HaspMap

Interfacet Map har to implementationer HashMap og TreeMap.

Map m<X,Y> = new HashMap<X,Y>();
HashMap m<X,Y> = new HashMap<X,Y>();
Map m<X,Y> = new TreeMap<X,Y>();
TreeMap m<X,Y> = new TreeMap<X,Y>();

virker alle, men:

TreeMap m<X,Y> = new HashMap<X,Y>();
HashMap m<X,Y> = new TreeMap<X,Y>();

virker ikke.

Hvis jeg skulle gaette paa din kode:

TreeMap functionResources = (TreeMap) ((Map) AbstractParameterManager.getResource(resourceId)).get(function);

->

Map functionResources = ((Map) AbstractParameterManager.getResource(resourceId)).get(function);

og:

functionResources = new TreeMap();

->

functionResources = new HashMap();

Hm, synes ikke jeg kan få det til at fungere. Der kommer llidt mere kode nedenfor:

public abstract class AbstractParameterManager implements ParameterManager {
    protected static final Map resourceLocations =
        ResourceLocator.locateResources();
    protected static final Map resources = new TreeMap();
    protected final Map overrides = new TreeMap();

   
    protected static Object getResource(String resourceId) {
        Map resourceMap = (Map) resources.get(resourceId);
        if (resourceMap == null) {
            resourceMap = new TreeMap();
            resources.put(resourceId, resourceMap);
        }
        return resourceMap;
    }
   
    protected static Map getResource(String resourceId, String function) {
        TreeMap functionResources = (TreeMap) ((Map)
                AbstractParameterManager.getResource(resourceId)).get(function);
        if (functionResources == null) {
            functionResources = new TreeMap();
            ((Map)
                      AbstractParameterManager.getResource(resourceId)).put(function,
                      functionResources);
        }
        return functionResources;
    }