我知道为什么弃用Thread#stop()的原因(见http://download.oracle.com/javase/1.5.0/docs/guide/misc/threadPrimitiveDeprecation.html).它们以可能在ThreadDeath异常情况下被损坏的对象为中心,然后污染正在运行的JVM环境并可能导致细微的错误.

我对这个对JVM工作有更深入了解的人的问题是：如果需要停止的线程没有任何(明显的)监视器或对程序其余部分使用的对象的引用,那么可以使用Thread#stop()吗？

我创建了一个相当防御的解决方案,能够处理与超时匹配的正则表达式.我会很高兴任何评论或评论,尤其是尽管我努力避免它们,这种方法可能导致的问题.

谢谢！

import java.util.concurrent.Callable;

public class SafeRegularExpressionMatcher {

    // demonstrates behavior for regular expression running into catastrophic backtracking for given input
    public static void main(String[] args) {
        SafeRegularExpressionMatcher matcher = new SafeRegularExpressionMatcher(
                "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx","(x+x+)+y",2000);
        System.out.println(matcher.matches());
    }

    final String stringToMatch;

    final String regularExpression;

    final int timeoutMillis;

    public SafeRegularExpressionMatcher(String stringToMatch,String regularExpression,int timeoutMillis) {
        this.stringToMatch = stringToMatch;
        this.regularExpression = regularExpression;
        this.timeoutMillis = timeoutMillis;
    }

    public Boolean matches() {
        CallableThread<Boolean> thread = createSafeRegularExpressionMatchingThread();
        Boolean result = tryToGetResultFromThreadWithTimeout(thread);
        return result;
    }

    private CallableThread<Boolean> createSafeRegularExpressionMatchingThread() {
        final String stringToMatchForUseInThread = new String(stringToMatch);
        final String regularExpressionForUseInThread = new String(regularExpression);
        Callable<Boolean> callable = createRegularExpressionMatchingCallable(stringToMatchForUseInThread,regularExpressionForUseInThread);
        CallableThread<Boolean> thread = new CallableThread<Boolean>(callable);
        return thread;
    }

    private Callable<Boolean> createRegularExpressionMatchingCallable(final String stringToMatchForUseInThread,final String regularExpressionForUseInThread) {
        Callable<Boolean> callable = new Callable<Boolean>() {
            public Boolean call() throws Exception {
                return Boolean.valueOf(stringToMatchForUseInThread.matches(regularExpressionForUseInThread));
            }
        };
        return callable;
    }

    private Boolean tryToGetResultFromThreadWithTimeout(CallableThread<Boolean> thread) {
        startThreadAndApplyTimeout(thread);
        Boolean result = processThreadResult(thread);
        return result;
    }

    private void startThreadAndApplyTimeout(CallableThread<Boolean> thread) {
        thread.start();
        try {
            thread.join(timeoutMillis);
        } catch (InterruptedException e) {
            throwRuntimeException("Interrupt",e);
        }
    }

    private Boolean processThreadResult(CallableThread<Boolean> thread) {
        Boolean result = null;
        if (thread.isAlive()) {
            killThread(thread); // do not use anything from the thread anymore,objects may be damaged!
            throwRuntimeException("Timeout",null);
        } else {
            Exception exceptionOccurredInThread = thread.getException();
            if (exceptionOccurredInThread != null) {
                throwRuntimeException("Exception",exceptionOccurredInThread);
            } else {
                result = thread.getResult();
            }
        }
        return result;
    }

    private void throwRuntimeException(String situation,Exception e) {
        throw new RuntimeException(situation + " occured while applying pattern /" + regularExpression + "/ to input '"
                + stringToMatch + " after " + timeoutMillis + "ms!",e);
    }

    /**
     * This method uses {@link Thread#stop()} to kill a thread that is running wild. Although it is acknowledged that
     * {@link Thread#stop()} is inherently unsafe,the assumption is that the thread to kill does not hold any monitors on or
     * even references to objects referenced by the rest of the JVM,so it is acceptable to do this.
     * 
     * After calling this method nothing from the thread should be used anymore!
     * 
     * @param thread Thread to stop
     */
    @SuppressWarnings("deprecation")
    private static void killThread(CallableThread<Boolean> thread) {
        thread.stop();
    }

    private static class CallableThread<V> extends Thread {

        private final Callable<V> callable;

        private V result = null;

        private Exception exception = null;

        public CallableThread(Callable<V> callable) {
            this.callable = callable;
        }

        @Override
        public void run() {
            try {
                V result = compute();
                setResult(result);
            } catch (Exception e) {
                exception = e;
            } catch (ThreadDeath e) {
                cleanup();
            }
        }

        private V compute() throws Exception {
            return callable.call();
        }

        private synchronized void cleanup() {
            result = null;
        }

        private synchronized void setResult(V result) {
            this.result = result;
        }

        public synchronized V getResult() {
            return result;
        }

        public synchronized Exception getException() {
            return exception;
        }

    }

}

编辑：

感谢dawce指出我this solution我已经能够解决我原来的问题,而无需额外的线程.我在那里发布了代码.感谢所有回复的人.