net.sf.zig_project.gpl.simulation
Class SlowInputStream

java.lang.Object
  java.io.InputStream
      java.io.FilterInputStream
          net.sf.zig_project.gpl.simulation.SlowInputStream

public class SlowInputStream

extends FilterInputStream

The SlowInputStream class slows down a given InputStream. This prevents the given InputStream from returning as soon as it is completed. Hence, the behavior of this stream is to operate as slowly (or possibly slower) than the specified data rate.

This class is used within the Simulation package, and hence is designed for configuring simulated test environments, not for precision timing.

Version:

September 24, 2004

Author:

Frank Ziglar

Field Summary

protected double

nSpB delay time, measured in Nanoseconds per Byte

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

SlowInputStream(InputStream is, double BpS)
Creates a SlowInputStream layer.

Method Summary

int	read() Reads a single byte of data from the underlying InputStream.
int	read(byte[] buf, int off, int len) Reads data into the buffer from the underlying InputStream.

Methods inherited from class java.io.FilterInputStream

available, close, mark, markSupported, read, reset, skip

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

nSpB

protected final double nSpB

delay time, measured in Nanoseconds per Byte

Constructor Detail

SlowInputStream

public SlowInputStream(InputStream is,
                       double BpS)

Creates a SlowInputStream layer.

Parameters:

is - the InputStream to load data from

BpS - the data rate to emulate, in Bytes / sec

Method Detail

read

public int read()
         throws IOException

Reads a single byte of data from the underlying InputStream. This method will pause at the rate of 1 / the constructed paramater BpS until the end of the stream is reached. It is however, recommended that this stream be buffered, instead of calling this method directly, in order for timing to be conducted more accurately.

Throws:

IOException

read

public int read(byte[] buf,
                int off,
                int len)
         throws IOException

Reads data into the buffer from the underlying InputStream. This method will pause based on the amount of data actually loaded to emulate the fixed data rate. If the stream has been ended, this method will return immediately.

Throws:

IOException