org.htmlparser.lexer
Class Source

java.lang.Object
  java.io.Reader
      org.htmlparser.lexer.Source

All Implemented Interfaces:

Serializable

public class Source

extends Reader

implements Serializable

A buffered source of characters. A Source is very similar to a the following construct:

 new InputStreamReader (new BufferedInputStream (connection.getInputStream ()), charset)
 

It differs from the above, in two ways:

the fetching of bytes from the connection's input stream may be asynchronous

the character set may be changed, which resets the input stream

See Also:

Serialized Form

Field Summary

static int	BUFFER_SIZE An initial buffer size.
static int	EOF Return value when no more characters are left.
char[]	mBuffer The characters read so far.
protected String	mEncoding The character set in use.
int	mLevel The number of valid bytes in the buffer.
protected int	mMark The bookmark.
int	mOffset The offset of the next byte returned by read().
protected InputStreamReader	mReader The converter from bytes to characters.
protected InputStream	mStream The stream of bytes.

Fields inherited from class java.io.Reader

lock

Constructor Summary

Source(InputStream stream)
Create a source of characters using the default character set.

Source(InputStream stream, String charset)
Create a source of characters.

Source(InputStream stream, String charset, int buffer_size)
Create a source of characters.

Method Summary

int	available() Get the number of available characters.
void	close() Does nothing.
void	destroy() Close the stream.
protected void	fill(int min) Fetch more characters from the underlying reader.
String	getEncoding() Get the encoding being used to convert characters.
InputStream	getStream() Get the input stream being used.
void	mark(int readAheadLimit) Mark the present position in the stream.
boolean	markSupported() Tell whether this stream supports the mark() operation.
int	offset() Get the position (in characters).
int	read() Read a single character.
int	read(char[] cbuf) Read characters into an array.
int	read(char[] cbuf, int off, int len) Read characters into a portion of an array.
boolean	ready() Tell whether this stream is ready to be read.
void	reset() Reset the source.
long	skip(long n) Skip characters.
void	unread() Undo the read of a single character.

Methods inherited from class java.lang.Object

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

Field Detail

BUFFER_SIZE

public static int BUFFER_SIZE

An initial buffer size.

EOF

public static final int EOF

Return value when no more characters are left.

See Also:

Constant Field Values

mStream

protected transient InputStream mStream

The stream of bytes.

mEncoding

protected String mEncoding

The character set in use.

mReader

protected transient InputStreamReader mReader

The converter from bytes to characters.

mBuffer

public char[] mBuffer

The characters read so far.

mLevel

public int mLevel

The number of valid bytes in the buffer.

mOffset

public int mOffset

The offset of the next byte returned by read().

mMark

protected int mMark

The bookmark.

Constructor Detail

Source

public Source(InputStream stream)
       throws UnsupportedEncodingException

Create a source of characters using the default character set.

Parameters:

stream - The stream of bytes to use.

Source

public Source(InputStream stream,
              String charset)
       throws UnsupportedEncodingException

Create a source of characters.

Parameters:

stream - The stream of bytes to use.

charset - The character set used in encoding the stream.

Source

public Source(InputStream stream,
              String charset,
              int buffer_size)
       throws UnsupportedEncodingException

Create a source of characters.

Parameters:

stream - The stream of bytes to use.

charset - The character set used in encoding the stream.

Method Detail

getStream

public InputStream getStream()

Get the input stream being used.

Returns:

The current input stream.

getEncoding

public String getEncoding()

Get the encoding being used to convert characters.

Returns:

The current encoding.

fill

protected void fill(int min)
             throws IOException

Fetch more characters from the underlying reader. Has no effect if the underlying reader has been drained.

Parameters:

min - The minimum to read.

Throws:

IOException - If the underlying reader read() throws one.

close

public void close()
           throws IOException

Does nothing. It's supposed to close the stream, but use destroy() instead.

Throws:

IOException

See Also:

destroy()

read

public int read()
         throws IOException

Read a single character. This method will block until a character is available, an I/O error occurs, or the end of the stream is reached.

Returns:

The character read, as an integer in the range 0 to 65535 (0x00-0xffff), or -1 if the end of the stream has been reached

Throws:

IOException - If an I/O error occurs.

read

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

Read characters into a portion of an array. This method will block until some input is available, an I/O error occurs, or the end of the stream is reached.

Parameters:

cbuf - Destination buffer

off - Offset at which to start storing characters

len - Maximum number of characters to read

Returns:

The number of characters read, or -1 if the end of the stream has been reached

Throws:

IOException - If an I/O error occurs.

read

public int read(char[] cbuf)
         throws IOException

Read characters into an array. This method will block until some input is available, an I/O error occurs, or the end of the stream is reached.

Parameters:

cbuf - Destination buffer.

Returns:

The number of characters read, or -1 if the end of the stream has been reached.

Throws:

IOException - If an I/O error occurs.

reset

public void reset()

Reset the source. Repositions the read point to begin at zero.

Throws:

IllegalStateException - If the source has been closed.

markSupported

public boolean markSupported()

Tell whether this stream supports the mark() operation.

Returns:

true if and only if this stream supports the mark operation.

mark

public void mark(int readAheadLimit)
          throws IOException

Mark the present position in the stream. Subsequent calls to reset() will attempt to reposition the stream to this point. Not all character-input streams support the mark() operation.

Parameters:

readAheadLimit - Not used.

Throws:

IOException - Never thrown.

ready

public boolean ready()
              throws IOException

Tell whether this stream is ready to be read.

Returns:

true if the next read() is guaranteed not to block for input, false otherwise. Note that returning false does not guarantee that the next read will block.

Throws:

IOException - Never thrown.

skip

public long skip(long n)
          throws IOException

Skip characters. This method will block until some characters are available, an I/O error occurs, or the end of the stream is reached. Note: n is treated as an int

Parameters:

n - The number of characters to skip.

Returns:

The number of characters actually skipped

Throws:

IllegalArgumentException - If n is negative.

IOException - If an I/O error occurs.

unread

public void unread()
            throws IOException

Undo the read of a single character.

Throws:

IOException - If no characters have been read.

destroy

public void destroy()
             throws IOException

Close the stream. Once a stream has been closed, further read(), ready(), mark(), or reset() invocations will throw an IOException. Closing a previously-closed stream, however, has no effect.

Throws:

IOException - If an I/O error occurs

offset

public int offset()

Get the position (in characters).

Returns:

The number of characters that have been read.

available

public int available()

Get the number of available characters.

Returns:

The number of characters that can be read without blocking.