/* ********************************************************************** **
** Copyright notice **
** **
** (c) 2005-2009 RSSOwl Development Team **
** http://www.rssowl.org/ **
** **
** All rights reserved **
** **
** This program and the accompanying materials are made available under **
** the terms of the Eclipse Public License v1.0 which accompanies this **
** distribution, and is available at: **
** http://www.rssowl.org/legal/epl-v10.html **
** **
** A copy is found in the file epl-v10.html and important notices to the **
** license from the team is found in the textfile LICENSE.txt distributed **
** in this package. **
** **
** This copyright notice MUST APPEAR in all copies of the file! **
** **
** Contributors: **
** RSSOwl Development Team - initial API and implementation **
** **
** ********************************************************************** */
package org.rssowl.core.internal.persist;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.Platform;
import org.rssowl.core.persist.IPersistable;
import java.net.URI;
import java.net.URISyntaxException;
/**
* The abstract super-type of all Model Objects that are persisted. It offers
* the following features:
* <ul>
* <li>Lookup for <code>org.eclipse.core.runtime.IAdaptable</code> Adapters
* using the Platform's Adapter Registry. This allows dynamic API extension on
* Runtime without touching the Model Object's source.</li>
* </ul>
*
* @author bpasero
*/
public abstract class Persistable implements IPersistable {
/**
* Default constructor provided for deserialization purposes.
*/
protected Persistable() {}
/**
* If <code>uri</code> is <code>null</code>, returns <code>null</code>.
* Otherwise, tries to create a URI from <code>uri</code> and throws an
* IllegalStateException if this fails.
*
* @param uri
* @return a URI created from <code>uri</code>.
* @throws IllegalStateException
*/
protected final URI createURI(String uri) {
if (uri == null)
return null;
try {
return new URI(uri);
} catch (URISyntaxException e) {
throw new IllegalStateException("Somehow an invalid URI was stored with the value of '" + uri + "'", e); //$NON-NLS-1$ //$NON-NLS-2$
}
}
/**
* Returns the text representation of <code>uri</code> if <code>uri</code>
* is not <code>null</code>. Returns <code>null</code> otherwise.
*
* @param uri
* @return the text representation of <code>uri</code> or <code>null</code>.
*/
protected final String getURIText(URI uri) {
return uri == null ? null : uri.toString();
}
/**
* Copies the contents of <code>listMergeResult</code> into
* <code>mergeResult</code> and returns whether there were any structural
* changes in <code>listMergeResult</code>.
*
* @param mergeResult
* @param listMergeResult
* @return <code>true</code> if there were structural changes in
* <code>listMergeResult</code>. Returns <code>false</code> otherwise.
*/
protected final boolean processListMergeResult(MergeResult mergeResult, ComplexMergeResult< ? > listMergeResult) {
mergeResult.addAll(listMergeResult);
if (listMergeResult.isStructuralChange())
return true;
return false;
}
/**
* Returns an object which is an instance of the given class associated with
* this object. Returns <code>null</code> if no such object can be found.
* <p>
* This implementation of the method declared by <code>IAdaptable</code>
* passes the request along to the platform's adapter manager; roughly
* <code>Platform.getAdapterManager().getAdapter(this, adapter)</code>.
* Subclasses may override this method (however, if they do so, they should
* invoke the method on their superclass to ensure that the Platform's adapter
* manager is consulted).
* </p>
*
* @param adapter the class to adapt to
* @return the adapted object or <code>null</code>
* @see IAdaptable#getAdapter(Class)
* @see Platform#getAdapterManager()
*/
@SuppressWarnings("unchecked")
public Object getAdapter(Class adapter) {
return Platform.getAdapterManager().getAdapter(this, adapter);
}
}