public Builder clearApiKeyConfig() {
      if (apiKeyConfigBuilder_ == null) {
        if (authConfigCase_ == 1) {
          authConfigCase_ = 0;
          authConfig_ = null;
          onChanged();
        }
      } else {
        if (authConfigCase_ == 1) {
          authConfigCase_ = 0;
          authConfig_ = null;
        }
        apiKeyConfigBuilder_.clear();
      }
      return this;
    }
<pre>
The API secret.
</pre>

<code>.google.cloud.vertexai.v1.ApiAuth.ApiKeyConfig api_key_config = 1;</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/ApiAuth.java