code: private Asset getAsset(Object id, String assetTypeToken) {
          Asset result = assetCache.get(id);
  
          if (result == null) {
              try {
                  IAssetType assetType = getMetaModel().getAssetType(
                          assetTypeToken);
  
                  if (id instanceof AssetID) {
                      AssetID assetId = (AssetID) id;
                      result = new Asset(Oid.fromToken(assetId.getToken(),
                              getMetaModel()));
                  } else {
                      result = new Asset(assetType);
                  }
                  setAsset(id, result);
              } catch (OidException e) {
                  throw new ApplicationUnavailableException(e);
              }
          }
          return result;
      }
docs: Find an asset in the asset cache or create one for this id.
  
  @param id             asset will be found for.
  @param assetTypeToken The Asset Type Token of the asset to create if one
  does not already exist.
  @return An Asset that will exist in the asset cache.