code: public CredentialsProvider setProxyAuthentication(ProxyConfig proxyConfig) {
  
  		if (proxyConfig == null) {
  			return null;
  		}
  		String username = proxyConfig.getUsername();
  		String password = proxyConfig.getPassword();
  
  		if (!username.isEmpty() && !password.isEmpty()) {
  			String host = proxyConfig.getHost();
  			String port = proxyConfig.getPort();
  			if (!host.isEmpty() && !port.isEmpty()) {
  				CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
  				String domain = proxyConfig.getDomain();
  				if (!domain.isEmpty()) {
  					credentialsProvider.setCredentials(new AuthScope(host, Integer.parseInt(port)), new NTCredentials(username, password, host, domain));
  				} else {
  					credentialsProvider.setCredentials(new AuthScope(host, Integer.parseInt(port)), new UsernamePasswordCredentials(username, password));
  				}
  				return credentialsProvider;
  			}
  		}
  		return null;
  	}
docs: Method to set proxy authentication
  
  @return