Stack Overflow
Stack Overflow

Questions tagged [singleton-methods]

Methods related to using of the singleton design pattern.

76 questions
1
vote
1 answer

Defining singleton methods

The following code is from the book Exceptional Ruby: starts_with_a = Object.new def starts_with_a. ===(e) /^A/ =~ e.name end If I comment out the first line where a new object is assigned to starts_with_a, then I get this error: `
':…
BrainLikeADullPencil
  • 11,313
  • 24
  • 78
  • 134
0
votes
2 answers

Coin Flip Statistics Program - undefined method

I'm trying to write a coin flip program where I can analyze the percentage of Heads flipped. I've gotten coin flip to work, just not the actually analyzing yet. The problem is when I created a Coin class in order to further break down the object…
Tony
  • 981
  • 5
  • 16
  • 30
0
votes
2 answers

Preventing a function from running multiple times in JavaScript

I'm working with some code that does this: var _init = false; this.init = function(){ if(_init) return; else _init = true; // Do a bunch of stuff here } It seems to me that there is a tiny race condition there that…
Trott
  • 66,479
  • 23
  • 173
  • 212
0
votes
1 answer

Is there any way to access the Parent object whom called a singleton method?

Given the following functional snippet I'm having trouble reducing the database queries: class User < ApplicationRecord belongs_to :account def self.do_something self.find_each do |user| puts "#{self.new.account.name}:#{user.name} did…
ted
  • 26
  • 2
0
votes
2 answers

Can clone object have same scope in singleton pattern?

In my case, I created a singleton object check below- class Foo { private static $obj = null; public static function create_obj () { if (self::$obj === null) { self::$obj = new self; } return…
Devraj verma
  • 407
  • 3
  • 14
0
votes
2 answers

Turn Employee Data List Into Singleton Class App

I have made an list employee data app in C# with functions like AddEmployee, DeleteEmployee, SearchEmployee. I would like to make the same program, but using Singleton design pattern. I know the structure of Singleton, but I messed up with making…
Kaloyan
  • 41
  • 5
0
votes
2 answers

Ruby: Singleton method of an instance variable inside a class

I am taking ruby-kickstart (Josh Cheek) challenges and even though I managed to pass all the test there is one thing I cannot understand. In the exercise you are being asked to override the << method for an instance variable. Specifically here is…
Yorgos Lamprakis
  • 761
  • 7
  • 16
0
votes
2 answers

Java - Infinity Loop Singleton class method call

I've a question about singleton class. When I call method next(), I expect that mProcessIndex will be increased but in reality, it won't so it causes stackoverflow error. So, the question is what is correct way to modify mProcessIndex value? Code…
Tuy Sotheara
  • 13
  • 5
0
votes
0 answers

Is it okay to have extra static methods in a singleton class?

I have written a singleton class (in objective-C) with methods: //shared instance +(void) sharedInstance; //method to get all feeds. -(NSArray*)getAllFeedItems; So to use this I have to call [[MyClass sharedInstance] getAllFeedItems]; Now instead…
Vishal
  • 147
  • 10
0
votes
6 answers

ruby hash within hash and a singleton method- cant access instance variable

#!/usr/bin/env ruby # this is the data I have @data = { :student => { :id => '123477', :first_name => 'Lazlo', :last_name =>'Fortunatus', :email=>'Lazlo@fortunatus.org' }, :contact_info => { :telephone=>'1 415 222-2222', …
hidden
  • 3,216
  • 8
  • 47
  • 69
0
votes
1 answer

Is it bad to wrap singleton instance methods in static methods?

Is there a con to implementing a singleton that wraps instance methods with static ones? For example: public void DoStuff() { instance._DoStuff(); } private void _DoStuff() { ... } And of course instance would be static. But it…
sk84z
  • 193
  • 1
  • 3
  • 10
0
votes
1 answer

how to maintain connection(created in singleton class)in the next page

I am trying to develop a windows chat app in wp8.1 in my first page i created a server connection in singleton class.I created another window for sending messages .using singleton how can i maintain the server connection in the next page also? my…
rose
  • 1
  • 3
0
votes
3 answers

static method vs singleton methods in multithreaded environment

I have a code sample with static methods and singleton class //code with static methods public class DataManager{ public static Object getDataObject(){ HashMap map = new HashMap(); //Some processing in collections //retrieval of…
Rishikesan Varudharajan
  • 693
  • 5
  • 20
0
votes
1 answer

When is a singleton class object garbage collected?

If a single instance of class is created using singleton pattern, if it is not referenced for a long time, if a GC finds an unrooted tree whose leaf is the Singleton instance, will it be garbage collected?
Free Coder
  • 459
  • 4
  • 19
0
votes
1 answer

Obj C: Unable to access singleton from debugger

So this is very odd. I just created a new singleton in my app, using the same pattern I have used for the numerous other singletons. This one, however, doesn't play nice with the debugger. Here's the code for getting the singleton: - (id)init { …
Darren Black
  • 1,030
  • 1
  • 9
  • 28
1 2 3
4
5 6