Learning Java, 7th Edition

Chapter 9. File Input and Output

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The ability to store data in files and retrieve it later is crucial to desktop and enterprise applications. In this chapter, we’ll look at some of the most popular classes in the java.io and java.nio packages. These packages offer a rich set of tools for basic input and output (I/O) and also provide the framework on which all file and network communication in Java are built. Figure 9-1 shows the breadth of the java.io package.

We’ll start by looking at the stream classes in java.io, which are subclasses of the basic InputStream, OutputStream, Reader, and Writer classes. Then we’ll examine the File class and discuss how you can read and write files using classes in java.io. We also take a quick look at data compression and serialization. Along the way, we introduce the java.nio package. The “new” I/O package (or NIO) adds significant functionality tailored for building high-performance services. NIO centers on working with buffers (where you store stuff to make ...