public void unloadAll() {
		this.logger.logInfo(LOGGING_SOURCE, "unloading resources");
		for (ResourceHandle handle : this.resourceMap.values()) {
			if (handle.isLoaded()) {
				try {
					handle.unload(getCore());
					this.logger.logDebug(LOGGING_SOURCE, "unloaded resource: " + this.invResourceMap.get(handle));					
				} catch (ResourceException e) {
					this.logger.logWarning(LOGGING_SOURCE, "unable to unload resource: " + e.getMessage());					
				}
			}
		}
	}