What is "illegal character: \ufeff" in Java?

Question

Java noticed me a problem at the begin of the first row and I don't know what to do.
I tried to copy the class in another project but the trouble was the same.
I see no character before the code, i thought this is a special character so I've to delete something somewhere but I can't figure out where and what.

Answer 1

this one of the common error you get when you copy the code from different platform which uses different charset so you may need to convert the charset of the codr so that editor to recognize the code