Mostly Harmless: java Exception - Unknown Source

Many time java engineer is in dilema of exception called Unknown Source and it take
hours and some whole day to track the source of exception by tracking entire code flow

Here is very good tips to tackle from such kind of error, it is basically because of
ant level configuration in build.xml

Please visit Nilesh Bansal blog for more details insight on it

Mostly Harmless: java Exception - Unknown Source

Happy Debugging