initial implementation of NSValueTransformer

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@24238 72102866-910b-0410-8b05-ffd578937521

ChangeLog

@@ -1,3 +1,11 @@
+2006-12-25 Dr. H. Nikolaus Schaller
+
+	* Headers/Foundation/NSValueTransformer.h:
+	* Headers/Foundation/Foundation.h:
+	* Source/NSValueTransformer.h:
+	* Source/GNUmakefile:
+	Initial implementation of NSValueTransformer.
+
 2006-12-25  Richard Frith-Macdonald <rfm@gnu.org>
 
 	* Headers/Additions/GNUstep/GSVersionMacros.h:

Headers/Foundation/Foundation.h

@@ -117,6 +117,7 @@
 #import	<Foundation/NSURLResponse.h>
 #import	<Foundation/NSUserDefaults.h>
 #import	<Foundation/NSValue.h>
+#import	<Foundation/NSValueTransformer.h>
 #import	<Foundation/NSXMLParser.h>
 #import	<Foundation/NSZone.h>
 

Headers/Foundation/NSValueTransformer.h

@@ -0,0 +1,78 @@
+/* Interface for NSValueTransformer for GNUStep
+   Copyright (C) 2006 Free Software Foundation, Inc.
+
+   Written Dr. H. Nikolaus Schaller
+   Created on Mon Mar 21 2005.
+   
+   This file is part of the GNUstep Base Library.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public
+   License as published by the Free Software Foundation; either
+   version 2 of the License, or (at your option) any later version.
+   
+   This library 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 Library General Public
+   License along with this library; if not, write to the Free
+   Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02111 USA.
+   */ 
+
+#ifndef __NSValueTransformer_h_GNUSTEP_BASE_INCLUDE
+#define __NSValueTransformer_h_GNUSTEP_BASE_INCLUDE
+#import	<GNUstepBase/GSVersionMacros.h>
+
+#if OS_API_VERSION(100300,GS_API_LATEST) && GS_API_VERSION(010200,GS_API_LATEST)
+
+#import	<Foundation/NSObject.h>
+
+#if	defined(__cplusplus)
+extern "C" {
+#endif
+
+GS_EXPORT NSString* const NSNegateBooleanTransformerName;
+GS_EXPORT NSString* const NSIsNilTransformerName;
+GS_EXPORT NSString* const NSIsNotNilTransformerName; 
+GS_EXPORT NSString* const NSUnarchiveFromDataTransformerName;
+
+@class NSString;
+
+@interface NSValueTransformer : NSObject
+
++ (BOOL) allowsReverseTransformation;
++ (void) setValueTransformer: (NSValueTransformer *)transformer
+		     forName: (NSString *)name;
++ (Class) transformedValueClass;
++ (NSValueTransformer *) valueTransformerForName: (NSString *)name;
++ (NSArray *) valueTransformerNames;
+
+- (id) reverseTransformedValue: (id)value;
+- (id) transformedValue: (id)value;
+
+@end
+
+// builtin transformers
+
+@interface NSNegateBooleanTransformer : NSValueTransformer
+@end
+
+@interface NSIsNilTransformer : NSValueTransformer
+@end
+
+@interface NSIsNotNilTransformer : NSValueTransformer
+@end
+
+@interface NSUnarchiveFromDataTransformer : NSValueTransformer
+@end
+
+#if	defined(__cplusplus)
+}
+#endif
+
+#endif	/* OS_API_VERSION */
+
+#endif /* __NSValueTransformer_h_GNUSTEP_BASE_INCLUDE */

Source/GNUmakefile

@@ -243,6 +243,7 @@ NSURLResponse.m \
 NSURLHandle.m \
 NSUserDefaults.m \
 NSValue.m \
+NSValueTransformer.m \
 NSXMLParser.m \
 NSZone.m \
 externs.m \
@@ -369,6 +370,7 @@ NSURLResponse.h \
 NSUserDefaults.h \
 NSUtilities.h \
 NSValue.h \
+NSValueTransformer.h \
 NSXMLParser.h \
 NSZone.h
 

