com.gc.iotools.stream.writer

Class SizeLimitReader

java.lang.Object

java.io.Reader

com.gc.iotools.stream.writer.SizeLimitReader

All Implemented Interfaces:

Closeable, AutoCloseable, Readable

public class SizeLimitReader
extends Reader

A Reader wrapper that will read only a definite number of characters from the underlying stream.

Since:

1.2.15

Author:

G.Contini

Field Summary

Fields

Modifier and Type	Field and Description
protected long	currentPosition The number of characters that have been read from the in stream.
protected Reader	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 characters to read at most from the in stream.

Fields inherited from class java.io.Reader

lock

Constructor Summary

Constructors

Constructor and Description
SizeLimitReader(Reader in, long maxSize) Create a new SizeLimitInputStream from another stream given a size limit.

Method Summary

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

Methods inherited from class java.io.Reader

read, ready

Methods inherited from class java.lang.Object

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

Field Detail

currentPosition

protected long currentPosition

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

in

protected Reader 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.

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.

maxSize

protected final long maxSize

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

Constructor Detail

SizeLimitReader

public SizeLimitReader(Reader 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 characters to allow to be read from the underlying stream.

Method Detail

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

Specified by:

close in interface AutoCloseable

Specified by:

close in class Reader

Throws:

IOException

getBytesLeft

public long getBytesLeft()

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

Returns:

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

getBytesRead

public long getBytesRead()

Get the number of characters actually read from this stream.

Returns:

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

getMaxSize

public long getMaxSize()

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

Returns:

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

mark

public void mark(int readlimit)
          throws IOException

Overrides:

mark in class Reader

Throws:

IOException

markSupported

public boolean markSupported()

Overrides:

markSupported in class Reader

read

public int read()
         throws IOException

Overrides:

read in class Reader

Throws:

IOException

read

public int read(char[] b)
         throws IOException

Overrides:

read in class Reader

Throws:

IOException

read

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

Specified by:

read in class Reader

Throws:

IOException

reset

public void reset()
           throws IOException

Overrides:

reset in class Reader

Throws:

IOException

skip

public long skip(long n)
          throws IOException

Overrides:

skip in class Reader

Throws:

IOException