com.mucommander.io.bom
Class BOMInputStream

java.lang.Object
  java.io.InputStream
      com.mucommander.io.bom.BOMInputStream

All Implemented Interfaces:

BOMConstants, java.io.Closeable

public class BOMInputStream
extends java.io.InputStream
implements BOMConstants

BOMInputStream is an InputStream which provides support for Byte-Order Marks (BOM). A BOM is a byte sequence found at the beginning of a Unicode text stream which indicates the encoding of the text that follows.

This class serves a dual purpose:
1) it allows to detect a BOM in the underlying stream and determine the encoding used by the stream: the BOM instance returned by getBOM() provides that information.
2) it allows to discard the BOM from a Unicode stream: the leading bytes corresponding to the BOM are swallowed by the stream and never returned by the read methods.

The following BOMs are supported by this class:

• UTF-8
• UTF-16 Big Endian
• UTF-16 Little Endian
• UTF-32 Big Endian.
• UTF-32 Little Endian

Note that UTF-32 encodings (both Little and Big Endians) are usually not supported by Java runtimes out of the box.

Author:

Maxence Bernard

See Also:

BOMReader

Field Summary

Fields inherited from interface com.mucommander.io.bom.BOMConstants

SUPPORTED_BOMS, UTF16_BE_BOM, UTF16_LE_BOM, UTF32_BE_BOM, UTF32_LE_BOM, UTF8_BOM

Constructor Summary

BOMInputStream(java.io.InputStream in)
Creates a new BOMInputStream and looks for a BOM at the beginning of the stream.

Method Summary

void	close()
BOM	getBOM() Returns the BOM that was found at the beginning of the stream if there was one, null otherwise.
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)

Methods inherited from class java.io.InputStream

available, mark, markSupported, reset, skip

Methods inherited from class java.lang.Object

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

Constructor Detail

BOMInputStream

public BOMInputStream(java.io.InputStream in)
               throws java.io.IOException

Creates a new BOMInputStream and looks for a BOM at the beginning of the stream.

Parameters:

in - the underlying stream

Throws:

java.io.IOException - if an error occurred while reading the given InputStream

Method Detail

getBOM

public BOM getBOM()

Returns the BOM that was found at the beginning of the stream if there was one, null otherwise.

Returns:

the BOM that was found at the beginning of the stream

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[] b)
         throws java.io.IOException

Overrides:

read in class java.io.InputStream

Throws:

java.io.IOException

read

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

Overrides:

read 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