This book attempts to teach Java from scratch and does not do very good job of it. There are a number of technical errors and questionable statements such as: 'As soon as a return is performed in a Java function, the method invocation ends' (that is not true if there is a 'finally' clause).
The rest of the book does not appear to be so bad, although I haven't checked everything. It is designed as a textbook for a university-level course on data structures and algorithms and their efficiency and some parts assume an advanced-level knowledge of mathematics. The coverage is what you might expect from a course, but I was surprised to find that Huffman is the only compression algorithm described.
I'm not sure whether I would recommend this book as a replacement for whatever the lecturer recommends; it might not make things any clearer. I wouldn't recommend it as a reference either because it sometimes defines and uses non-standard terminology that could be unclear if you haven't read from the beginning. Overall the book is reasonable, but I'm sure there are better data structures and algorithms books out there.