gistfile2.txt

//
//  YAJLTopLevelParser.m
//
//  Created by John Wright on 03/29/10.
//  Copyright 2010. All rights reserved.
//
//  Permission is hereby granted, free of charge, to any person
//  obtaining a copy of this software and associated documentation
//  files (the "Software"), to deal in the Software without
//  restriction, including without limitation the rights to use,
//  copy, modify, merge, publish, distribute, sublicense, and/or sell
//  copies of the Software, and to permit persons to whom the
//  Software is furnished to do so, subject to the following
//  conditions:
//
//  The above copyright notice and this permission notice shall be
//  included in all copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
//  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
//  OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
//  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
//  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
//  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
//  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
//  OTHER DEALINGS IN THE SOFTWARE.
//

#import "YAJLTopLevelParser.h"


@interface YAJLTopLevelParser ()
- (void)_pop;
- (void)_popKey;
@end

NSInteger YAJLTopLevelParserStackCapacity = 20;

@implementation YAJLTopLevelParser


@synthesize parserStatus=parserStatus_, delegate=delegate_;

- (id)init {
	return [self initWithParserOptions:0];
}

- (id)initWithParserOptions:(YAJLParserOptions)parserOptions {
	if ((self = [super init])) {
		stack_ = [[NSMutableArray alloc] initWithCapacity:YAJLTopLevelParserStackCapacity];
		keyStack_ = [[NSMutableArray alloc] initWithCapacity:YAJLTopLevelParserStackCapacity];		
		parserStatus_ = YAJLParserStatusNone;
		parser_ = [[YAJLParser alloc] initWithParserOptions:parserOptions];
		parser_.delegate = self;
		firstChunkReceived_ = YES;
	}
	return self;
}

- (id)initWithData:(NSData *)data parserOptions:(YAJLParserOptions)parserOptions error:(NSError **)error {
	if ((self = [self initWithParserOptions:parserOptions])) {		
		[self parse:data error:error];
	}
	return self;
}

- (void)dealloc {
	[stack_ release];
	[keyStack_ release];
	parser_.delegate = nil;
	[parser_ release];	
	[super dealloc];
}

- (YAJLParserStatus)parse:(NSData *)data error:(NSError **)error {
	if (firstChunkReceived_ && [delegate_ respondsToSelector:@selector(parserWillStart:)]) {
			[delegate_ parserWillStart:self];
	} 
	
	parserStatus_ = [parser_ parse:data];
	if (error) *error = [parser_ parserError];
	if (*error) {
		NSLog(@"%@", *error);
	}
	
	if (parserStatus_ == YAJLParserStatusOK && [delegate_ respondsToSelector:@selector(parserDidEnd:)]) {
		[delegate_ parserDidEnd:self];
	}

	firstChunkReceived_ = NO;
	return parserStatus_;
}

#pragma mark Delegates

- (void)parser:(YAJLParser *)parser didAdd:(id)value {
	switch(currentType_) {
		case YAJLDecoderCurrentTypeArray:
			[array_ addObject:value];
			break;
		case YAJLDecoderCurrentTypeDict:
			NSParameterAssert(key_);
			[dict_ setObject:value forKey:key_];
			[self _popKey];
			break;
	}	
}

- (void)parser:(YAJLParser *)parser didMapKey:(NSString *)key {
	key_ = key;
	[keyStack_ addObject:key_]; // Push
}

- (void)_popKey {
	key_ = nil;
	[keyStack_ removeLastObject]; // Pop	
	if ([keyStack_ count] > 0) 
		key_ = [keyStaack_ objectAtIndex:[keyStack_ count]-1];	
}

- (void)parserDidStartDictionary:(YAJLParser *)parser {
	NSMutableDictionary *dict = [[NSMutableDictionary alloc] initWithCapacity:YAJLTopLevelParserStackCapacity];
	[stack_ addObject:dict]; // Push
	dict_ = dict;
	[dict release];
	currentType_ = YAJLDecoderCurrentTypeDict;	
}

- (void)parserDidEndDictionary:(YAJLParser *)parser {
	id value = [[stack_ objectAtIndex:[stack_ count]-1] retain];
	NSDictionary *dict = dict_;
	[self _pop];
	[self parser:parser didAdd:value];
	//our delegate is only interested in top level dictionaries
	if ([delegate_ respondsToSelector:@selector(parser:didAddTopLevelDictionary:)] && ([stack_ count] <= 1)) {
		[dict autorelease];
		[delegate_ parser:self didAddTopLevelDictionary:dict];
	} else {
		[value release];
	}

}

- (void)parserDidStartArray:(YAJLParser *)parser {
	//we want to start the stack when we see the first dictionary
	//of course this ignore json like [1, 2, 4];
	//but this parser is for streaming top level dictionaries
	if (dict_) {
		NSMutableArray *array = [[NSMutableArray alloc] initWithCapacity:YAJLTopLevelParserStackCapacity];
		[stack_ addObject:array]; // Push
		[array release];
		array_ = array;
		currentType_ = YAJLDecoderCurrentTypeArray;
	}
}

