edu.vt.middleware.crypt.io
Class AbstractEncodingFilterInputStream

java.lang.Object
  java.io.InputStream
      java.io.FilterInputStream
          edu.vt.middleware.crypt.io.AbstractEncodingFilterInputStream

All Implemented Interfaces:

Closeable

Direct Known Subclasses:

Base64FilterInputStream, HexFilterInputStream

public abstract class AbstractEncodingFilterInputStream
extends FilterInputStream

Abstract base class for filter input streams that decode encoded character bytes into raw bytes.

Version:

$Revision: 3 $

Author:

Middleware Services

Field Summary

protected byte[]	byteBuffer Holds bytes encoded bytes read from input stream.
protected static int	CHUNK_SIZE Number of encoded bytes to read in one buffer filling round.
protected DirectByteArrayOutputStream	decodeBuffer Buffer containing decoded bytes.
protected int	position Position in decoded byte buffer.

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

protected

AbstractEncodingFilterInputStream(InputStream in) Creates an input filter that decodes characters in the given input stream.

Method Summary

protected abstract void	fillBuffer() Reads characters from the input reader and decodes them to fill decodeBuffer.
protected abstract int	getDecodeBufferCapacity() Gets the encoder that decodes encoded character data in the input stream to raw bytes.
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)

Methods inherited from class java.io.FilterInputStream

available, close, mark, markSupported, reset, skip

Methods inherited from class java.lang.Object

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

Field Detail

CHUNK_SIZE

protected static final int CHUNK_SIZE

Number of encoded bytes to read in one buffer filling round.

See Also:

Constant Field Values

decodeBuffer

protected final DirectByteArrayOutputStream decodeBuffer

Buffer containing decoded bytes.

byteBuffer

protected final byte[] byteBuffer

Holds bytes encoded bytes read from input stream.

position

protected int position

Position in decoded byte buffer.

Constructor Detail

AbstractEncodingFilterInputStream

protected AbstractEncodingFilterInputStream(InputStream in)

Creates an input filter that decodes characters in the given input stream.

Parameters:

in - Input stream to wrap.

Method Detail

read

public int read()
         throws IOException

Overrides:

read in class FilterInputStream

Throws:

IOException

read

public int read(byte[] b)
         throws IOException

Overrides:

read in class FilterInputStream

Throws:

IOException

read

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

Overrides:

read in class FilterInputStream

Throws:

IOException

getDecodeBufferCapacity

protected abstract int getDecodeBufferCapacity()

Gets the encoder that decodes encoded character data in the input stream to raw bytes.

Returns:

Encoder instance.

fillBuffer

protected abstract void fillBuffer()
                            throws IOException

Reads characters from the input reader and decodes them to fill decodeBuffer.

Throws:

IOException - On read errors.