gnu.javax.crypto.sasl

Class SaslInputStream

Implemented Interfaces:
AutoCloseable, Closeable

public class SaslInputStream
extends InputStream

An input stream that uses either a SaslClient or a SaslServer to process the data through these entities' security layer filter(s).

Constructor Summary

SaslInputStream(SaslClient client, InputStream source)
SaslInputStream(SaslServer server, InputStream source)

Method Summary

int
available()
This method returns the number of bytes that can be read from this stream before a read can block.
void
close()
This method closes the stream.
int
read()
Reads the next byte of data from the input stream.
int
read(byte[] b, int off, int len)
Reads up to len bytes of data from the underlying source input stream into an array of bytes.

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

Constructor Details

SaslInputStream

public SaslInputStream(SaslClient client,
                       InputStream source)
            throws IOException

SaslInputStream

public SaslInputStream(SaslServer server,
                       InputStream source)
            throws IOException

Method Details

available

public int available()
            throws IOException
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
Throws:
IOException - If an error occurs

close

public void close()
            throws IOException
This method closes the stream. Any futher attempts to read from the stream may generate an IOException

This method does nothing in this class, but subclasses may override this method in order to provide additional functionality.

Specified by:
close in interface Closeable
close in interface AutoCloseable
Overrides:
close in interface InputStream
Throws:
IOException - If an error occurs, which can only happen in a subclass

read

public int read()
            throws 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.

From a SASL mechanism provider's perspective, if a security layer has been negotiated, the underlying source is expected to contain SASL buffers, as defined in RFC 2222. Four octets in network byte order in the front of each buffer identify the length of the buffer. The provider is responsible for performing any integrity checking or other processing on the buffer before returning the data as a stream of octets. For example, the protocol driver's request for a single octet from the stream might; i.e. an invocation of this method, may result in an entire SASL buffer being read and processed before that single octet can be returned.

Overrides:
read in interface InputStream
Returns:
the next byte of data, or -1 if the end of the stream is reached.
Throws:
IOException - if an I/O error occurs.

read

public int read(byte[] b,
                int off,
                int len)
            throws IOException
Reads up to len bytes of data from the underlying source input stream into an array of bytes. An attempt is made to read as many as len bytes, but a smaller number may be read, possibly zero. The number of bytes actually read is returned as an integer.

This method blocks until input data is available, end of file is detected, or an exception is thrown.

If b is null, a NullPointerException is thrown.

If off is negative, or len is negative, or off+len is greater than the length of the array b, then an IndexOutOfBoundsException is thrown.

If len is zero, then no bytes are read and 0 is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at end of file, the value -1 is returned; otherwise, at least one byte is read and stored into b.

The first byte read is stored into element b[off], the next one into b[off+1], and so on. The number of bytes read is, at most, equal to len. Let k be the number of bytes actually read; these bytes will be stored in elements b[off] through b[off+k-1], leaving elements b[off+k] through b[off+len-1] unaffected.

In every case, elements b[0] through b[off] and elements b[off+len] through b[b.length-1] are unaffected.

If the first byte cannot be read for any reason other than end of file, then an IOException is thrown. In particular, an IOException is thrown if the input stream has been closed.

From the SASL mechanism provider's perspective, if a security layer has been negotiated, the underlying source is expected to contain SASL buffers, as defined in RFC 2222. Four octets in network byte order in the front of each buffer identify the length of the buffer. The provider is responsible for performing any integrity checking or other processing on the buffer before returning the data as a stream of octets. The protocol driver's request for a single octet from the stream might result in an entire SASL buffer being read and processed before that single octet can be returned.

Overrides:
read in interface InputStream
Parameters:
b - the buffer into which the data is read.
off - the start offset in array b at which the data is wricodeen.
len - the maximum number of bytes to read.
Returns:
the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.
Throws:
IOException - if an I/O error occurs.

SaslInputStream.java -- Copyright (C) 2003, 2006, 2010 Free Software Foundation, Inc. This file is a part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. GNU Classpath is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.