/*
* Copyright (c) 2001-2007 Sun Microsystems, Inc. All rights reserved.
*
* The Sun Project JXTA(TM) Software License
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. The end-user documentation included with the redistribution, if any, must
* include the following acknowledgment: "This product includes software
* developed by Sun Microsystems, Inc. for JXTA(TM) technology."
* Alternately, this acknowledgment may appear in the software itself, if
* and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must
* not be used to endorse or promote products derived from this software
* without prior written permission. For written permission, please contact
* Project JXTA at http://www.jxta.org.
*
* 5. Products derived from this software may not be called "JXTA", nor may
* "JXTA" appear in their name, without prior written permission of Sun.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SUN
* MICROSYSTEMS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* JXTA is a registered trademark of Sun Microsystems, Inc. in the United
* States and other countries.
*
* Please see the license information page at :
* <http://www.jxta.org/project/www/license.html> for instructions on use of
* the license in source files.
*
* ====================================================================
*
* This software consists of voluntary contributions made by many individuals
* on behalf of Project JXTA. For more information on Project JXTA, please see
* http://www.jxta.org.
*
* This license is based on the BSD license adopted by the Apache Foundation.
*/
package net.jxta.endpoint;
import net.jxta.document.MimeMediaType;
import net.jxta.logging.Logging;
import net.jxta.util.ClassFactory;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import java.util.Hashtable;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* This class is a class factory for Wire Format Messages. This class abstracts
* The implementation of Wire Format Messages and allows for construction based
* on the MimeType of InputStreams.
* <p/>
* The WireFormatMessageFactory extends the ClassFactory to register the
* various Message wire format implementations into a static hashtable. The
* factory is called with the Mime type requested to create the corresponding
* Wire Format type.
*
* @see net.jxta.endpoint.Message
* @see net.jxta.endpoint.WireFormatMessage
* @see net.jxta.util.ClassFactory
* @see net.jxta.document.MimeMediaType
*/
public final class WireFormatMessageFactory extends ClassFactory<MimeMediaType, WireFormatMessageFactory.Instantiator> {
/**
* Logger
*/
private static final Logger LOG = Logger.getLogger(WireFormatMessageFactory.class.getName());
/**
* The mime media type of preferred/default wire format.
*/
public static final MimeMediaType DEFAULT_WIRE_MIME = new MimeMediaType("application/x-jxta-msg").intern();
/**
* Interface for instantiators of wire format messages.
*/
public interface Instantiator {
/**
* Returns the list of mime types supported by this serialization. All of
* mimetypes in this list should have no mime type parameters.
*
* @return Returns the list of mime types supported by this serialization.
*/
public MimeMediaType[] getSupportedMimeTypes();
/**
* Returns a list of the content encodings supported by this serialization.
* These content encodings apply to both the overall coding of the message
* and to the encoding of individual elements.
*
* @return a list of the content encodings supported by this serialization.
*/
public MimeMediaType[] getSupportedContentEncodings();
/**
* Create a WireFormatMessage from an abstract message. It is an error
* (though lazily enforced) to modify the abstract message during the
* lifetime of the WireFormatMessage.
*
* @param msg the message for which a serialization is desired.
* @param type the the serialization form desired. This can include
* mime parameters to control options.
* @param preferedContentEncoding An array of acceptable message encodings
* in descending order of preference. any or none of these encoding options
* may be used. May be null for unencoded messages.
* @return a proxy object for the abstract message which is a
* representation of the message in its serialized form.
*/
public WireFormatMessage toWire(Message msg, MimeMediaType type, MimeMediaType[] preferedContentEncoding);
/**
* Create an abstract message from a serialization.
*
* @param is The message stream. Message serializations must either use
* internal data or EOF to determine the length of the stream.
* @param type Declared message type of the stream including any optional
* configuration parameters.
* @param contentEncoding Content encoding (including optional parameters)
* which has been applied to the message. May be null for unencoded messages.
* @return a proxy object for the abstract message which is a
* representation of the message in its serialized form.
* @throws java.io.IOException if an io error occurs
*/
public Message fromWire(InputStream is, MimeMediaType type, MimeMediaType contentEncoding) throws IOException;
/**
* Create an abstract message from a serialization.
*
* @param buffer The byte buffer. Message serializations must either use
* internal data or EOF to determine the length of the stream.
* @param type Declared message type of the stream including any optional
* configuration parameters.
* @param contentEncoding Content encoding (including optional parameters)
* which has been applied to the message. May be null for unencoded messages.
* @return a proxy object for the abstract message which is a
* representation of the message in its serialized form.
* @throws java.io.IOException if an io error occurs
*/
public Message fromBuffer(ByteBuffer buffer, MimeMediaType type, MimeMediaType contentEncoding) throws IOException;
}
/**
* This is the map of mime-types and constructors used by
* <CODE>newStructuredDocument</CODE>.
*/
private Map<MimeMediaType,Instantiator> encodings = new Hashtable<MimeMediaType,Instantiator>();
/**
* If true then the pre-defined set of StructuredDocument sub-classes has
* been registered from the property containing them.
*/
private volatile boolean loadedProperty = false;
/**
* This class is in fact a singleton. This is the instance that backs the
* static methods.
