thread-safety

问题 This question already has answers here : What's the difference between the atomic and nonatomic attributes? (26 answers) Atomic properties vs thread-safe in Objective-C (5 answers) Closed 4 years ago . I have gone through many answers about atomic and non-atomic properties. But I'm not able to understand whether atomic properties are thread safe? Please explain it with an example. 回答1: Yes an / one atomic property is thread-safe. That is what atomicity stands for. CAUTION But neither are two

问题 I'm trying to print numbers 1-20 with two threads: Even thread - Print only even numbers. Odd thread - print only odd numbers. I also have a lock object for synchronization. My application is stuck. Can you tell me what is the problem? My code: public class runIt { public static void main(String[] args) { Odd odd = new Odd("odd thread"); Even even = new Even("even thread"); odd._t.start(); even._t.start(); try{ odd._t.join(); even._t.join(); } catch (InterruptedException e){ System.out

问题 In a single thread program, how are changes made by thread in core 1 made visible to another core 2, so that after a context switch the thread (now running on core 2) will have updated value? Consider the following example: The value in main memory for variable x is 10. The thread runs on core 1 and changes x to 5, which is still in cache and not yet flushed to main memory as we are not using any memory barrier. A context switch occurs and the thread moves from core 1 to core 2. The thread

问题 I am using RestTemplate along with its factory HttpComponentsClientHttpRequestFactory in one of my projects. In this project, I need to make a Http url call to my server which is running a restful service which returns back the response as a JSON String. Below is my code - public class GetUserClientData { public String getData(KeyHolder keys) { return new HTTPRequestAccess(keys).makeHttpRequest(); } } Below is my class which wraps the HttpClient part - public class HTTPRequestAccess { //

问题 I am using RestTemplate along with its factory HttpComponentsClientHttpRequestFactory in one of my projects. In this project, I need to make a Http url call to my server which is running a restful service which returns back the response as a JSON String. Below is my code - public class GetUserClientData { public String getData(KeyHolder keys) { return new HTTPRequestAccess(keys).makeHttpRequest(); } } Below is my class which wraps the HttpClient part - public class HTTPRequestAccess { //

问题 I have a table of Albums that is filterable and sortable by the user. Here is what that table looks like. As you can see, the columns are sortable, and there is a text box at the top, which is currently filtering for albums with the string "cu" in them: Everything works perfectly after the list of albums is populated . However, if I try to sort or filter while the album list is populating, I get a ConcurrentModificationException . The album list initially takes a few minutes to load for a

问题 I'm using C# on .NET 4.5 - Web API Self Host. Server-side I've a process that is not thread safe: it can serve one request at a time. How can I lock this resource (process) in the controller code, so that clients are served sequentially, waiting for the resource to be freed before using it? Something like: while(true){ if(!process.isLocked) break; } lock(process) do(work) unlock(process) warn(others) Any code snippet or suggestion are appreciated. Thanks in advance. 回答1: If you're looking for

问题 I'm using C# on .NET 4.5 - Web API Self Host. Server-side I've a process that is not thread safe: it can serve one request at a time. How can I lock this resource (process) in the controller code, so that clients are served sequentially, waiting for the resource to be freed before using it? Something like: while(true){ if(!process.isLocked) break; } lock(process) do(work) unlock(process) warn(others) Any code snippet or suggestion are appreciated. Thanks in advance. 回答1: If you're looking for

问题 I'm using HttpSession object in Spring MVC with @Autowired : public abstract class UserController { @Autowired public HttpSession session; @RequestMapping(value = { "" }, method = { RequestMethod.GET }) public ModelAndView index(){ User user=(User)session.getAttribute("loginUser"); } } is the session thread-safe? 回答1: What you get wired from Spring is just the HttpSession. There are no special thread safety guarantees. Implementations using HttpSession are not necessarily thread safe. See

问题 I'm using HttpSession object in Spring MVC with @Autowired : public abstract class UserController { @Autowired public HttpSession session; @RequestMapping(value = { "" }, method = { RequestMethod.GET }) public ModelAndView index(){ User user=(User)session.getAttribute("loginUser"); } } is the session thread-safe? 回答1: What you get wired from Spring is just the HttpSession. There are no special thread safety guarantees. Implementations using HttpSession are not necessarily thread safe. See