The knowledge needed to write modern input/output (I/O) in Java is contained in this book, which is addressed to advanced Java developers.

The book has two parts: the I/O and the non-blocking I/O (NIO). The I/O part presents in detail the classic Java I/O classes such as file, streams, and reader/writers. The second part is about the newer NIO application programming interface (API), which is used for intensive I/O operations. A key element in NIO is the buffer as an object that contains data. The data is sent/received from an I/O service via a channel, which represents a connection to the hardware device. Other features of NIO are the character set encoding and regular expressions. NIO.2 brings an improved file system interface and asynchronous I/O.

The book is structured as an extended manual. The classes and methods are listed and defined in detail. I found many pertinent observations of the API usage. The flow of complicated operations is well explained. Numerous code examples cover more than half of the book. The type fonts are easy to read and follow the known convention. One problem is the lack of section numbering, which leads to some confusion.

Overall, this is a useful companion book for every Java programmer who needs to work with complex I/O operations.