code: public boolean isWebSocketUpgrade() {
  		if (!getResponseHeader().isEmpty()) {
  			String connectionHeader = getResponseHeader().getHeader("connection");
  			String upgradeHeader = getResponseHeader().getHeader("upgrade");
  			
  			if (connectionHeader != null && connectionHeader.equalsIgnoreCase("upgrade")) {
  				if (upgradeHeader != null && upgradeHeader.equalsIgnoreCase("websocket")) {
  					return true;
  				}
  			}
  		}
  		
  		return false;
  	}
docs: ZAP: New method checking for connection upgrade.
  
  @return True if this connection should be upgraded to WebSockets.