gnu.java.net.protocol.core

Class CoreInputStream

Implemented Interfaces:
AutoCloseable, Closeable

public class CoreInputStream
extends InputStream

Field Summary

protected int
count
protected int
mark
protected int
pos
protected RawData
ptr

Constructor Summary

CoreInputStream(Core core)

Method Summary

int
available()
This method returns the number of bytes that can be read from this stream before a read can block.
void
mark(int readAheadLimit)
This method marks a position in the input to which the stream can be "reset" by calling the reset() method.
boolean
markSupported()
This method returns a boolean that indicates whether the mark/reset methods are supported in this class.
int
read()
This method reads an unsigned byte from the input stream and returns it as an int in the range of 0-255.
int
read(byte[] b, int off, int len)
This method read bytes from a stream and stores them into a caller supplied buffer.
void
reset()
This method resets a stream to the point where the mark() method was called.
long
skip(long n)
This method skips the specified number of bytes in the stream.

Methods inherited from class java.io.InputStream

available, close, mark, markSupported, read, read, read, reset, skip

Methods inherited from class java.lang.Object

clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

count

protected int count

mark

protected int mark

pos

protected int pos

ptr

protected RawData ptr

Constructor Details

CoreInputStream

public CoreInputStream(Core core)

Method Details

available

public int available()
This method returns the number of bytes that can be read from this stream before a read can block. A return of 0 indicates that blocking might (or might not) occur on the very next read attempt.

This method always returns 0 in this class

Overrides:
available in interface InputStream
Returns:
The number of bytes that can be read before blocking could occur

mark

public void mark(int readAheadLimit)
This method marks a position in the input to which the stream can be "reset" by calling the reset() method. The parameter @code{readlimit} is the number of bytes that can be read from the stream after setting the mark before the mark becomes invalid. For example, if mark() is called with a read limit of 10, then when 11 bytes of data are read from the stream before the reset() method is called, then the mark is invalid and the stream object instance is not required to remember the mark.

This method does nothing in this class, but subclasses may override it to provide mark/reset functionality.

Overrides:
mark in interface InputStream
Parameters:

markSupported

public boolean markSupported()
This method returns a boolean that indicates whether the mark/reset methods are supported in this class. Those methods can be used to remember a specific point in the stream and reset the stream to that point.

This method always returns false in this class, but subclasses can override this method to return true if they support mark/reset functionality.

Overrides:
markSupported in interface InputStream
Returns:
true if mark/reset functionality is supported, false otherwise

read

public int read()
This method reads an unsigned byte from the input stream and returns it as an int in the range of 0-255. This method also will return -1 if the end of the stream has been reached.

This method will block until the byte can be read.

Overrides:
read in interface InputStream
Returns:
The byte read or -1 if end of stream

read

public int read(byte[] b,
                int off,
                int len)
This method read bytes from a stream and stores them into a caller supplied buffer. It starts storing the data at index off into the buffer and attempts to read len bytes. This method can return before reading the number of bytes requested. The actual number of bytes read is returned as an int. A -1 is returned to indicate the end of the stream.

This method will block until some data can be read.

This method operates by calling the single byte read() method in a loop until the desired number of bytes are read. The read loop stops short if the end of the stream is encountered or if an IOException is encountered on any read operation except the first. If the first attempt to read a bytes fails, the IOException is allowed to propagate upward. And subsequent IOException is caught and treated identically to an end of stream condition. Subclasses can (and should if possible) override this method to provide a more efficient implementation.

Overrides:
read in interface InputStream
Parameters:
b - The array into which the bytes read should be stored
off - The offset into the array to start storing bytes
len - The requested number of bytes to read
Returns:
The actual number of bytes read, or -1 if end of stream.

reset

public void reset()
This method resets a stream to the point where the mark() method was called. Any bytes that were read after the mark point was set will be re-read during subsequent reads.

This method always throws an IOException in this class, but subclasses can override this method if they provide mark/reset functionality.

Overrides:
reset in interface InputStream

skip

public long skip(long n)
This method skips the specified number of bytes in the stream. It returns the actual number of bytes skipped, which may be less than the requested amount.

This method reads and discards bytes into a byte array until the specified number of bytes were skipped or until either the end of stream is reached or a read attempt returns a short count. Subclasses can override this metho to provide a more efficient implementation where one exists.

Overrides:
skip in interface InputStream
Parameters:
n - The requested number of bytes to skip
Returns:
The actual number of bytes skipped.

Copyright (C) 2001 Free Software Foundation This file is part of libgcj. This software is copyrighted work licensed under the terms of the Libgcj License. Please consult the file "LIBGCJ_LICENSE" for details.