com.bea.xml.stream.reader

Class XmlReader


public final class XmlReader
extends Reader

This handles several XML-related tasks that normal java.io Readers don't support, inluding use of IETF standard encoding names and automatic detection of most XML encodings. The former is needed for interoperability; the latter is needed to conform with the XML spec. This class also optimizes reading some common encodings by providing low-overhead unsynchronized Reader support.

Note that the autodetection facility should be used only on data streams which have an unknown character encoding. For example, it should never be used on MIME text/xml entities.

Note that XML processors are only required to support UTF-8 and UTF-16 character encodings. Autodetection permits the underlying Java implementation to provide support for many other encodings, such as US-ASCII, ISO-8859-5, Shift_JIS, EUC-JP, and ISO-2022-JP.

Version:
$Revision: 1.1 $
Author:
David Brownell

Nested Class Summary

static class
XmlReader.BaseReader

Method Summary

void
close()
Closes the reader.
static Reader
createReader(InputStream in)
Constructs the reader from an input stream, autodetecting the encoding to use according to the heuristic specified in the XML 1.0 recommendation.
static Reader
createReader(InputStream in, String encoding)
Creates a reader supporting the given encoding, mapping from standard encoding names to ones that understood by Java where necessary.
String
getEncoding()
Returns the standard name of the encoding in use
void
mark(int value)
Sets a mark allowing a limited number of characters to be "peeked", by reading and then resetting.
boolean
markSupported()
Returns true iff the reader supports mark/reset.
int
read()
Reads a single character.
int
read(buf[] , int off, int len)
Reads the number of characters read into the buffer, or -1 on EOF.
boolean
ready()
Returns true iff input characters are known to be ready.
void
reset()
Resets the current position to the last marked position.
long
skip(long value)
Skips a specified number of characters.

Method Details

close

public void close()
            throws IOException
Closes the reader.

createReader

public static Reader createReader(InputStream in)
            throws IOException
Constructs the reader from an input stream, autodetecting the encoding to use according to the heuristic specified in the XML 1.0 recommendation.
Parameters:
in - the input stream from which the reader is constructed

createReader

public static Reader createReader(InputStream in,
                                  String encoding)
            throws IOException
Creates a reader supporting the given encoding, mapping from standard encoding names to ones that understood by Java where necessary.
Parameters:
in - the input stream from which the reader is constructed
encoding - the IETF standard name of the encoding to use; if null, autodetection is used.

getEncoding

public String getEncoding()
Returns the standard name of the encoding in use

mark

public void mark(int value)
            throws IOException
Sets a mark allowing a limited number of characters to be "peeked", by reading and then resetting.
Parameters:
value - how many characters may be "peeked".

markSupported

public boolean markSupported()
Returns true iff the reader supports mark/reset.

read

public int read()
            throws IOException
Reads a single character.

read

public int read(buf[] ,
                int off,
                int len)
            throws IOException
Reads the number of characters read into the buffer, or -1 on EOF.

ready

public boolean ready()
            throws IOException
Returns true iff input characters are known to be ready.

reset

public void reset()
            throws IOException
Resets the current position to the last marked position.

skip

public long skip(long value)
            throws IOException
Skips a specified number of characters.