ical4j parsing perfomance

ical Calendar parsing is slow.

I saw that you are using ical4j version 1.0-rc3-atlassian-8.

I have an example ics file with ca. 300 VEVENTs. Parsing it takes ca. 7s on my laptop.
Parsing it with any ical4j version >= 1.0 takes 450-600ms.

I suggest you look at merging back (at least some of) the improvements in the ical4j mainline.

I realise your customisations may make that difficult. Please at least look at integrating this straightfoward 3-line change that avoids useless expensive Calendar creation: https://github.com/ical4j/ical4j/commit/b4215c3d3559afbfc1530e4121708e8c61f0d18e

In my tests that alone cut 2/3 off the parsing time of your ical4j version.