Initial revision

From-SVN: r102074

libjava/classpath/java/io/ObjectInput.java

@@ -0,0 +1,140 @@
+/* ObjectInput.java -- Read object data from a stream
+   Copyright (C) 1998,2003 Free Software Foundation, Inc.
+
+This file is 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, 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; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, 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. */
+
+
+package java.io; 
+
+/**
+  * This interface extends the <code>DataInput</code> interface to provide a
+  * facility to read objects as well as primitive types from a stream.  It
+  * also has methods that allow input to be done in a manner similar to
+  * <code>InputStream</code>
+  *
+  * @author Aaron M. Renn (arenn@urbanophile.com)
+  *
+  * @see DataInput
+  */
+public interface ObjectInput extends DataInput
+{
+  /**
+    * This method returns the number of bytes that can be read without
+    * blocking.
+    *
+    * @return The number of bytes available before blocking
+    *
+    * @exception IOException If an error occurs
+    */
+  int available() throws IOException;
+
+  /**
+    * This method reading a byte of data from a stream.  It returns that byte
+    * as an <code>int</code>.  This method blocks if no data is available 
+    * to be read.
+    * 
+    * @return The byte of data read
+    *
+    * @exception IOException If an error occurs
+    */
+  int read() throws IOException;
+
+  /**
+    * This method reads raw bytes and stores them them a byte array buffer.
+    * Note that this method will block if no data is available.  However, 
+    * it will not necessarily block until it fills the entire buffer.  That is,
+    * a "short count" is possible.
+    *
+    * @param buf The byte array to receive the data read
+    *
+    * @return The actual number of bytes read or -1 if end of stream
+    *
+    * @exception IOException If an error occurs
+    */
+  int read(byte[] buf) throws IOException;
+
+  /**
+    * This method reads raw bytes and stores them in a byte array buffer
+    * <code>buf</code> starting at position <code>offset</code> into the 
+    * buffer.  A 
+    * maximum of <code>len</code> bytes will be read.  Note that this method
+    * blocks if no data is available, but will not necessarily block until
+    * it can read <code>len</code> bytes of data.  That is, a "short count" is
+    * possible.
+    *
+    * @param buf The byte array to receive the data read
+    * @param offset The offset into <code>buf</code> to start storing data
+    * @param len The maximum number of bytes to read
+    *
+    * @return The actual number of bytes read or -1 if end of stream
+    *
+    * @exception IOException If an error occurs
+    */
+  int read(byte[] buf, int offset, int len) throws IOException;
+
+  /**
+    * Reads an object instance and returns it.  If the class for the object
+    * being read cannot be found, then a <code>ClassNotFoundException</code>
+    * will be thrown.
+    *
+    * @return The object instance that was read
+    *
+    * @exception ClassNotFoundException If a class for the object cannot be 
+    * found
+    * @exception IOException If any other error occurs
+    */
+  Object readObject() 
+    throws ClassNotFoundException, IOException;
+
+  /**
+    * This method causes the specified number of bytes to be read and
+    * discarded.  It is possible that fewer than the requested number of bytes
+    * will actually be skipped.
+    *
+    * @param numBytes The number of bytes to skip
+    *
+    * @return The actual number of bytes skipped
+    *
+    * @exception IOException If an error occurs
+    */
+  long skip(long numBytes) throws IOException;
+
+  /**
+    * This method closes the input source
+    *
+    * @exception IOException If an error occurs
+    */
+  void close() throws IOException;
+}