Ok so I found this on the internet and thought that this might be really helpful to some people, I am not claiming that I wrote it but it is very useful. This link contains a list of common errors which are repeatedly posted on the plugin development page and so since I found this link i'd like to share it with everyone so people know what all the errors they are getting mean. Link: http://www.dreamincode.net/forums/topic/166879-beginners-fix-your-own-java-errors/