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/*
Grr RSS Reader
Copyright (C) 2006, 2007 Guenther Noack <guenther@unix-ag.uni-kl.de>
Copyright (C) 2009 GNUstep Application Team
Riccardo Mottola
This application 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 3 of the License, or (at your option) any later version.
This application 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
Library General Public License for more details.
You should have received a copy of the GNU General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA.
*/
#import "Database.h"
#import "NSBundle+Extensions.h"
#ifdef __APPLE__
#import "GNUstep.h"
#endif
static id<Database> sharedDatabase = nil;
NSString* const GrrDatabasePluginNameDefaults = @"DatabasePluginName";
NSString* const DatabaseChangeNotification = @"DatabaseChangeNotification";
@implementation Database
+(id<Database>) shared
{
if (sharedDatabase == nil) {
id<Database> database;
// Find out the name of the database plugin to be loaded. The default is
// "TreeDatabase", but it can be overridden using the DatabasePluginName
// user default. For details, see the documentation on hacking a database
// in the documentation directory.
NSString* databasePluginName =
[[NSUserDefaults standardUserDefaults] objectForKey: GrrDatabasePluginNameDefaults];
if (databasePluginName == nil) {
databasePluginName = @"TreeDatabase";
}
database = [NSBundle instanceForBundleWithName: databasePluginName type: @"grrdb"];
NSAssert(database != nil, @"The database could not be loaded!");
NSAssert1(
[database conformsToProtocol: @protocol(Database)],
@"Database %@ does not conform to the database protocol.",
database
);
ASSIGN(sharedDatabase, database);
}
return sharedDatabase;
}
@end
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