How to programmatically get the PDC status of a Story / Defect fix workitem in ALM
One answer
I do not know what a pre delivery check status is and how it is represented in your process. So there is no way to tell you. The code would not help you in any case.
https://github.com/jazz-community/work-item-command-line is an example for pretty much any client work item operation you want to use.
https://rsjazz.wordpress.com/2013/01/02/working-with-work-item-attributes/ shows how to work with the most common work item attribute types. As a prerequisite follow https://rsjazz.wordpress.com/2015/09/30/learning-to-fly-getting-started-with-the-rtc-java-apis/ and run lab 1 of the Extensions Workshop to set up a development workspace. The last part of the lab 1 explains how to install the plain java client libraires.