code: public final J4pClientBuilder useProxyFromEnvironment(){
          Map<String, String> env = System.getenv();
          for (String key : env.keySet()) {
              if (key.equalsIgnoreCase("http_proxy")){
                  httpProxy = parseProxySettings(env.get(key));
                  break;
              }
          }
          return this;
      }
docs: Set the proxy for this client based on http_proxy system environment variable