CLI进程的线程池(ThreadPool of CLI Processes)

我需要通过从Java标准输入传递消息，CLI PHP程序。 我想保持在一个池中运行约20 PHP的过程，例如，当我传递消息到池中时，它发送的每个消息，以一个单独的线程，保持消息队列被递送。 我想这些PHP程序尽可能长时间维持生命，带来了一个新的，如果一人死亡。 我看着一个静态线程池这样做，但它似乎更专为执行，只是死任务。 我怎么能做到这一点，一个简单的界面来传递消息到池？ 请问我要实现自己的自定义“线程池”？

Answer 1:

我提供一些代码，使这是我认为这将让事情更清晰。 基本上你需要保持一个池的过程中物体周围。 体贴是每个流程都有，你需要以某种方式来管理输入，输出和错误流。 在我的例子我只是重定向错误并输出到主流程控制台。 您可以根据需要设置回调和处理程序来获得PHP程序的输出。 如果你是刚刚处理任务，并不在乎什么PHP接着说保留原样或重定向到一个文件中。

我使用的Apache的共享池库中ObjectPool的。 无需重新发明之一。

你必须运行你的PHP程序20个进程池。 仅凭这一点不会得到你所需要的。 您可能要处理针对这些过程的全部20个任务“在同一时间。” 所以，你还需要一个线程池，将拉过程从ObjectPool的。

您还需要了解的是，如果你杀死，或CTRL-C您的Java程序的init过程将接管你的PHP程序，他们将只是坐在那里。 你可能想保留日志的PHP的所有PID的进程你产卵，然后清除它们，如果你重新运行Java程序。

public class StackOverflow_10037379 {

    private static Logger sLogger = Logger.getLogger(StackOverflow_10037379.class.getName());

    public static class CLIPoolableObjectFactory extends BasePoolableObjectFactory<Process> {

        private String mProcessToRun;

        public CLIPoolableObjectFactory(String processToRun) {
            mProcessToRun = processToRun;
        }

        @Override
        public Process makeObject() throws Exception {
            ProcessBuilder builder = new ProcessBuilder();
            builder.redirectError(Redirect.INHERIT);
            // I am being lazy, but really the InputStream is where
            // you can get any output of the PHP Process. This setting
            // will make it output to the current processes console.
            builder.redirectOutput(Redirect.INHERIT);
            builder.redirectInput(Redirect.PIPE);
            builder.command(mProcessToRun);
            return builder.start();
        }

        @Override
        public boolean validateObject(Process process) {
            try {
                process.exitValue();
                return false;
            } catch (IllegalThreadStateException ex) {
                return true;
            }
        }

        @Override
        public void destroyObject(Process process) throws Exception {
            // If PHP has a way to stop it, do that instead of destroy
            process.destroy();
        }

        @Override
        public void passivateObject(Process process) throws Exception {
            // Should really try to read from the InputStream of the Process
            // to prevent lock-ups if Rediret.INHERIT is not used.
        }
    }

    public static class CLIWorkItem implements Runnable {

        private ObjectPool<Process> mPool;
        private String mWork;

        public CLIWorkItem(ObjectPool<Process> pool, String work) {
            mPool = pool;
            mWork = work;
        }

        @Override
        public void run() {
            Process workProcess = null;
            try {
                workProcess = mPool.borrowObject();
                OutputStream os = workProcess.getOutputStream();
                os.write(mWork.getBytes(Charset.forName("UTF-8")));
                os.flush();
                // Because of the INHERIT rule with the output stream
                // the console stream overwrites itself. REMOVE THIS in production.
                Thread.sleep(100);
            } catch (Exception ex) {
                sLogger.log(Level.SEVERE, null, ex);
            } finally {
                if (workProcess != null) {
                    try {
                        // Seriously.. so many exceptions.
                        mPool.returnObject(workProcess);
                    } catch (Exception ex) {
                        sLogger.log(Level.SEVERE, null, ex);
                    }
                }
            }
        }
    }

    public static void main(String[] args) throws Exception {

        // Change the 5 to 20 in your case. 
        // Also change mock_php.exe to /usr/bin/php or wherever.
        ObjectPool<Process> pool =
                new GenericObjectPool<>(
                new CLIPoolableObjectFactory("mock_php.exe"), 5);         

        // This will only allow you to queue 100 work items at a time. I would suspect
        // that if you only want 20 PHP processes running at a time and this queue
        // filled up you'll need to implement some other strategy as you are doing
        // more work than PHP can keep up with. You'll need to block at some point
        // or throw work away.
        BlockingQueue<Runnable> queue = 
            new ArrayBlockingQueue<>(100, true);

        ThreadPoolExecutor executor = 
            new ThreadPoolExecutor(20, 20, 1, TimeUnit.HOURS, queue);

        // print some stuff out.
        executor.execute(new CLIWorkItem(pool, "Message 1\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 2\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 3\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 4\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 5\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 6\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 7\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 8\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 9\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 10\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 11\r\n"));

        executor.shutdown();
        executor.awaitTermination(4000, TimeUnit.HOURS);

        pool.close();        
    }
}

程序运行的输出：

12172 - Message 2
10568 - Message 1
4804 - Message 3
11916 - Message 4
11116 - Message 5
12172 - Message 6
4804 - Message 7
10568 - Message 8
11916 - Message 9
11116 - Message 10
12172 - Message 11

