synchronize

I'm new to PHP, so to get started I've decided to implement a singleton. While I am able to recreate the singleton pattern in php, but I am not sure how to implement double-checked locking. Is that even possible/needed in PHP. I have read somewhere that PHP is not multithreaded? Can someone confirm that? If it is multithreaded, can someone explain to me how lock() or synchronize() work in PHP? Thanks, Henry Alfred Share-nothing Architecture PHP has a Share-nothing Architecture : Like HTTP, each request is distinct Shared data is pushed down to the data-store layer Avoid front controllers This

Does ruby have the Java equivalent of synchronize keyword? I am using 1.9.1 and I don't quite see an elegant way to do this. It doesn't have the synchronize keyword, but you can get something very similar via the Monitor class. Here's an example from the Programming Ruby 1.8 book: require 'monitor' class Counter < Monitor attr_reader :count def initialize @count = 0 super end def tick synchronize do @count += 1 end end end c = Counter.new t1 = Thread.new { 100_000.times { c.tick } } t2 = Thread.new { 100_000.times { c.tick } } t1.join; t2.join c.count → 200000 The accepted answer doesn't

If I set an NSUserDefault object and try to access it before it has been synchronized , will I be able to access the object I just added? I've tried writing code to test it but I'm unsure of if the synchronization is happening without me knowing it. Yes, your application can access the saved preferences before the synchronize happens, if it is saved before the read cycle happens during the same run session of the application. For accessing the information during subsequent app launches it is necessary that the synchronisation happens. From the Apple docs: NSUserDefaults NSUserDefaults caches

What's the best javascript library, or plugin or extension to a library, that has implemented autosaving functionality? The specific need is to be able to 'save' a data grid. Think gmail and Google Documents' autosave. I don't want to reinvent the wheel if its already been invented. I'm looking for an existing implementation of the magical autoSave() function. Auto-Saving:pushing to server code that saves to persistent storage, usually a DB. The server code framework is outside the scope of this question. Note that I'm not looking for an Ajax library, but a library/framework a level higher:

My architect always says that Never synchronize on Boolean I am not able to understand the reason why and would really appreciate if someone could explain with an example as to why it is not a good practice. Reference Sample Code private Boolean isOn = false; private String statusMessage = "I'm off"; public void doSomeStuffAndToggleTheThing(){ // Do some stuff synchronized(isOn){ if(isOn){ isOn = false; statusMessage = "I'm off"; // Do everything else to turn the thing off } else { isOn = true; statusMessage = "I'm on"; // Do everything else to turn the thing on } } } I am not able to

I'm trying to understand what makes the lock in concurrency so important if one can use synchronized (this) . In the dummy code below, I can do either: synchronized the entire method or synchronize the vulnerable area ( synchronized(this){...} ) OR lock the vulnerable code area with a ReentrantLock. Code: private final ReentrantLock lock = new ReentrantLock(); private static List<Integer> ints; public Integer getResult(String name) { . . . lock.lock(); try { if (ints.size()==3) { ints=null; return -9; } for (int x=0; x<ints.size(); x++) { System.out.println("["+name+"] "+x+"/"+ints.size()+".