I read the two books for my exam 1Z0-899.
The two books cover the exams.
But most of the exam is based on the
Java EE5, basics functionality of the Servlets and
JSP Technology.
On the new additions to the Java EE6, which you find in the book OCEJWCD Study Companiom, Chapters 8, 10,11,12.
My finally advice.
Read one of the books twice, and practice a lot with examples.