org.wandora.utils

Class UnicodeBOMInputStream

java.lang.Object

java.io.InputStream

org.wandora.utils.UnicodeBOMInputStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class UnicodeBOMInputStream
extends java.io.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.

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.

Field Summary

Fields

Modifier and Type	Field and Description
private UnicodeBOMInputStream.BOM	bom
private java.io.PushbackInputStream	in
private boolean	skipped

Constructor Summary

Constructors

Constructor and Description
UnicodeBOMInputStream(java.io.InputStream inputStream) 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

Field Detail

in

private final java.io.PushbackInputStream in

bom

private final UnicodeBOMInputStream.BOM bom

skipped

private boolean skipped

Constructor Detail

UnicodeBOMInputStream

public UnicodeBOMInputStream(java.io.InputStream inputStream)
                      throws java.lang.NullPointerException,
                             java.io.IOException

Constructs a new UnicodeBOMInputStream that wraps the specified InputStream.

Parameters:

inputStream - an InputStream.

Throws:

java.lang.NullPointerException - when inputStream is null.

java.io.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 java.io.IOException

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

Returns:

this UnicodeBOMInputStream.

Throws:

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

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,
                java.lang.NullPointerException

Overrides:

read in class java.io.InputStream

Throws:

java.io.IOException

java.lang.NullPointerException

read

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

Overrides:

read in class java.io.InputStream

Throws:

java.io.IOException

java.lang.NullPointerException

skip

public long skip(long n)
          throws java.io.IOException

Overrides:

skip in class java.io.InputStream

Throws:

java.io.IOException

available

public int available()
              throws java.io.IOException

Overrides:

available 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

Specified by:

close in interface java.lang.AutoCloseable

Overrides:

close in class java.io.InputStream

Throws:

java.io.IOException

mark

public void mark(int readlimit)

Overrides:

mark in class java.io.InputStream

reset

public void reset()
           throws java.io.IOException

Overrides:

reset in class java.io.InputStream

Throws:

java.io.IOException

markSupported

public boolean markSupported()

Overrides:

markSupported in class java.io.InputStream