org.armedbear.lisp.ConcatenatedStream Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of abcl Show documentation
Show all versions of abcl Show documentation
Common Lisp implementation running on the JVM
/*
* ConcatenatedStream.java
*
* Copyright (C) 2004-2005 Peter Graves
* $Id$
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* 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 org.armedbear.lisp;
import static org.armedbear.lisp.Lisp.*;
public final class ConcatenatedStream extends Stream
{
LispObject streams;
ConcatenatedStream(LispObject streams)
{
super(Symbol.CONCATENATED_STREAM);
this.streams = streams;
isInputStream = true;
}
@Override
public boolean isCharacterInputStream()
{
if (streams == NIL)
return true;
return ((Stream)streams.car()).isCharacterInputStream();
}
@Override
public boolean isBinaryInputStream()
{
if (streams == NIL)
return true;
return ((Stream)streams.car()).isBinaryInputStream();
}
@Override
public boolean isCharacterOutputStream()
{
return false;
}
@Override
public boolean isBinaryOutputStream()
{
return false;
}
@Override
public LispObject typeOf()
{
return Symbol.CONCATENATED_STREAM;
}
@Override
public LispObject classOf()
{
return BuiltInClass.CONCATENATED_STREAM;
}
@Override
public LispObject typep(LispObject typeSpecifier)
{
if (typeSpecifier == Symbol.CONCATENATED_STREAM)
return T;
if (typeSpecifier == BuiltInClass.CONCATENATED_STREAM)
return T;
return super.typep(typeSpecifier);
}
@Override
public LispObject getElementType()
{
if (streams == NIL)
return NIL;
return ((Stream)streams.car()).getElementType();
}
@Override
public LispObject readCharNoHang(boolean eofError, LispObject eofValue)
{
if (streams == NIL) {
if (eofError)
return error(new EndOfFile(this));
else
return eofValue;
}
try
{
return _charReady() ? readChar(eofError, eofValue) : NIL;
}
catch (java.io.IOException e)
{
return error(new StreamError(this, e));
}
}
@Override
public LispObject listen()
{
if (streams == NIL)
return NIL;
Stream stream = (Stream)streams.car();
return stream.listen();
}
// Returns -1 at end of file.
@Override
protected int _readChar() throws java.io.IOException
{
int n;
if (streams == NIL)
return -1;
Stream stream = (Stream) streams.car();
n = stream._readChar();
if (n >= 0)
return n;
streams = streams.cdr();
return _readChar();
}
@Override
protected void _unreadChar(int n) throws java.io.IOException
{
if (streams == NIL)
error(new StreamError(this, "UNREAD-CHAR was invoked without a stream to unread into."));
Stream stream = (Stream)streams.car();
stream._unreadChar(n);
}
@Override
protected boolean _charReady() throws java.io.IOException
{
if (streams == NIL)
return false;
Stream stream = (Stream) streams.car();
if (stream._charReady())
return true;
LispObject remainingStreams = streams.cdr();
while (remainingStreams != NIL) {
stream = (Stream) remainingStreams.car();
if (stream._charReady())
return true;
remainingStreams = remainingStreams.cdr();
}
return false;
}
@Override
public void _writeChar(char c)
{
outputStreamError();
}
@Override
public void _writeChars(char[] chars, int start, int end)
{
outputStreamError();
}
@Override
public void _writeString(String s)
{
outputStreamError();
}
@Override
public void _writeLine(String s)
{
outputStreamError();
}
// Reads an 8-bit byte.
@Override
public int _readByte()
{
if (streams == NIL)
return -1;
Stream stream = (Stream) streams.car();
int n = stream._readByte();
if (n >= 0)
return n;
streams = streams.cdr();
return _readByte();
}
// Writes an 8-bit byte.
@Override
public void _writeByte(int n)
{
outputStreamError();
}
@Override
public void _finishOutput()
{
outputStreamError();
}
@Override
public void _clearInput()
{
// FIXME
}
private void outputStreamError()
{
error(new StreamError(this,
String.valueOf(this) + " is not an output stream."));
}
// ### make-concatenated-stream &rest streams => concatenated-stream
private static final Primitive MAKE_CONCATENATED_STREAM =
new Primitive("make-concatenated-stream", "&rest streams")
{
@Override
public LispObject execute(LispObject[] args)
{
LispObject streams = NIL;
for (int i = 0; i < args.length; i++) {
if (args[i] instanceof Stream) {
Stream stream = (Stream) args[i];
if (stream.isInputStream()) {
// streams[i] = (Stream) args[i];
streams = new Cons(stream, streams);
continue;
}
}
error(new TypeError(String.valueOf(args[i]) +
" is not an input stream."));
}
return new ConcatenatedStream(streams.nreverse());
}
};
// ### concatenated-stream-streams concatenated-stream => streams
private static final Primitive CONCATENATED_STREAM_STREAMS =
new Primitive("concatenated-stream-streams", "concatenated-stream")
{
@Override
public LispObject execute(LispObject arg)
{
if (arg instanceof ConcatenatedStream)
return ((ConcatenatedStream)arg).streams;
return type_error(arg, Symbol.CONCATENATED_STREAM);
}
};
}