Learning Network Programming with Java

Introduction to buffers

Buffers hold data temporarily because it is being moved to and from channels. When a buffer is created, it is created with a fixed size or capacity. Part or all of a buffer's memory can be used with several Buffer class fields available to manage the data in a buffer.

The Buffer class is abstract. However, it possesses the basic methods used to manipulate a buffer, including:

• capacity: This returns the number of elements in the buffer
• limit: This returns the first index of the buffer that should not be accessed
• position: This returns the index of the next element to be read or written

The element depends on the buffer type.

The mark and reset methods also control the position within a buffer. The mark method will set the buffer's ...