I dont know is it usful? Its now Oracle , not SUN ,please tell me whether this book wil be helpful for exam?Thanks!

yes. it's by far the best series of books I've encountered for those certifications.

Oracle changed the name of the certification, not the contents. of course, if you 'll go for the Java 7 exam, you should also look into the new material, but for Java 6 exam, that book is what you want . (and the material for Java 7 isn't that much different)

yes, it's by far the best series for those certifications I've encountered.

Oracle may have changed the name of the certificat, they didn't changed the material covered.

for the Java 7 exam, you'll need to read up on the additional material (which isn't that much), but otherwise, that book is what you want.

of course a lot depends on whether you know Java or not... The book assumes you do, a lot of punters try to get through the exam who don't, and just want some cram sheet and "the dumps", which this book will not provide you with.