Package org.dellroad.stuff.io

Class BOMReader

java.lang.Object

java.io.Reader

org.dellroad.stuff.io.BOMReader

All Implemented Interfaces:

Closeable, AutoCloseable, Readable

public class BOMReader
extends Reader

A Reader that wraps an InputStream, detects and strips the byte order mark, and then converts bytes into characters accordingly.

If no byte order mark is found, the input is implicitly assumed to be in some default character encoding.

The default character encoding and the action to take on malformed input are configurable.

See Also:

• Byte order mark

Field Summary

Fields inherited from class java.io.Reader

lock

Constructor Summary

Constructors

Constructor	Description
BOMReader(InputStream input)	Constructor.
BOMReader(InputStream input, CodingErrorAction errorAction, Charset defaultCharset)	Primary constructor.

Method Summary

Modifier and Type	Method	Description
void	close()
BOM	getBOM()	Get the BOM found at the beginning of the input.
Charset	getCharset()	Get the actual character encoding used.
void	mark(int limit)
int	read()
int	read(char[] cbuf)
int	read(char[] cbuf, int off, int len)
int	read(CharBuffer target)
boolean	ready()
void	reset()
long	skip(long num)

Methods inherited from class java.io.Reader

markSupported, nullReader, transferTo

Methods inherited from class java.lang.Object

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

Constructor Details

BOMReader

public BOMReader(InputStream input)

Constructor.

Equivalent to BOMReader(input, CodingErrorAction.REPORT, Charset.defaultCharset()).

Parameters:

input - data input

Throws:

IllegalArgumentException - if input is null

BOMReader

public BOMReader(InputStream input,
 CodingErrorAction errorAction,
 Charset defaultCharset)

Primary constructor.

The errorAction configures the behavior when malformed input is encountered; in the case of CodingErrorAction.REPORT, a MalformedInputException exception is thrown.

Parameters:

input - data input

errorAction - what to do about malformed input

defaultCharset - character encoding to use if no BOM is found

Throws:

IllegalArgumentException - if any parameter is null

Method Details

getBOM

public BOM getBOM()
           throws IOException

Get the BOM found at the beginning of the input.

If no input has been read yet, this method will trigger the reading of the first few bytes.

Returns:

the BOM that was detected, or null if no supported BOM was found

Throws:

IOException

getCharset

public Charset getCharset()
                   throws IOException

Get the actual character encoding used.

If no input has been read yet, this method will trigger the reading of the first few bytes.

Returns:

the character encoding chosen to decode the data, never null

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Specified by:

close in class Reader

Throws:

IOException

mark

public void mark(int limit)
          throws IOException

Overrides:

mark in class Reader

Throws:

IOException

read

public int read()
         throws IOException

Overrides:

read in class Reader

Throws:

IOException

read

public int read(char[] cbuf)
         throws IOException

Overrides:

read in class Reader

Throws:

IOException

read

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

Specified by:

read in class Reader

Throws:

IOException

read

public int read(CharBuffer target)
         throws IOException

Specified by:

read in interface Readable

Overrides:

read in class Reader

Throws:

IOException

ready

public boolean ready()
              throws IOException

Overrides:

ready in class Reader

Throws:

IOException

reset

public void reset()
           throws IOException

Overrides:

reset in class Reader

Throws:

IOException

skip

public long skip(long num)
          throws IOException

Overrides:

skip in class Reader

Throws:

IOException