FilterInputStream

The FilterInputStream is a base class for implementing your own filtering input streams. Basically it just overrides all methods in InputStream and passes all calls to any method on the FilterInputStream onto a wrapped InputStream. The wrapped InputStream is passed to the FilterInputStream in its constructor, like this:

FilterInputStream inputStream = new FilterInputStream(new FileInputStream("c:\\myfile.txt"));

The FilterInputStream class does not have any special behaviour. It is intended to be a base class for your own subclasses, but in my opinion you might as well just subclass InputStream directly.

Personally, I see no sensible purpose for this class. I cannot see that this class actually adds or changes any behaviour in InputStream except that it takes an InputStream in its constructor.