NSObject+NSCodingSupport.md

NSObject+NSCodingSupport

Category that provides foundational support for object archiving and serialization in mulle-objc.

Methods

Version Control

• +version - Returns class version
• -version - Returns instance version

Class Substitution

• +classForCoder - Returns class for encoding
• -classForCoder - Returns instance-specific class
• +classNameForCoder - Returns class name for encoding

Object Replacement

• -replacementObjectForCoder: - Returns replacement for encoding
• -awakeAfterUsingCoder: - Post-decode processing

Usage Example

// Implementing NSCoding
@interface MyObject : NSObject <NSCoding>
@end

@implementation MyObject

- (void)encodeWithCoder:(NSCoder *)coder
{
    [coder encodeObject:self.name forKey:@"name"];
    [coder encodeInteger:self.value forKey:@"value"];
}

- (id)initWithCoder:(NSCoder *)coder
{
    self = [super init];
    if (self) {
        _name = [coder decodeObjectForKey:@"name"];
        _value = [coder decodeIntegerForKey:@"value"];
    }
    return self;
}

@end

Important Notes

1. Version Management

   • Increment versions properly
   • Handle all versions
   • Document changes

2. Data Migration

   • Convert between versions
   • Validate data
   • Handle missing fields

3. Error Handling

   • Validate decoded data
   • Handle corruption
   • Provide defaults

4. Compatibility

   • Version handling
   • Forward compatibility
   • Backward compatibility

5. Security

   • Data validation
   • Safe decoding
   • Secure storage