synchronization

问题 I'm using java.util.Timer to schedule a periodic task. At one point, I'd like to shut it down, and wait for it to finish . Timer.cancel() will prevent any future tasks from running. How do I make sure any tasks are not running at the moment (or wait for them if they are?) I can introduce external synchronization mechanisms, but I don't see how they can cover all cases. For example, if I synchronize on some Monitor within the task, I still miss the case when the task just started executing but

问题 I'm using java.util.Timer to schedule a periodic task. At one point, I'd like to shut it down, and wait for it to finish . Timer.cancel() will prevent any future tasks from running. How do I make sure any tasks are not running at the moment (or wait for them if they are?) I can introduce external synchronization mechanisms, but I don't see how they can cover all cases. For example, if I synchronize on some Monitor within the task, I still miss the case when the task just started executing but

问题 My application needs to synchronize some data from server. I added necessary classes (similarly to SampleSyncAdapter) now I can add account via "Settings/Sync and Accounts". But I want to have already added my account and working synchronization just after application is installed (I do not want user to do any manual changes in settings). How to do this? 回答1: There is Android AtLeap library which contains helper classes to use Account Authenticator. Have a look at it https://github.com

问题 I use Firebase to handle the Auth topic of my Android app. I also save a user profile on Firebase, that contain user id and extra options that user can update in the android app. At startup, the app check the auth, and auth. It reload the user profile (on Firebase) to then update my userInstance on the app. Firebase is set as offline capable at app level. The userInstance POJO is sync with Firebase at log and stop to be sync at unlog. I have a special parameter, in my user profile that I can

问题 What's the best way / least wait-causing way to synchronize read/write access to an instance variable in objective-c for iOS? The variable gets read and written very often (let's say 1000 times per second read and written). It is not important that changes take effect immediately. It is not even important that reads get consistent data with one-another, but writes must sooner or later be reflected in the data acquired by reads. Is there some data structure which allows this? I thought of this

问题 While discussing a Java synchronization question, someone made a comment that the following snippets are not equivalent (and may compile to different bytecodes): public synchronized void someMethod() { //stuff } and public void someMethod() { synchronized (this) { //stuff } } Are they equivalent? 回答1: They are equivalent in function, though the compilers I tested (Java 1.6.0_07 and Eclipse 3.4) generate different bytecode. The first generates: // access flags 33 public synchronized someMethod

问题 My use case: I have a 'MainApp' which does the syncing of files. I would like that 'MainApp' handles all server calls regarding syncing and other REST API calls such as document-sharing, etc. On the other hand, I would have a Finder Sync Extension which would show sync-status icon overlays. It would also have a file-context-menu-item 'Share' which would present a Share dialog where users can choose with whom to share the file. Questions: How should FinderSyncExtension and MainApp communicate?

问题 This question already has answers here : Is there an advantage to use a Synchronized Method instead of a Synchronized Block? (23 answers) Closed 2 years ago . What is the difference between a synchronized method and synchronized block in Java ? I have been searching the answer on the Net, people seem to be so unsure about this one :-( My take would be there is no difference between the two, except that the synch block might be more localized in scope and hence the lock will be of lesser time

问题 This question already has answers here : Is there an advantage to use a Synchronized Method instead of a Synchronized Block? (23 answers) Closed 2 years ago . What is the difference between a synchronized method and synchronized block in Java ? I have been searching the answer on the Net, people seem to be so unsure about this one :-( My take would be there is no difference between the two, except that the synch block might be more localized in scope and hence the lock will be of lesser time

问题 This question already has answers here : Is there an advantage to use a Synchronized Method instead of a Synchronized Block? (23 answers) Closed 2 years ago . What is the difference between a synchronized method and synchronized block in Java ? I have been searching the answer on the Net, people seem to be so unsure about this one :-( My take would be there is no difference between the two, except that the synch block might be more localized in scope and hence the lock will be of lesser time