code: public GetFolderResult withFiles(File... files) {
          if (this.files == null) {
              setFiles(new java.util.ArrayList<File>(files.length));
          }
          for (File ele : files) {
              this.files.add(ele);
          }
          return this;
      }
docs: <p>
  The list of files that exist in the specified folder, if any.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setFiles(java.util.Collection)} or {@link #withFiles(java.util.Collection)} if you want to override the
  existing values.
  </p>
  
  @param files
  The list of files that exist in the specified folder, if any.
  @return Returns a reference to this object so that method calls can be chained together.