com.mucommander.io
Class ThroughputLimitInputStream

java.lang.Object
  java.io.InputStream
      com.mucommander.io.ThroughputLimitInputStream

All Implemented Interfaces:

java.io.Closeable

public class ThroughputLimitInputStream
extends java.io.InputStream

ThroughputLimitInputStream extends InputStream to provide control over the transfer speed and limit it to a specified number of bytes per second. Whenever the bytes per second quota has been reached, the read and skip methods will lock and won't return until either:

a new second commences, bringing the bytes read count back to zero for the new second
• setThroughputLimit(long) is called with a more permissive bytes per second value (different from 0), yielding to more bytes available for the current second.

  Setting the throughput limit to 0 effectively blocks all read and skip calls indefinitely. Any calls to the read or skip methods will lock, the only way to remove this lock being to call the setThroughputLimit(long) method with a value different from 0 from another thread.

  Setting the throughput limit to -1 or any other negative values will disable any limit and make this ThroughputLimitInputStream behave just like a normal InputStream.

  Finally, the setUnderlyingInputStream(java.io.InputStream) method allows to use the same ThroughputLimitInputStream instance for multiple InputStream instances, keeping the bytes count for the current second intact and thus the throughput limit stable. This does not hold true if a new ThroughputLimitInputStream is created for each InputStream, the bytes count for the current second starting at 0.

  Author:

  Maxence Bernard

  Constructor Summary

  ThroughputLimitInputStream(java.io.InputStream in)
  Creates a new ThroughputLimitInputStream with no initial throughput limit (-1 value).

  ThroughputLimitInputStream(java.io.InputStream in, long bytesPerSecond)
  Creates a new ThroughputLimitInputStream with an initial throughput limit.

  Method Summary

  int	available()
  void	close()
  void	mark(int i)
  boolean	markSupported()
  int	read()
  int	read(byte[] bytes)
  int	read(byte[] bytes, int off, int len)
  void	reset()
  void	setThroughputLimit(long bytesPerSecond) Specifies a new throughput limit expressed in bytes per second.
  void	setUnderlyingInputStream(java.io.InputStream in) Changes the underlying InputStream which data is read from, keeping the bytes count for the current second intact.
  long	skip(long l)

  Methods inherited from class java.lang.Object

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

  Constructor Detail

  ThroughputLimitInputStream

  public ThroughputLimitInputStream(java.io.InputStream in)

  Creates a new ThroughputLimitInputStream with no initial throughput limit (-1 value).

  Parameters:

  in - underlying stream that is used to read data from

  ThroughputLimitInputStream

  public ThroughputLimitInputStream(java.io.InputStream in,
                                    long bytesPerSecond)

  Creates a new ThroughputLimitInputStream with an initial throughput limit.

  Parameters:

  in - underlying stream that is used to read data from

  bytesPerSecond - initial throughput limit in bytes per second

  See Also:

  setThroughputLimit(long)

  Method Detail

  setThroughputLimit

  public void setThroughputLimit(long bytesPerSecond)

  Specifies a new throughput limit expressed in bytes per second. The new limit will take effect the next time one of the read or skip methods are called.

  Setting the throughput limit to 0 effectively blocks all read and skip calls indefinitely. Any calls to the read or skip methods will lock, the only way to remove this lock being to call the setThroughputLimit(long) method with a value different from 0 from another thread.

  Setting the throughput limit to -1 or any other negative values will disable any limit and make this ThroughputLimitInputStream behave just like a normal InputStream.

  Parameters:

  bytesPerSecond - new throughput limit expressed in bytes, -1 to disable it, 0 to block reads.

  setUnderlyingInputStream

  public void setUnderlyingInputStream(java.io.InputStream in)

  Changes the underlying InputStream which data is read from, keeping the bytes count for the current second intact.

  Note: the existing underlying InputStream will not be closed, the close() method must be called prior to calling this method.

  Parameters:

  in - the new InputStream to read data from

  read

  public int read()
           throws java.io.IOException

  Specified by:

  read in class java.io.InputStream

  Throws:

  java.io.IOException

  read

  public int read(byte[] bytes)
           throws java.io.IOException

  Overrides:

  read in class java.io.InputStream

  Throws:

  java.io.IOException

  read

  public int read(byte[] bytes,
                  int off,
                  int len)
           throws java.io.IOException

  Overrides:

  read in class java.io.InputStream

  Throws:

  java.io.IOException

  skip

  public long skip(long l)
            throws java.io.IOException

  Overrides:

  skip in class java.io.InputStream

  Throws:

  java.io.IOException

  available

  public int available()
                throws java.io.IOException

  Overrides:

  available in class java.io.InputStream

  Throws:

  java.io.IOException

  close

  public void close()
             throws java.io.IOException

  Specified by:

  close in interface java.io.Closeable

  Overrides:

  close in class java.io.InputStream

  Throws:

  java.io.IOException

  mark

  public void mark(int i)

  Overrides:

  mark in class java.io.InputStream

  reset

  public void reset()
             throws java.io.IOException

  Overrides:

  reset in class java.io.InputStream

  Throws:

  java.io.IOException

  markSupported

  public boolean markSupported()

  Overrides:

  markSupported in class java.io.InputStream