title: Entering the second knowledge level of jenkins-scripted-pipeline
body: <p>It is easy to find simple examples for declarative or scripted pipeline. But when the point comes where you go deep into scripting you need so much more information. When you're not familiar to the world of web, java and groovy you are running out of questions which can be asked to go future. Googeling helps you find some magic "hudson.model.Hudson..." or .methods and e.g. @NonCPS-operators solutions. Those solutions work, but I'm searching for the bigger context to work my self from the bottom up. Not from the top down. I'm looking for the knowledge, which is obvious to the insiders.</p>
  
  <p><strong>I'm looking for links/books/api-references or introductions</strong> to learn to find the entrance to knowledge around the jenkins scripted pipeline. e.g. like <a href="https://github.com/jenkinsci/workflow-cps-plugin/blob/master/README.md#technical-design" rel="nofollow noreferrer">this</a> one =).</p>
  
  <p><em>I am not looking for answers to those questions below from the stackoverflow communety. This would be to much! I am looking for links of documentation to get deep into the topic. I assume that for an insider it's insider knowledge is not obvious. So I'm stating here some questions to make it obvious what I would describe as insider knowledge.</em></p>
  
  <h3>Example questions:</h3>
  
  <ul>
  <li>like : "hudson.model.Hudson..." but where do I get those magical dot.separated strings?</li>
  <li>Is there a documentation of the Jenkins Api?</li>
  <li>How can I find documentation of the classes and methods usable in jenkins like e.g. <code>X.Y.collect</code>?</li>
  <li>Is there a way to debug a pipeline?</li>
  <li>Is there a faster way in testing code than every time run it in a pipeline?</li>
  <li>How does the inner mechanism work? </li>
  <li>Is the Knowledge more about groovy or is it about general Jenkins? Or is it java?</li>
  <li>Why <code>println MyArrayList.getClass()</code> <code>class java.util.ArrayList</code> which is a java class? does grooy inherit the types from java, or does the pipeline inherit the types from jenkins, which is java?</li>
  <li>...</li>
  </ul>