com.gc.iotools.stream.is
Class SizeLimitInputStream

java.lang.Object
  java.io.InputStream
      com.gc.iotools.stream.is.SizeLimitInputStream

All Implemented Interfaces:

Closeable

public class SizeLimitInputStream
extends InputStream

An input stream wrapper that will read only a definite number of bytes from the underlying stream.

Since:

1.2.0

Author:

dvd.smnt

Field Summary

protected long	currentPosition The number of bytes that have been read from the in stream.
protected InputStream	in The underlying stream from which data are read.
protected long	markPosition The position in the stream when mark(int) was called.
protected long	maxSize The number of bytes to read at most from the in stream.

Constructor Summary

SizeLimitInputStream(InputStream in, long maxSize)
Create a new SizeLimitInputStream from another stream given a size limit.

Method Summary

int	available()
void	close() Close the underlying stream.
long	getBytesLeft() Get the maximum number of bytes left to read before the limit, set in the constructor, is reached.
long	getBytesRead() Get the number of bytes actually read from this stream.
long	getMaxSize() Get the number of total bytes (including bytes already read) that can be read from this stream (as set in the constructor).
void	mark(int readlimit)
boolean	markSupported()
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)
void	reset()
long	skip(long n)

Methods inherited from class java.lang.Object

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

Field Detail

in

protected InputStream in

The underlying stream from which data are read. All methods are forwarded to it, after checking that the maxSize size that hasn't been reached.

maxSize

protected final long maxSize

The number of bytes to read at most from the in stream. Read methods should check to ensure that the number of bytes read never exceeds maxSize.

currentPosition

protected long currentPosition

The number of bytes that have been read from the in stream. Read methods should check to ensure that currentPosition never exceeds maxSize.

markPosition

protected long markPosition

The position in the stream when mark(int) was called. It's used to reset the current position when reset() is called.

Constructor Detail

SizeLimitInputStream

public SizeLimitInputStream(InputStream in,
                            long maxSize)

Create a new SizeLimitInputStream from another stream given a size limit.

Bytes are read from the underlying stream until size limit is reached.

Parameters:

in - The underlying input stream from where the data is read.

maxSize - the max number of bytes to allow to be read from the underlying stream.

Method Detail

available

public int available()
              throws IOException

Overrides:

available in class InputStream

Throws:

IOException

close

public void close()
           throws IOException

Close the underlying stream. Calling this method may make data on the underlying stream unavailable.

Specified by:

close in interface Closeable

Overrides:

close in class InputStream

Throws:

IOException - Exception is thrown when some IO error happens in the underlying stream.

getBytesLeft

public long getBytesLeft()

Get the maximum number of bytes left to read before the limit, set in the constructor, is reached.

Returns:

The number of bytes that (at a maximum) are left to be taken from this stream.

getBytesRead

public long getBytesRead()

Get the number of bytes actually read from this stream.

Returns:

number of bytes that have already been taken from this stream.

getMaxSize

public long getMaxSize()

Get the number of total bytes (including bytes already read) that can be read from this stream (as set in the constructor).

Returns:

Maximum bytes that can be read until the size limit runs out

mark

public void mark(int readlimit)

Overrides:

mark in class InputStream

markSupported

public boolean markSupported()

Overrides:

markSupported in class InputStream

read

public int read()
         throws IOException

Specified by:

read in class InputStream

Throws:

IOException

read

public int read(byte[] b)
         throws IOException

Overrides:

read in class InputStream

Throws:

IOException

read

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

Overrides:

read in class InputStream

Throws:

IOException

reset

public void reset()
           throws IOException

Overrides:

reset in class InputStream

Throws:

IOException

skip

public long skip(long n)
          throws IOException

Overrides:

skip in class InputStream

Throws:

IOException