code: public void setFunctions(java.util.Collection<String> functions) {
          if (functions == null) {
              this.functions = null;
              return;
          }
  
          this.functions = new java.util.ArrayList<String>(functions);
      }
docs: <p>
  A list of <code>Function</code> objects.
  </p>
  
  @param functions
  A list of <code>Function</code> objects.