001 /* Readable.java -- A character source
002 Copyright (C) 2004, 2005 Free Software Foundation
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038 package java.lang;
039
040 import java.io.IOException;
041 import java.nio.CharBuffer;
042 import java.nio.ReadOnlyBufferException;
043
044 /**
045 * A <code>Readable</code> object is simply a source for Unicode character
046 * data. On request, a <code>Readable</code> will provide its data in
047 * a supplied <code>CharBuffer</code>.
048 *
049 * @author Tom Tromey <tromey@redhat.com>
050 * @author Andrew John Hughes <gnu_andrew@member.fsf.org>
051 * @since 1.5
052 */
053 public interface Readable
054 {
055
056 /**
057 * Adds the character data supplied by this <code>Readable</code>
058 * to the specified character buffer. This method simply places
059 * each character into the buffer as supplied, using <code>put()</code>,
060 * without flipping or rewinding.
061 *
062 * @param buf the buffer to place the character data in.
063 * @return the number of <code>char</code> values placed in the buffer,
064 * or -1 if no more characters are available.
065 * @throws IOException if an I/O error occurs.
066 * @throws NullPointerException if buf is null.
067 * @throws ReadOnlyBufferException if buf is read only.
068 */
069 int read(CharBuffer buf)
070 throws IOException;
071
072 }