synchronize

问题 I am Java newbie (and RoR developer). I have a simple program. Ball is shared amont players. Ball should be passed to random Player. Ok here goes the code: class Ball { private int currentPlayer; public void setCurrentPlayer( int currentPlayer, int fromWho ) { this.currentPlayer = currentPlayer; System.out.println( "Ball:setCurrentPlayer " + fromWho + " ---> " + currentPlayer ); } public int getCurrentPlayer() { return currentPlayer; } } class Player implements Runnable { private int myID;

问题 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 回答1: Share-nothing Architecture PHP has a Share-nothing Architecture: Like HTTP, each

问题 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. 回答1: 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 =

问题 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. 回答1: 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

问题 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

问题 I have a situation where I need a set of operations be enclosed into a single transaction and be thread safe from a MDB. If thread A executes the instruction 1, do not want other threads can read, at least not the same, data that thread A is processing. In the code below since IMAGE table contains duplicated data, coming from different sources, this will lead in a duplicated INFRANCTION. Situation that needs to be avoided. The actual solution that I found is declaring a new transaction for

问题 I am trying to figure out how (if possible) to set up multiple git repositories to behave in a specific way. Basically, we have multiple repositories for multiple clients, however they are meant to all share a system directory. When a change is made to the system directory for one client, it should be made to the system directory for all clients. Now for the complication, we have multiple environments that we use for a CI development system. We currently have a production environment, client

问题 I have a problem where I need x threads to wait until they have all reached a synchronization point. My solution uses the synchronise method below which is called by each threaded function when they need to synchronise. Is there a better way to do this? thread_count = 0 semaphore = threading.Semaphore() event = threading.Event() def synchronise(count): """ All calls to this method will block until the last (count) call is made """ with semaphore: thread_count += 1 if thread_count == count:

问题 Is PHP has synchronize mechanism like Java? In my project different users can continue with same transaction. As example, I send a mail with payment details page URL to different user. So they can view that page at same time. Also they can continue to same transaction. I want deny (Show message) that page for users when one user already view the page. In java we can use synchronize for object. How can i do it in php or zend framework? 回答1: PHP is NOT like Java. Each request run in a separate

问题 I have an activity with two galleries. I want to synchronise both galleries so when I'm moving in one gallery, I should move the other gallery to match the same item. I don't know how to accomplish this. I though it could be done by synchronising the onScroll event, I followed a good attempt on this, but it doesn't work. I assume it's because I'm not interested on the scroll event, maybe on the fling event? Anyway, I don't know which is the proper event to observe and how to implement this.