Connect to a Service on Startup¶

One common request when people make there own custom application - is making sure their PostGIS (or WFS or whatever) is available and added to the Catalog when the user first starts up.

Catalog
net.refractions.udig.community.jody.tile

(example that adds a custom service on startup)

Add an Eclipse “Startup” extension that adds¶

Here is the part of the plugin.xml used in the above example:

<extension
         point="org.eclipse.ui.startup">
      <startup class="net.refractions.udig.community.jody.tile.Preload"/>
   </extension>

Implement an IStartup

/**
 * Used to preload some nice datasets (ie worldwind).
 */
public class Preload implements IStartup {
    public void earlyStartup() {
        Map<String,Serializable> params = new HashMap<String,Serializable>();
        params.put( "url", WorldWindTileProtocol.class.getResource("earthimages.xml") );

        List<IService> match = CatalogPlugin.getDefault().getServiceFactory().acquire( params );
        if( !match.isEmpty()){
            IService service = match.get(0);

            ICatalog local = CatalogPlugin.getDefault().getLocalCatalog();
            local.add( service );
        }
    }
}

Improvements¶

This example is pretty simple - to be a bit more correct we should check if the IService is already in the catalog:

IService found = catalog.getById( IService.class, service.getIdentifier(), progressmonitor );
if( found != null ){
   return; // already loaded!
}
ICatalog local = CatalogPlugin.getDefault().getLocalCatalog();
local.add( service );

Normally you also check the service to see if it is working - see the Catalog page for details.

Connection Parameters¶

There are two good approaches to acquiring connection parameters for these “required” services.

Preferences

Store the connection parameters in preferences; make a preference page so they can change the host / port / etc...

Login

Make a login screen that the user can fill in their credentials.

uDig

Connect to a Service on Startup¶

Add an Eclipse “Startup” extension that adds¶

Improvements¶

Connection Parameters¶