PythonObjectOriented - Revision history

RobertBushman: /* Singleton */

2025-08-18T15:00:43Z

Singleton

← Older revision		Revision as of 15:00, 18 August 2025
Line 26:		Line 26:
	# this works like Java's toString()		# this works like Java's toString()
	return f'{self.filename} {self.data} {self.index}'		return f'{self.filename} {self.data} {self.index}'

			# natural sorting 1 (required)
			def __lt__(self, other):
			return self.age < other.age
			# natural sorting 2 (not required, I think)
			def __eq__(self, other):
			return self.age == other.age

	def load_data(self):		def load_data(self):

RobertBushman at 14:48, 18 August 2025

2025-08-18T14:48:40Z

← Older revision		Revision as of 14:48, 18 August 2025
Line 22:		Line 22:
	self.index = None		self.index = None
	self.load_data()		self.load_data()

			def __str__(self):
			# this works like Java's toString()
			return f'{self.filename} {self.data} {self.index}'

	def load_data(self):		def load_data(self):

RobertBushman: /* Singleton */

2023-11-03T04:41:13Z

Singleton

@@ Line 40: / Line 40: @@
 print(data_manager.get_data_by_key('some_key'))
 </syntaxhighlight>
 = Abstract Class =
 <syntaxhighlight lang="python" line>

RobertBushman: /* Singleton */

2023-11-03T04:39:55Z

Singleton

@@ Line 39: / Line 39: @@
 data_manager = DataManager('data.json')
 print(data_manager.get_data_by_key('some_key'))
 </syntaxhighlight>

RobertBushman: /* Singleton */

2023-11-03T04:38:36Z

Singleton

← Older revision		Revision as of 04:38, 3 November 2023
Line 1:		Line 1:
	[[Category:Python]]		[[Category:Python]]
	= Singleton =		= Singleton =
	<syntaxhighlight lang="python" ~~lines~~>		<syntaxhighlight lang="python" line>
	import json		import json
	from threading import Lock		from threading import Lock

RobertBushman: /* Singleton */

2023-11-03T04:38:28Z

Singleton

← Older revision		Revision as of 04:38, 3 November 2023
Line 1:		Line 1:
	[[Category:Python]]		[[Category:Python]]
	= Singleton =		= Singleton =
	</syntaxhighlight lang="python" lines>		<syntaxhighlight lang="python" lines>
	import json		import json
	from threading import Lock		from threading import Lock

RobertBushman: Created page with "Category:Python = Singleton = import json from threading import Lock class SingletonMeta(type): _instances = {} _lock: Lock = Lock() def call(cls, *args, **kwargs): with cls._lock: if cls not in cls._instances: instance = super().call(*args, **kwargs) cls._instances[cls] = instance return cls._instances[cls] class DataManager(metaclass=Sin..."

2023-11-03T04:38:19Z

Created page with "Category:Python = Singleton = </syntaxhighlight lang="python" lines> import json from threading import Lock class SingletonMeta(type): _instances = {} _lock: Lock = Lock() def __call__(cls, *args, **kwargs): with cls._lock: if cls not in cls._instances: instance = super().__call__(*args, **kwargs) cls._instances[cls] = instance return cls._instances[cls] class DataManager(metaclass=Sin..."

New page

[[Category:Python]]
= Singleton =
</syntaxhighlight lang="python" lines>
import json
from threading import Lock

class SingletonMeta(type):
_instances = {}
_lock: Lock = Lock()

def __call__(cls, *args, **kwargs):
with cls._lock:
if cls not in cls._instances:
instance = super().__call__(*args, **kwargs)
cls._instances[cls] = instance
return cls._instances[cls]

class DataManager(metaclass=SingletonMeta):
def __init__(self, filename):
self.filename = filename
self.data = None
self.index = None
self.load_data()

def load_data(self):
with open(self.filename, 'r') as file:
self.data = json.load(file)
self.index_data()

def index_data(self):
# Implement your indexing logic here.
# For example, if your data is a list of dicts:
self.index = {d['key']: d for d in self.data}

def get_data_by_key(self, key):
return self.index.get(key)

# Usage:
data_manager = DataManager('data.json')
print(data_manager.get_data_by_key('some_key'))
</syntaxhighlight>