A very clear book, very explicit, perfectly accessible to anyone who already has a good knowledge of Java, but knows nothing about the functional programming resources available from Java 8 by the novelties are the streams and lambdas. Many examples, diverse, belonging to all kinds of areas and highlighting the new design possibilities now permitted, showing gains clarity of the code, in ease of maintenance and ease of multi-threas programming they offer us. A book in my opinion much more interesting and effective than Warburton's book on the same subject also available on Amazon. If you want to convince you that Java 8 is an impressive leap forward for the language, read this book!