/**
* Copyright (C) 2009-2010 Wilfred Springer
*
* This file is part of Preon.
*
* Preon 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.
*
* Preon 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
* Preon; 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 org.codehaus.preon.codec;
import org.codehaus.preon.el.Expression;
import org.codehaus.preon.el.Expressions;
import org.codehaus.preon.*;
import org.codehaus.preon.annotation.BoundString;
import org.codehaus.preon.buffer.BitBuffer;
import java.nio.charset.Charset;
import java.lang.reflect.AnnotatedElement;
/**
* A {@link CodecFactory} generating {@link Codecs} capable of generating String from {@link BitBuffer} content.
*
* @author Wilfred Springer
*/
public class StringCodecFactory implements CodecFactory {
@SuppressWarnings("unchecked")
public <T> Codec<T> create(AnnotatedElement metadata, Class<T> type,
ResolverContext context) {
if (metadata == null) {
return null;
}
BoundString settings = metadata.getAnnotation(BoundString.class);
if (String.class.equals(type) && settings != null) {
try {
Charset charset; // Encodings are now given as strings, and turned into Charsets
charset = Charset.availableCharsets().get(settings.encoding());
// This throws a NullPointerException if the Charset can't be found
if (settings.size().length() > 0) {
Expression<Integer, Resolver> expr;
expr = Expressions.createInteger(context, settings.size());
return (Codec<T>) new FixedLengthStringCodec(
charset, //Note that this is a Charset, not an Encoding
expr,
settings.match(),
settings.converter().newInstance());
} else {
return (Codec<T>) new NullTerminatedStringCodec(
charset, //Note that this is a Charset, not an Encoding
settings.match(),
settings.converter().newInstance());
}
} catch (InstantiationException e) {
throw new CodecConstructionException(e.getMessage());
} catch (IllegalAccessException e) {
throw new CodecConstructionException(e.getMessage());
} catch (NullPointerException e) {
throw new CodecConstructionException(
"Unsupported encoding: "+e.getMessage());
}
} else {
return null;
}
}
}