Error throwed when using ajax with json object

Hi,

I have a hkptu.json file. And I am using DataTable ajax with json object but when it load the json file, it throwed error as below.

Uncaught TypeError: Cannot read property 'length' of undefined
at jquery.dataTables.min.js:48
at i (jquery.dataTables.min.js:35)
at Object.success (jquery.dataTables.min.js:35)
at i (jquery.min.js:2)
at Object.fireWith [as resolveWith] (jquery.min.js:2)
at A (jquery.min.js:4)
at XMLHttpRequest.<anonymous> (jquery.min.js:4)