code: @BetaApi
    public final Operation setUrlMapTargetHttpProxy(
        String targetHttpProxy, UrlMapReference urlMapReferenceResource) {
  
      SetUrlMapTargetHttpProxyHttpRequest request =
          SetUrlMapTargetHttpProxyHttpRequest.newBuilder()
              .setTargetHttpProxy(targetHttpProxy)
              .setUrlMapReferenceResource(urlMapReferenceResource)
              .build();
      return setUrlMapTargetHttpProxy(request);
    }
docs: Changes the URL map for TargetHttpProxy.
  
  <p>Sample code:
  
  <pre><code>
  try (TargetHttpProxyClient targetHttpProxyClient = TargetHttpProxyClient.create()) {
  ProjectTargetHttpProxyName targetHttpProxy = ProjectTargetHttpProxyName.of("[PROJECT]", "[TARGET_HTTP_PROXY]");
  UrlMapReference urlMapReferenceResource = UrlMapReference.newBuilder().build();
  Operation response = targetHttpProxyClient.setUrlMapTargetHttpProxy(targetHttpProxy.toString(), urlMapReferenceResource);
  }
  </code></pre>
  
  @param targetHttpProxy Name of the TargetHttpProxy to set a URL map for.
  @param urlMapReferenceResource
  @throws com.google.api.gax.rpc.ApiException if the remote call fails