[internship] processing time

background ：
There is a push task in the requirement Scheduling time Need to be advanced Push time 30 minute , So you need to subtract... From the push time 30 minute .
Push time -pushDate yes String type .

First thought - Hours minus 1, Minutes are directly set to 30：

However, if the modification time is involved later, you may forget that it has been modified here , So you should subtract 30 Minutes is implemented as a method .

            String[] pushDateArr = marketing.getPushDate().split(":"