EDIT

package eu.etaxonomy.taxeditor.handler.defaultHandler.e4;

import javax.inject.Named;

public abstract class DefaultOpenHandlerBaseE4 <T> {

    protected IEclipseContext context;

    protected MApplication application;

    protected EModelService modelService;

    @Execute

        this.modelService = modelService;

        this.application = application;

        String commandId = menuItem.getCommand().getElementId();

        Object transientData = menuItem.getTransientData().get(commandId+".uuid");

//            T entity = getEntity(((UuidAndTitleCache)transientData).getUuid());

            open((T)transientData, shell, partService);

        }

    }

    @CanExecute

    protected String getPartId(){

        return null;

    }

}