停止ExecutorService任务中的无限循环
问题内容：
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
class Task implements Callable<String> {
public String call() throws Exception {
String s = "initial";
try {
System.out.println("Started..");
/*for (int i=0;i<10000;i++) {
if (i % 2 == 0) {
System.out.println("Even");
}
}*/
boolean flag = true;
while(flag) {
}
System.out.println("Finished!");
s = "Done";
}
catch (RuntimeException e) {
s = "RuntimeException";
}
catch (Exception e) {
s = "Exception";
}
finally {
}
return s;
}
}
public class ExecutorServiceTest {
public static void main(String[] args) throws Exception {
ExecutorService executor = Executors.newSingleThreadExecutor();
List<Future<String>> result = executor.invokeAll(Arrays.asList(new Task()), 5, TimeUnit.SECONDS);
executor.shutdown();
Iterator<Future<String>> iter = result.iterator();
while (iter.hasNext()) {
System.out.println("Came here");
Future<String> fut = iter.next();
System.out.println(fut.get());
}
}
}
有没有一种方法可以停止执行无限循环的线程？
问题答案：
是的，您可以将替换flag（或在逻辑上&&）!Thread.currentThread().isInterrupted()。
这样，当任务取消时，循环将终止。
循环看起来像这样：
while(!Thread.currentThread().isInterrupted() && flag) {
/* Do work. */
}
使用应该是这样的：
ExecutorService executor = Executors.newSingleThreadExecutor();
Future<String> task = executor.submit(new Task());
String str;
try {
str = task.get(5, TimeUnit.SECONDS);
} finally {
task.cancel(true);
}
