简单的异步I / O：许多线程，一个文件(Simple asynchronous I/O: many threads, one file)

 我有一个科学的应用程序，我通常与xargs并行运行，但这个方案会导致重复的JVM启动成本，并忽略缓存的文件I / O和JIT编译器。 我已经调整了代码来使用线程池，但是我一直在保存我的输出。 
 
 程序（即新程序的一个线程）读取两个文件，执行一些处理，然后将结果打印到标准输出。 目前，我已经通过让每个线程将其结果字符串添加到BlockingQueue来处理输出。 另一个线程从队列中取出并写入文件，只要布尔标志为真即可。 然后我awaitTermination并将标志设置为false，触发文件关闭并退出程序。 
 
 我的解决方案似乎有点杂乱; 什么是最简单和最好的方式来实现这一目标？ 我应该如何将来自多个线程的主要结果数据写入单个文件？ 
 
 例如，如果答案是广泛适用的方法，则答案不一定是Java特定的。 
 
 更新 
 
 我正在使用“STOP”作为毒丸。 
 
while (true) {
    String line = queue.take();
    if (line.equals("STOP")) {
        break;
    } else {
        output.write(line);
    }
}
output.close();
 
 我手动启动队列消耗线程，然后将作业添加到线程池，等待作业完成，最后中毒队列并加入使用者线程。 

I have a scientific application which I usually run in parallel with xargs, but this scheme incurs repeated JVM start costs and neglects cached file I/O and the JIT compiler. I've already adapted the code to use a thread pool, but I'm stuck on how to save my output.
 
The program (i.e. one thread of the new program) reads two files, does some processing and then prints the result to standard output. Currently, I've dealt with output by having each thread add its result string to a BlockingQueue. Another thread takes from the queue and writes to a file, as long as a Boolean flag is true. Then I awaitTermination and set the flag to false, triggering the file to close and the program to exit.
 
My solution seems a little kludgey; what is the simplest and best way to accomplish this? How should I write primary result data from many threads to a single file?
 
The answer doesn't need to be Java-specific if it is, for example, a broadly applicable method.
 
Update
 
I'm using "STOP" as the poison pill.
 
while (true) {
    String line = queue.take();
    if (line.equals("STOP")) {
        break;
    } else {
        output.write(line);
    }
}
output.close();
 
I manually start the queue-consuming thread, then add the jobs to the thread pool, wait for the jobs to finish and finally poison the queue and join the consumer thread.

原文：https://stackoverflow.com/questions/6637357