICatalogObject
are refreshed as well. Is there a reason to do so? How about adding a "refresh(int
flag)" method to allow fine-grained refresh control? In this way only
the desired objects are refreshed.
        Another
question is about whether to reserve the old objects while loading in catalog
loader. I have seen the following pattern in WTP RDB catalog loaders (please
notice the bold part):
        private
synchronized
void
loadSchemas() {
         
      if(this.schemasLoaded)
return;
         
      EList schemaList = super.getSchemas();
         
      Object[] oldList = schemaList.toArray();
         
      boolean
deliver = this.eDeliver();
         
      this.eSetDeliver(false);
       
         
      try
{
         
              List list
= CatalogUtils.getDBSchemas(this.dbName,
this.connection);
         
              for
(int
i = 0; i < list.size(); i++) {
         
               
      final
String schemaname = (String) list.get(i);
         
               
      
         
               
      Schema schema;

         
               
      EClass metaclass= SQLSchemaPackage.eINSTANCE.getSchema();

         
               
      Object element = CatalogSchema.findElement(oldList,schemaname,metaclass);

         
               
      try
{
         
               
              if
(element != null)
{
         
               
               
      schema = (Schema) element;
//we must put list.add before refresh,
otherwise NPE will be thrown
         
               
               
      schemaList.add(schema);
         
               
               
      ((ICatalogObject)schema).refresh();
         
               
              } else
{
         
               
               
      schema = new
CatalogSchema();
         
               
               
      schema.setName(schemaname);
         
               
               
      schemaList.add(schema);
         
               
              }
         
               
      
         
               
      } catch
(ArrayIndexOutOfBoundsException e) {
         
               
              //
do nothing
         
               
              e.printStackTrace();
         
               
      } catch
(NullPointerException e) {
         
               
              //
do nothing
         
               
              e.printStackTrace();
         
               
      }
         
              }
         
              this.schemasLoaded
= true;
         
      }
         
      catch
(Exception e) {
         
              System.out.println(e.toString());
         
      }
         
      this.eSetDeliver(deliver);
        }

That is, the catalog loader tries to
reserve the old object references. I suppose this is to make sql model
objects referenced by other components (such as schema object editor) valid
after refresh, it that true? 

Best Regards!

Max ( Hui ) Cao
Sybase, Inc. Shanghai, China