When you use memory mapping, you make a single buffer that spans the entire file or the area of the file that you’re interested in. You can also use buffers to read and write more modest chunks of information.
In this section, we briefly describe the basic operations on
Buffer objects. A buffer is an array of values of the same type. The
Buffer class is an abstract class with concrete subclasses
StringBuffer class is not related to these buffers.
In practice, you will most commonly use