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

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

    • length

      long length() throws java.io.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:
      java.io.IOException
    • position

      long position() throws java.io.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:
      java.io.IOException