- (void)parserDidEndArray:(YAJLParser *)parser {
	if (dict_) {
		id value = [[stack_ objectAtIndex:[stack_ count]-1] retain];
		[self _pop];	
		[self parser:parser didAdd:value];
		[value release];
	}
}

- (void)_pop {
	[stack_ removeLastObject];
	array_ = nil;
	dict_ = nil;
	currentType_ = YAJLDecoderCurrentTypeNone;
	
	id value = nil;
	if ([stack_ count] > 0) value = [stack_ objectAtIndex:[stack_ count]-1];
	if ([value isKindOfClass:[NSArray class]]) {		
		array_ = (NSMutableArray *)value;
		currentType_ = YAJLDecoderCurrentTypeArray;
	} else if ([value isKindOfClass:[NSDictionary class]]) {		
		dict_ = (NSMutableDictionary *)value;
		currentType_ = YAJLDecoderCurrentTypeDict;
	}
}

@end

YAJLTopLevelParser.h

//
//  YAJLTopLevelParser.h
//
//  Created by John Wright on 03/29/10.
//  Copyright 2010. All rights reserved.
//
//  Permission is hereby granted, free of charge, to any person
//  obtaining a copy of this software and associated documentation
//  files (the "Software"), to deal in the Software without
//  restriction, including without limitation the rights to use,
//  copy, modify, merge, publish, distribute, sublicense, and/or sell
//  copies of the Software, and to permit persons to whom the
//  Software is furnished to do so, subject to the following
//  conditions:
//
//  The above copyright notice and this permission notice shall be
//  included in all copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
//  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
//  OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
//  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
//  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
//  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
//  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
//  OTHER DEALINGS IN THE SOFTWARE.
//

#import <Foundation/Foundation.h>
#import "YAJLParser.h"

typedef enum {
	YAJLDecoderCurrentTypeNone,
	YAJLDecoderCurrentTypeArray,
	YAJLDecoderCurrentTypeDict
} YAJLDecoderCurrentType;

extern NSInteger YAJLTopLevelParserStackCapacity;

@class YAJLTopLevelParser;

@protocol YAJLTopLevelParserDelegate <NSObject> 
@optional

/* Notifies the delegate that the parser is about to parse the 
 * the first chunk of JSON data.
 * Often a good time to open any resources for streaming,
 * such as a database handle
 */
- (void)parserWillStart:(YAJLTopLevelParser *)parser;

/* Pushes to the delegate a complete parsed top-level dictionary.
 * These are dictionaries located at the highest JSON Level or within a single
 * enclosing Array.
 *
 * This is a convenience function on top of the streaming json parser.
 * Usually the top level dictionaries are the chunks the delegate
 * prefers to work with.  They represent twitter entries or other API objects,
 * or perhaps database records.  If you need access to lower level 
 * JSON parsing notifications than set the property lowLevelDelegate.
 */
- (void)parser:(YAJLTopLevelParser *)parser didAddTopLevelDictionary:(NSDictionary *)dict;

/* Notifies the delegate that the parser completed parsing the last
 * chunk of JSON data successfully.
 * Often a good time to close or commit any resouces
 */
- (void)parserDidEnd:(YAJLTopLevelParser *)parser;

@end

/* Will stream complete top level Dictionaries to the delegate
 * releasing them after pushing them to the delegate.
 * This creates an efficient way to process one top level JSON object
 * (such as a Twitter status) at a time.
 */
@interface YAJLTopLevelParser : NSObject <YAJLParserDelegate> {
	YAJLParser *parser_;
	
	__weak id<YAJLTopLevelParserDelegate> delegate_;
	
	__weak NSMutableDictionary *dict_; // weak; if map in progress, points to the current map	
	__weak NSMutableArray *array_; // weak; If array in progress, points the current array
	__weak NSString *key_; // weak; If map in progress, points to current key
	
	NSMutableArray *stack_;
	NSMutableArray *keyStack_;
	
	YAJLDecoderCurrentType currentType_;
	
	YAJLParserStatus parserStatus_;
	
	BOOL firstChunkReceived_;
}
@property (readonly, nonatomic) YAJLParserStatus parserStatus;
@property (assign, nonatomic) id<YAJLTopLevelParserDelegate> delegate;

/*!
 Create document from data.
 @param data Data to parse
 @param parserOptions Parse options
 @param error Error to set on failure
 */
- (id)initWithData:(NSData *)data parserOptions:(YAJLParserOptions)parserOptions error:(NSError **)error;

/*!
 Create empty document with parser options.
 @param parserOptions Parse options
 */
- (id)initWithParserOptions:(YAJLParserOptions)parserOptions;

/*!
 Parse data.
 @param data Data to parse
 @param error Error to set on failure
 @result Parser status
 */
- (YAJLParserStatus)parse:(NSData *)data error:(NSError **)error;


@end