*/
private static WireFormatMessageFactory factory = new WireFormatMessageFactory();
/**
* Private constructor. This class is not meant to be instantiated except
* by itself.
*/
private WireFormatMessageFactory() {}
/**
* Registers the pre-defined set of WireFormatMessage sub-classes so that
* this factory can construct them.
*
* @return true if at least one of the WireFormatMessage sub-classes could
* be registered otherwise false.
*/
private synchronized boolean loadProviders() {
if (!factory.loadedProperty) {
factory.loadedProperty = registerProviders(WireFormatMessage.class.getName());
}
return factory.loadedProperty;
}
/**
* {@inheritDoc}
*/
@Override
protected Map<MimeMediaType,Instantiator> getAssocTable() {
return encodings;
}
/**
* {@inheritDoc}
*/
@Override
public Class<Instantiator> getClassOfInstantiators() {
// our key is the doctype names.
return Instantiator.class;
}
/**
* {@inheritDoc}
*/
@Override
public Class getClassForKey() {
// our key is the mime types.
return MimeMediaType.class;
}
/**
* {@inheritDoc}
*/
@Override
protected boolean registerAssoc(String className) {
boolean registeredSomething = false;
if (Logging.SHOW_FINE && LOG.isLoggable(Level.FINE)) {
LOG.fine("Registering : " + className);
}
try {
Class msgClass = Class.forName(className);
Instantiator instantiator = (Instantiator) (msgClass.getField("INSTANTIATOR").get(null));
MimeMediaType[] mimeTypes = instantiator.getSupportedMimeTypes();
for (MimeMediaType mimeType : mimeTypes) {
if (Logging.SHOW_FINER && LOG.isLoggable(Level.FINER)) {
LOG.finer(" Registering Type : " + mimeType);
}
registeredSomething |= registerInstantiator(mimeType, instantiator);
}
} catch (Exception all) {
if (Logging.SHOW_WARNING && LOG.isLoggable(Level.WARNING)) {
LOG.log(Level.WARNING, "Failed to register \'" + className + "\'", all);
}
}
return registeredSomething;
}
/**
* Register an instantiator object a mime-type of documents to be
* constructed.
*
* @param mimetype the mime-type associated.
* @param instantiator the instantiator that wants to be registered..
* @return boolean true if the instantiator for this mime-type is now
* registered. If there was already an instantiator this mime-type then
* false will be returned.
* @throws SecurityException there were permission problems registering
* the instantiator.
*/
public static boolean registerInstantiator(MimeMediaType mimetype, Instantiator instantiator) {
boolean registered = factory.registerAssoc(mimetype, instantiator);
return registered;
}
/**
* Constructs an instance of {@link WireFormatMessage} matching the type
* specified by the <CODE>type</CODE> parameter.
*
* @param msg the message for which a serialization is desired.
* @param type the the serialization form desired. This can include
* mime parameters to control options.
* @param preferedEncodings An array of acceptable message encodings
* in descending order of preference. any or none of these encoding options
* may be used. May be null for unencoded messages.
* @return a proxy object for the abstract message which is a
* representation of the message in its serialized form.
*/
public static WireFormatMessage toWire(Message msg, MimeMediaType type, MimeMediaType[] preferedEncodings) {
factory.loadProviders();
Instantiator instantiator = factory.getInstantiator(type.getBaseMimeMediaType());
return instantiator.toWire(msg, type, preferedEncodings);
}
/**
* Constructs an instance of <CODE>Message</CODE> from matching the type
* specified by the <CODE>type</CODE> parameter.
*
* @param is The message stream. Message serializations must either use
* internal data or EOF to determine the length of the stream.
* @param type Declared message type of the stream including any optional
* configuration parameters.
* @param contentEncoding Content encoding (including optional parameters)
* which has been applied to the message. May be null for unencoded messages.
* @return the new abstract message.
* @throws java.io.IOException if an io error occurs
*/
public static Message fromWire(InputStream is, MimeMediaType type, MimeMediaType contentEncoding) throws IOException {
factory.loadProviders();
Instantiator instantiator;
try {
instantiator = factory.getInstantiator(type.getBaseMimeMediaType());
} catch (NoSuchElementException badType) {
throw new IOException("Unable to deserialize message of type: " + type);
}
return instantiator.fromWire(is, type, contentEncoding);
}
/**
* Constructs an instance of <CODE>Message</CODE> from matching the type
* specified by the <CODE>type</CODE> parameter.
*
* @param buffer The message buffer. Message serializations must either use
* internal data or EOF to determine the length of the stream.
* @param type Declared message type of the stream including any optional
* configuration parameters.
* @param contentEncoding Content encoding (including optional parameters)
* which has been applied to the message. May be null for unencoded messages.
* @return the new abstract message.
* @throws java.io.IOException if an io error occurs
*/
public static Message fromBuffer(ByteBuffer buffer, MimeMediaType type, MimeMediaType contentEncoding) throws IOException {
factory.loadProviders();
Instantiator instantiator;
try {
instantiator = factory.getInstantiator(type.getBaseMimeMediaType());
} catch (NoSuchElementException badType) {
throw new IOException("Unable to deserialize message of type: " + type);
}
return instantiator.fromBuffer(buffer, type, contentEncoding);
}
}