Source/NSValueTransformer.m

@@ -0,0 +1,175 @@
+/* Implementation for NSValueTransformer for GNUStep
+   Copyright (C) 2006 Free Software Foundation, Inc.
+
+   Written Dr. H. Nikolaus Schaller
+   Created on Mon Mar 21 2005.
+   
+   This file is part of the GNUstep Base Library.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public
+   License as published by the Free Software Foundation; either
+   version 2 of the License, or (at your option) any later version.
+   
+   This library 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 Library General Public
+   License along with this library; if not, write to the Free
+   Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02111 USA.
+   */ 
+
+#import "Foundation/Foundation.h"
+
+@implementation NSValueTransformer
+
+NSString * const NSNegateBooleanTransformerName
+  = @"NSNegateBooleanTransformerName";
+NSString * const NSIsNilTransformerName
+  = @"NSIsNilTransformerName";
+NSString * const NSIsNotNilTransformerName
+  = @"NSIsNotNilTransformerName"; 
+NSString * const NSUnarchiveFromDataTransformerName
+  = @"NSUnarchiveFromDataTransformerName";
+
+// non-abstract methods
+
+static NSMutableDictionary *names;
+
++ (void) setValueTransformer: (NSValueTransformer *)transformer
+		     forName: (NSString *)name
+{
+  if (names == nil)
+    {
+      [self valueTransformerNames];	// allocate if needed
+    }
+  [names setObject: transformer forKey: name];
+}
+
++ (NSValueTransformer *) valueTransformerForName: (NSString *)name
+{
+  return [names objectForKey: name];
+}
+
++ (NSArray *) valueTransformerNames;
+{
+  if (names == nil)
+    {
+      names = [[NSMutableDictionary alloc] init];
+    }
+  return [names allKeys];
+}
+
+// abstract methods (must be implemented in subclasses)
+
++ (BOOL) allowsReverseTransformation
+{
+  [self subclassResponsibility: _cmd];
+  return NO;
+}
+
++ (Class) transformedValueClass
+{
+  return [self subclassResponsibility: _cmd];
+}
+
+- (id) reverseTransformedValue: (id)value
+{
+  return [self subclassResponsibility: _cmd];
+}
+
+- (id) transformedValue: (id)value
+{
+  return [self subclassResponsibility: _cmd];
+}
+
+@end
+
+// builtin transformers
+
+@implementation NSNegateBooleanTransformer
+
++ (BOOL) allowsReverseTransformation
+{
+  return YES;
+}
++ (Class) transformedValueClass
+{
+  return [NSNumber class];
+}
+- (id) reverseTransformedValue: (id) value
+{
+  return [NSNumber numberWithBool: ![value boolValue]];
+}
+- (id) transformedValue: (id)value
+{
+  return [NSNumber numberWithBool: ![value boolValue]];
+}
+
+@end
+
+@implementation NSIsNilTransformer
+
++ (BOOL) allowsReverseTransformation
+{
+  return NO;
+}
++ (Class) transformedValueClass
+{
+  return [NSNumber class];
+}
+- (id) reverseTransformedValue: (id)value
+{
+  return [self notImplemented: _cmd];
+}
+- (id) transformedValue: (id)value
+{
+  return [NSNumber numberWithBool: (value == nil)];
+}
+
+@end
+
+@implementation NSIsNotNilTransformer
+
++ (BOOL) allowsReverseTransformation
+{
+  return NO;
+}
++ (Class) transformedValueClass
+{
+  return [NSNumber class];
+}
+- (id) reverseTransformedValue: (id)value
+{
+  return [self notImplemented: _cmd];
+}
+- (id) transformedValue: (id)value
+{
+  return [NSNumber numberWithBool: (value != nil)];
+}
+
+@end
+
+@implementation NSUnarchiveFromDataTransformer
+
++ (BOOL) allowsReverseTransformation
+{
+  return YES;
+}
++ (Class) transformedValueClass
+{
+  return [NSData class];
+}
+- (id) reverseTransformedValue: (id)value
+{
+  return [self notImplemented: _cmd];
+}
+- (id) transformedValue: (id)value
+{
+  return [self notImplemented: _cmd];
+}
+
+@end