Here is a description of class "Class Buffer" in Java.
Buffer is abstract class and it extends the Object class.
public abstract class Buffer extends Object;
*A buffer is a linear, finite sequence of elements of a specific primitive type. Aside from its content, the essential properties of a buffer are its capacity, limit, and position:
*A buffer's capacity is the number of elements it contains. The capacity of a buffer is never negative and never changes.
*A buffer's limit is the index of the first element that should not be read or written. A buffer's limit is never negative and is never greater than the its capacity.
*A buffer's position is the index of the next element to be read or written. A buffer's position is never negative and is never greater than its limit.
In case of buffer class nothing is created as physical object.
Here is an example of StringBuffer class in Java:http://www.roseindia.net/java/beginners/StringBuffer.shtml