org.mozilla.universalchardet

Class UnicodeBOMInputStream

java.lang.Object

java.io.InputStream

org.mozilla.universalchardet.UnicodeBOMInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class UnicodeBOMInputStream
extends InputStream

The UnicodeBOMInputStream class wraps any InputStream and detects the presence of any Unicode BOM (Byte Order Mark) at its beginning, as defined by RFC 3629 - UTF-8, a transformation format of ISO 10646

The Unicode FAQ defines 5 types of BOMs:

• 00 00 FE FF  = UTF-32, big-endian

• FF FE 00 00  = UTF-32, little-endian

• FE FF        = UTF-16, big-endian

• FF FE        = UTF-16, little-endian

• EF BB BF     = UTF-8

Use the getBOM() method to know whether a BOM has been detected or not.

Use the skipBOM() method to remove the detected BOM from the wrapped InputStream object.

Version:

1.0

Author:

Gregory Pakosz

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	UnicodeBOMInputStream.BOM Type safe enumeration class that describes the different types of Unicode BOMs.

Constructor Summary

Constructors

Constructor and Description
UnicodeBOMInputStream(InputStream inputStream) Constructs a new UnicodeBOMInputStream that wraps the specified InputStream.
UnicodeBOMInputStream(InputStream inputStream, boolean skipIfFound) Constructs a new UnicodeBOMInputStream that wraps the specified InputStream.

Method Summary

Modifier and Type	Method and Description
int	available()
void	close()
UnicodeBOMInputStream.BOM	getBOM() Returns the BOM that was detected in the wrapped InputStream object.
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)
UnicodeBOMInputStream	skipBOM() Skips the BOM that was found in the wrapped InputStream object.

Methods inherited from class java.lang.Object

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

Constructor Detail

UnicodeBOMInputStream

public UnicodeBOMInputStream(InputStream inputStream)
                      throws IOException

Constructs a new UnicodeBOMInputStream that wraps the specified InputStream. By default skip BOM bytes

Parameters:

inputStream - an InputStream.

Throws:

NullPointerException - when inputStream is null.

IOException - on reading from the specified InputStream when trying to detect the Unicode BOM.

UnicodeBOMInputStream

public UnicodeBOMInputStream(InputStream inputStream,
                             boolean skipIfFound)
                      throws IOException

Constructs a new UnicodeBOMInputStream that wraps the specified InputStream.

Parameters:

inputStream - an InputStream.

skipIfFound - to automatically skip BOM bytes if found

Throws:

NullPointerException - when inputStream is null.

IOException - on reading from the specified InputStream when trying to detect the Unicode BOM.

Method Detail

getBOM

public final UnicodeBOMInputStream.BOM getBOM()

Returns the BOM that was detected in the wrapped InputStream object.

Returns:

a BOM value.

skipBOM

public final UnicodeBOMInputStream skipBOM()
                                    throws IOException

Skips the BOM that was found in the wrapped InputStream object.

Returns:

this UnicodeBOMInputStream.

Throws:

IOException - when trying to skip the BOM from the wrapped InputStream object.

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

skip

public long skip(long n)
          throws IOException

Overrides:

skip in class InputStream

Throws:

IOException

available

public int available()
              throws IOException

Overrides:

available in class InputStream

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class InputStream

Throws:

IOException

mark

public void mark(int readlimit)

Overrides:

mark in class InputStream

reset

public void reset()
           throws IOException

Overrides:

reset in class InputStream

Throws:

IOException

markSupported

public boolean markSupported()

Overrides:

markSupported in class InputStream