title: Not able to read parameters from properties file in jenkins
body: <p>Here is what I am trying to achieve. - I have two 'Choice Parameters' in my Jenkins job. The values of the first Choice Parameter are hard coded. The second choice list should be populated based on the first choice list selection. I have one properties file saved in Jenkins, which has key-value pairs. The values in first choice list and the Keys in the file are same. On selecting a value in first choice list i want a code to read the properties file and populate the second choice parameter with the values from file corresponding to that key. 
  For second choice list i am trying with 'Active Choice Reactive Parameter' , Referenced parameters= first_choice and below groovy script. But this is not returning any values. Please help!</p>
  
  <pre><code> def firstChoice = [first_choice]
   Properties props = new Properties()
   def stream = new FileInputStream('C:/Jenkins/books.properties')
   try{
       props.load(stream)
      }
      catch (Exception ex){
       println "Exception"
      }
      finally {
        stream.close()
      }
   def values = props.getProperty(firstChoice).split(",")
   return values
  </code></pre>