org.htmlparser.lexer
Class Stream

java.lang.Object
  java.io.InputStream
      org.htmlparser.lexer.Stream

All Implemented Interfaces:

java.lang.Runnable

public class Stream

extends java.io.InputStream

implements java.lang.Runnable

Provides for asynchronous fetching from a stream.

Field Summary

protected static int	BUFFER_SIZE An initial buffer size.
protected static int	EOF Return value when no more characters are left.
int	fills The number of calls to fill.
byte[]	mBuffer The bytes read so far.
protected int	mContentLength The content length from the HTTP header.
protected java.io.InputStream	mIn The underlying stream.
int	mLevel The number of valid bytes in the buffer.
protected int	mMark The bookmark.
protected int	mOffset The offset of the next byte returned by read().
int	reallocations The number of reallocations.
int	synchronous The number of synchronous (blocking) fills.

Constructor Summary

Stream(java.io.InputStream in)
Construct a stream with no assumptions about the number of bytes available.

Stream(java.io.InputStream in, int bytes)
Construct a stream to read the given number of bytes.

Method Summary

int	available() Returns the number of bytes that can be read (or skipped over) from this input stream without blocking by the next caller of a method for this input stream.
void	close() Closes this input stream and releases any system resources associated with the stream.
protected boolean	fill(boolean force) Fetch more bytes from the underlying stream.
void	mark(int readlimit) Marks the current position in this input stream.
boolean	markSupported() Tests if this input stream supports the mark and reset methods.
int	read() Reads the next byte of data from the input stream.
void	reset() Repositions this stream to the position at the time the mark method was last called on this input stream.
void	run() Continually read the underlying stream untill exhausted.

Methods inherited from class java.io.InputStream

read, read, skip

Methods inherited from class java.lang.Object

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

Field Detail

fills

public int fills

The number of calls to fill. Note: to be removed.

reallocations

public int reallocations

The number of reallocations. Note: to be removed.

synchronous

public int synchronous

The number of synchronous (blocking) fills. Note: to be removed.

BUFFER_SIZE

protected static final int BUFFER_SIZE

An initial buffer size.

See Also:

Constant Field Values

EOF

protected static final int EOF

Return value when no more characters are left.

See Also:

Constant Field Values

mIn

protected volatile java.io.InputStream mIn

The underlying stream.

mBuffer

public volatile byte[] mBuffer

The bytes read so far.

mLevel

public volatile int mLevel

The number of valid bytes in the buffer.

mOffset

protected int mOffset

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

mContentLength

protected int mContentLength

The content length from the HTTP header.

mMark

protected int mMark

The bookmark.

Constructor Detail

Stream

public Stream(java.io.InputStream in)

Construct a stream with no assumptions about the number of bytes available.

Parameters:

in - The input stream to use.

Stream

public Stream(java.io.InputStream in,
              int bytes)

Construct a stream to read the given number of bytes.

Parameters:

in - The input stream to use.

bytes - The maximum number of bytes to read. This should be set to the ContentLength from the HTTP header. A negative or zero value indicates an unknown number of bytes.

Method Detail

fill

protected boolean fill(boolean force)
                throws java.io.IOException

Fetch more bytes from the underlying stream. Has no effect if the underlying stream has been drained.

Parameters:

force - If true, an attempt is made to read from the underlying stream, even if bytes are available, If false, a read of the underlying stream will not occur if there are already bytes available.

Returns:

true if not at the end of the input stream.

Throws:

java.io.IOException - If the underlying stream read() or available() throws one.

run

public void run()

Continually read the underlying stream untill exhausted.

Specified by:

run in interface java.lang.Runnable

See Also:

Thread.run()

read

public int read()
         throws java.io.IOException

Reads the next byte of data from the input stream. The value byte is returned as an int in the range 0 to 255. If no byte is available because the end of the stream has been reached, the value -1 is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

Returns:

The next byte of data, or -1 if the end of the stream is reached.

Throws:

java.io.IOException - If an I/O error occurs.

available

public int available()
              throws java.io.IOException

Returns the number of bytes that can be read (or skipped over) from this input stream without blocking by the next caller of a method for this input stream. The next caller might be the same thread or or another thread.

Returns:

The number of bytes that can be read from this input stream without blocking.

Throws:

java.io.IOException - If an I/O error occurs.

close

public void close()
           throws java.io.IOException

Closes this input stream and releases any system resources associated with the stream.

Throws:

java.io.IOException - If an I/O error occurs.

reset

public void reset()
           throws java.io.IOException

Repositions this stream to the position at the time the mark method was last called on this input stream.

The general contract of reset is:

• If the method markSupported returns true, then:
  • If the method mark has not been called since the stream was created, or the number of bytes read from the stream since mark was last called is larger than the argument to mark at that last call, then an IOException might be thrown.
  • If such an IOException is not thrown, then the stream is reset to a state such that all the bytes read since the most recent call to mark (or since the start of the file, if mark has not been called) will be resupplied to subsequent callers of the read method, followed by any bytes that otherwise would have been the next input data as of the time of the call to reset.
• If the method markSupported returns false, then:
  • The call to reset may throw an IOException.
  • If an IOException is not thrown, then the stream is reset to a fixed state that depends on the particular type of the input stream and how it was created. The bytes that will be supplied to subsequent callers of the read method depend on the particular type of the input stream.

Throws:

java.io.IOException - Never thrown. Just for subclassers.

See Also:

InputStream.mark(int), IOException

markSupported

public boolean markSupported()

Tests if this input stream supports the mark and reset methods. Whether or not mark and reset are supported is an invariant property of a particular input stream instance. The markSupported method of InputStream returns false.

Returns:

true.

See Also:

InputStream.mark(int), InputStream.reset()

mark

public void mark(int readlimit)

Marks the current position in this input stream. A subsequent call to the reset method repositions this stream at the last marked position so that subsequent reads re-read the same bytes.

The readlimit arguments tells this input stream to allow that many bytes to be read before the mark position gets invalidated.

The general contract of mark is that, if the method markSupported returns true, the stream somehow remembers all the bytes read after the call to mark and stands ready to supply those same bytes again if and whenever the method reset is called. However, the stream is not required to remember any data at all if more than readlimit bytes are read from the stream before reset is called.

Parameters:

readlimit - Not used.

See Also:

InputStream.reset()