it.unimi.dsi.fastutil.io

Interface MeasurableStream

All Known Implementing Classes:

FastBufferedInputStream, FastBufferedOutputStream, FastByteArrayInputStream, FastByteArrayOutputStream, FastMultiByteArrayInputStream, InspectableFileCachedInputStream, MeasurableInputStream, MeasurableOutputStream

public interface MeasurableStream

An stream that provides eager access to its length, and keeps track of the current position (e.g., the number of bytes read so far, or the current position of the file pointer).

This class has two methods, both specified as optional. This apparently bizarre behaviour is necessary because of wrapper classes which use reflection to support those methods (see, e.g., MeasurableInputStream, FastBufferedInputStream and FastBufferedOutputStream).

Since:

6.0.0

Method Summary

Methods

Modifier and Type	Method and Description
long	length() Returns the overall length of this stream (optional operation).
long	position() Returns the current position in this stream (optional operation).

Method Detail

length

long length()
            throws IOException

Returns the overall length of this stream (optional operation). In most cases, this will require the stream to perform some extra action, possibly changing the state of the input stream itself (typically, reading all the bytes up to the end, or flushing on output stream). Implementing classes should always document what state will the input stream be in after calling this method, and which kind of exception could be thrown.

Throws:

IOException

position

long position()
              throws IOException

Returns the current position in this stream (optional operation).

Usually, the position is just the number of bytes read or written since the stream was opened, but in the case of a RepositionableStream it represent the current position.

Throws:

IOException