I did my Sun Certification last year [2009] and successfully cleared the exam . I am sharing you the materials that i referred to clear it . From my experience clearing the exam is not difficult you just need to mug up the dumps . But i wouldn’t recommend that as you wont get the basics concepts of Java . According to me just read the book KATHY SEIRRA 1.5 twice so that you would get the basic concepts in Java Programming and then go for the dumps . The dumps are so confusing that many questions would look alike but would be having different answers , go through dumps as much as you can . Out of 72 questions i got 71 correct answers out of which more than 60 questions where from these dumps provided below .

Excellent Books for Java Certification

Sun Certified Programmer for Java 5: Study Guide Exam 310-055 Kathy Sierra,Bert Bates.

A Programmer’s Guide to Java SCJP Certification Java 5 : Khalid A Mughal , Rolf A Rasmussen.

SCJP Certification Tutorial | SCJP Dumps

Sun 310-055 Sun Certified Programmer for the Java 2 Platform.SE 5.0 362 Q&A Version 2.29

Sun Certified Programmer for the Java 2 Platform, Standard Exam 310-055 Edition 5.0

Troytec Testkiller – 224_answers – explaination Edition 5.0

Troytec Testkiller – 224 qn set – Drag and Drop Answers Edition 5.0

Sun Certified Programmer for the Java 2 Platform.SE 5.0 Exam: 31 0-055 Edition: 6.0

Hope it helped you a lot to get an idea of materials to reffer !