Ditto Kevin's comment...its nice to see someone making the initiative to write tutorials, but if you are going to do so:
a) spend some time with it - make it legible, compilable, readable, use proper syntax, use proper grammar, use proper code conventions, use javadoc commenting, etc... and most importantly, make it so anyone can follow it. Make it look 'textbook' (and no offense, but the above is far from achieving any of these points) - if you want someone to take them with authority and follow them, they have to be made to look like they were written by a teacher, not a student.
b) write something that has not been done ad nauseum
- there are countless demonstrates of 'hello world', and there are the standard java tutorials that most people will navigate to which Kevin pointed out. Think a bit outside the box and write things unique to distinguish them away from the rest.