Limit Java Method Execution Time

Annotate your methods with @Timeable annotation and every time their execution takes more than the allowed time, their thread will be interrupted:

public class Resource {
  @Timeable(limit = 5, unit = TimeUnit.SECONDS)
  public String load(URL url) {
    return url.openConnection().getContent();
  }
}

The thread running this method will be terminated if it takes more than five seconds.

It is important to note that in Java 1.5+, it is impossible to force thread termination: Why Are Thread.stop, Thread.suspend, Thread.resume, and Runtime.runFinalizersOnExit Deprecated? We can't just call Thread.stop() when a thread is over a specified time limit. The best thing we can do is to call Thread#interrupt() and hope that the thread itself is checking its Thread#isInterrupted() status. If you want to design your long-running methods in a way that @Timeable can terminate them, embed a checker into your most intessively used place. For example:

public class Resource {
  @Timeable(limit = 1, unit = TimeUnit.SECONDS)
  public String load(String resource) {
    while (true) {
      if (Thread.currentThread().isInterrupted()) {
        throw new IllegalStateException("time out");
      }
      // Execution as usual.
    }
  }
}

The mechanism is implemented with AOP/AspectJ. Read to know how to integrate it into your pom.xml.

This blog post gives more details about the internal implementation of the mechanism.