title: How to generate API Documentation using openapi-generator?
body: <p>I'm new to the <code>OpenAPI</code> 3.0.0. </p>
  
  <p>I have successfully created a java client library using an <strong>openapi-generator</strong>. </p>
  
  <p>But <code>OpenAPI</code> Generator allows the generation of API client libraries (SDK generation), server stubs, documentation. So I want to know is there any commands or steps are available to generate HTML documentation and also to customize the documentation template. </p>