是否可以同时从两个不同的线程在同一个import java.util.*;
public class CardDescription {
public static void main(String[] args) {
Card c1 = new Card("KS");
System.out.println("Your card is" + c1.getDescription());
}}
public class Card {
private String value;
private String suite;
private String string1;
private String string2;
public Card(String s1){
value = s1.substring(0, 1);
suite = s1.substring(1);
}
public String getDescription(){
if (value.equalsIgnoreCase("A")){
string1 = "Ace";
}
else if(value.equalsIgnoreCase("K")){
string1 = "King";
}
else if(value.equalsIgnoreCase("Q")){
string1 = "Queen";
}
else if(value.equalsIgnoreCase("J")){
string1 = "Jack";
}
else if(value.equals("10")){
string1 = "Ten";
}
else if(value.equals("9")){
string1 = "Nine";
}
else if(value.equals("8")){
string1 = "Eight";
}
else if(value.equals("7")){
string1 = "Seven";
}
else if(value.equals("6")){
string1 = "Six";
}
else if(value.equals("5")){
string1 = "Five";
}
else if(value.equals("4")){
string1 = "Four";
}
else if(value.equals("3")){
string1 = "Three";
}
else if(value.equals("2")){
string1 = "Two";
}
if(suite.equalsIgnoreCase("D")){
string2 = "Diamonds";
}
else if(suite.equalsIgnoreCase("H")){
string2 = "Hearts";
}
else if(suite.equalsIgnoreCase("S")){
string2 = "Spades";
}
else if(suite.equalsIgnoreCase("C")){
string2 = "Clubs";
}
return string1 + " of " + string2;
}
}
上调用Wait()？
例如，以下代码是否有效：
Task动机：
我实现了一个控制器，它最终将请求序列化到串口，并处理来自端口的通知。请求可以从不同的线程发送，它们应该能够等待结果（或异常），但可以选择异步工作。
我考虑上面的设计，因为private BlockingCollection<Task> _queue = new BlockingCollection<Task>();
private Thread _taskPumpThread;
...
private void Run()
{
_taskPumpThread= new Thread(() => TaskPump(...));
_taskPumpThread.Start();
DoNothing();
}
private void DoNothing()
{
Task doNothing = new Task(() => Console.WriteLine("Doing nothing"));
queue.Add(doNothing);
doNothing.Wait(); // no try-catch for brevity
}
private void TaskPump(CancellationToken token)
{
while (!token.IsCancellationRequested)
{
Task task = queue.Take();
task.Start();
task.Wait();
}
}
可以很好地处理所有情况（同步结果，异步调用和异常）。
可以找到相关但不相同的问题here。
答案 0 :(得分：6)
我会限制自己回答你非常具体的问题。
如果您运行以下简短程序，您会看到答案是是，您可以让多个线程等待同一任务：
public static void Main(string[] args)
{
Task t = Task.Delay(10000);
new Thread(() => { ThreadRun(t); }).Start();
new Thread(() => { ThreadRun(t); }).Start();
Console.WriteLine("Main thread exits"); // this prints immediately.
}
private static void ThreadRun(Task t)
{
t.Wait();
Console.WriteLine(Thread.CurrentThread.ManagedThreadId + " finished waiting"); // this prints about 10 seconds later.
}