001/* ObjectOutput.java -- Interface for writing objects to a stream
002   Copyright (C) 1998, 2003 Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package java.io;
040
041/**
042  * This interface extends <code>DataOutput</code> to provide the additional
043  * facility of writing object instances to a stream.  It also adds some
044  * additional methods to make the interface more
045  * <code>OutputStream</code> like.
046  *
047  * @author Aaron M. Renn (arenn@urbanophile.com)
048  *
049  * @see DataOutput
050  */
051public interface ObjectOutput
052  extends DataOutput, AutoCloseable
053{
054  /**
055    * This method writes the specified byte to the output stream.
056    *
057    * @param b The byte to write.
058    *
059    * @exception IOException If an error occurs.
060    */
061  void write(int b) throws IOException;
062
063  /**
064    * This method writes all the bytes in the specified byte array to the
065    * output stream.
066    *
067    * @param buf The array of bytes to write.
068    *
069    * @exception IOException If an error occurs.
070    */
071  void write(byte[] buf) throws IOException;
072
073  /**
074    * This method writes <code>len</code> bytes from the specified array
075    * starting at index <code>offset</code> into that array.
076    *
077    * @param buf The byte array to write from.
078    * @param offset The index into the byte array to start writing from.
079    * @param len The number of bytes to write.
080    *
081    * @exception IOException If an error occurs.
082    */
083  void write(byte[] buf, int offset, int len)
084    throws IOException;
085
086  /**
087    * This method writes a object instance to a stream.  The format of the
088    * data written is determined by the actual implementation of this method
089    *
090    * @param obj The object to write
091    *
092    * @exception IOException If an error occurs
093    */
094  void writeObject(Object obj) throws IOException;
095
096  /**
097    * This method causes any buffered data to be flushed out to the underlying
098    * stream
099    *
100    * @exception IOException If an error occurs
101    */
102  void flush() throws IOException;
103
104  /**
105    * This method closes the underlying stream.
106    *
107    * @exception IOException If an error occurs
108    */
109  void close() throws IOException;
110
111} // interface ObjectOutput