/*
* The Sun Project JXTA(TM) Software License
*
* Copyright (c) 2001-2007 Sun Microsystems, Inc. All rights reserved.
*
* 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.protocol;
import java.io.ByteArrayInputStream;
import java.io.InputStream;
import net.jxta.content.ContentID;
import net.jxta.document.ExtendableAdvertisement;
import net.jxta.id.ID;
import net.jxta.id.IDFactory;
import net.jxta.peergroup.PeerGroupID;
/**
* A ContentShareAdvertisement describes a ContentAdvertisement
* which is being shared by a specific provider implementation.
* It will always include a copy of the ContentAdvertisement of
* the Content being shared and will typically be extended by
* provider implementations to add information relating to how
* to contact the provider to obtain the content being advertised.
*
* @see net.jxta.content.Content
* @see net.jxta.protocol.ContentAdvertisement
*/
public abstract class ContentShareAdvertisement
extends ExtendableAdvertisement
implements Cloneable {
private ContentAdvertisement contentAdv;
private transient ID hashID;
/**
* Construct a new Codat Advertisement.
*/
public ContentShareAdvertisement() {
}
/**
* Returns the identifying type of this Advertisement.
*
* @return String the type of advertisement
*/
public static String getAdvertisementType() {
return "jxta:ContentShare";
}
/**
* {@inheritDoc}
*/
public final String getBaseAdvType() {
return getAdvertisementType();
}
/**
* Clone this ContentShareAdvertisement.
*
* @return a copy of this ContentShareAdvertisement
*/
@Override
public ContentShareAdvertisement clone() {
// All members are either immutable or never modified nor allowed to
// be modified: all accessors return clones.
try {
ContentShareAdvertisement clone =
(ContentShareAdvertisement) super.clone();
clone.setContentAdvertisement(getContentAdvertisement());
return clone;
} catch (CloneNotSupportedException impossible) {
return null;
}
}
/**
* Returns a unique ID for that advertisement (for indexing purposes).
* ContentShareAdvertisements will by default return an ID based on
* the combination of the base adtertisement type, the advertisement
* type, and the ContentID being advertised. This allows multiple
* ContentProviders instances to create unique advertisements that
* can coexist along side each other while preventing multiple
* variants of the same ContentID from the same provider. Some
* providers may want to override this method to return
* <code>null</code>, indicating that an ID based on a hash of the
* entire document should be used, insted.
*
* @return ContentID
*/
public ID getID() {
if (hashID == null) {
if (contentAdv == null) {
throw new IllegalStateException(
"cannot build ID: no ContentAdvertisement");
}
try {
// We have not yet built it. Do it now
ContentID id = contentAdv.getContentID();
StringBuilder builder = new StringBuilder();
builder.append(getBaseAdvType());
builder.append("_");
builder.append(getAdvType());
builder.append("_");
builder.append(id.toString());
String seed = builder.toString();
InputStream in = new ByteArrayInputStream(seed.getBytes());
hashID = IDFactory.newContentID(
(PeerGroupID) id.getPeerGroupID(),
id.isStatic(), seed.getBytes(), in);
} catch (Throwable thr) {
throw new IllegalStateException("cannot build ID", thr);
}
}
return hashID;
}
/**
* Gets the ID of the Content object being advertised by this document.
*
* @return ContentID for this advertisement
*/
public ContentID getContentID() {
if (contentAdv == null) {
return null;
} else {
return contentAdv.getContentID();
}
}
/**
* Returns the ContentAdvertisement which this share represents.
*
* @return the ContentAdvertisement of the Content being shared
*/
public ContentAdvertisement getContentAdvertisement() {
return contentAdv;
}
/**
* Sets the ContentAdvertisment which this share is representing.
*
* @param adv the ContentAdvertisement of the Content being shared
*/
public void setContentAdvertisement(ContentAdvertisement adv) {
contentAdv = adv;
}
/**
* {@inheritDoc}
*/
@Override
public boolean equals(Object otherObj) {
if (otherObj instanceof ContentShareAdvertisement) {
ContentShareAdvertisement otherSAdv =
(ContentShareAdvertisement) otherObj;
return otherSAdv.getID().equals(getID());
} else {
return false;
}
}
/**
* {@inheritDoc}
*/
@Override
public int hashCode() {
return getID().hashCode();
}
}