的C ++代码程序只是输出什么输入：

#include <windows.h>
#include <iostream>
#include <string>

int main(int argc, char* argv[])
{
    DWORD pid = GetCurrentProcessId();
    std::string line;
    while (true) {      
        std::getline (std::cin, line);
        std::cout << pid << " - " << line << std::endl;
    }

    return 0;
}

更新

抱歉耽搁了。 这里是一个JDK版本6兴趣的人。 你必须运行一个单独的线程从过程的InputStream读入所有的输入。 我给自己定的代码了产卵沿侧一个新的线程每一个新的进程。 该线程总是从过程只要它是活的阅读。 而不是直接输出到文件中我把它使得它使用的日志框架。 这样，你可以设置一个日志记录配置去一个文件，滚动，去安慰等而不会被硬编码到一个文件中。

你会注意到我只启动一个gobbler之。因为即使一个进程有输出和错误的每个过程。 我stderr重定向到标准输出，只是为了让事情变得更容易。 显然，只有JDK6支持这种类型的重定向。

public class StackOverflow_10037379_jdk6 {

    private static Logger sLogger = Logger.getLogger(StackOverflow_10037379_jdk6.class.getName());

    // Shamelessy taken from Google and modified. 
    // I don't know who the original Author is.
    public static class StreamGobbler extends Thread {

        InputStream is;
        Logger logger;
        Level level;

        StreamGobbler(String logName, Level level, InputStream is) {
            this.is = is;
            this.logger = Logger.getLogger(logName);
            this.level = level;
        }

        public void run() {
            try {
                InputStreamReader isr = new InputStreamReader(is);
                BufferedReader br = new BufferedReader(isr);
                String line = null;
                while ((line = br.readLine()) != null) {
                    logger.log(level, line);
                }
            } catch (IOException ex) {
                logger.log(Level.SEVERE, "Failed to read from Process.", ex);
            }
            logger.log(
                    Level.INFO, 
                    String.format("Exiting Gobbler for %s.", logger.getName()));
        }
    }

    public static class CLIPoolableObjectFactory extends BasePoolableObjectFactory<Process> {

        private String mProcessToRun;

        public CLIPoolableObjectFactory(String processToRun) {
            mProcessToRun = processToRun;
        }

        @Override
        public Process makeObject() throws Exception {
            ProcessBuilder builder = new ProcessBuilder();
            builder.redirectErrorStream(true);
            builder.command(mProcessToRun);
            Process process = builder.start();
            StreamGobbler loggingGobbler =
                    new StreamGobbler(
                    String.format("process.%s", process.hashCode()),
                    Level.INFO,
                    process.getInputStream());
            loggingGobbler.start();
            return process;
        }

        @Override
        public boolean validateObject(Process process) {
            try {
                process.exitValue();
                return false;
            } catch (IllegalThreadStateException ex) {
                return true;
            }
        }

        @Override
        public void destroyObject(Process process) throws Exception {
            // If PHP has a way to stop it, do that instead of destroy
            process.destroy();
        }

        @Override
        public void passivateObject(Process process) throws Exception {
            // Should really try to read from the InputStream of the Process
            // to prevent lock-ups if Rediret.INHERIT is not used.
        }
    }

    public static class CLIWorkItem implements Runnable {

        private ObjectPool<Process> mPool;
        private String mWork;

        public CLIWorkItem(ObjectPool<Process> pool, String work) {
            mPool = pool;
            mWork = work;
        }

        @Override
        public void run() {
            Process workProcess = null;
            try {
                workProcess = mPool.borrowObject();
                OutputStream os = workProcess.getOutputStream();
                os.write(mWork.getBytes(Charset.forName("UTF-8")));
                os.flush();
                // Because of the INHERIT rule with the output stream
                // the console stream overwrites itself. REMOVE THIS in production.
                Thread.sleep(100);
            } catch (Exception ex) {
                sLogger.log(Level.SEVERE, null, ex);
            } finally {
                if (workProcess != null) {
                    try {
                        // Seriously.. so many exceptions.
                        mPool.returnObject(workProcess);
                    } catch (Exception ex) {
                        sLogger.log(Level.SEVERE, null, ex);
                    }
                }
            }
        }
    }

    public static void main(String[] args) throws Exception {

        // Change the 5 to 20 in your case. 
        ObjectPool<Process> pool =
                new GenericObjectPool<Process>(
                new CLIPoolableObjectFactory("mock_php.exe"), 5);

        BlockingQueue<Runnable> queue = new ArrayBlockingQueue<Runnable>(100, true);

        ThreadPoolExecutor executor = new ThreadPoolExecutor(20, 20, 1, TimeUnit.HOURS, queue);

        // print some stuff out.
        executor.execute(new CLIWorkItem(pool, "Message 1\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 2\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 3\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 4\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 5\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 6\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 7\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 8\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 9\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 10\r\n"));
        executor.execute(new CLIWorkItem(pool, "Message 11\r\n"));

        executor.shutdown();
        executor.awaitTermination(4000, TimeUnit.HOURS);

        pool.close();
    }
}

产量

Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 9440 - Message 3
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 8776 - Message 2
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 6100 - Message 1
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 10096 - Message 4
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 8868 - Message 5
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 8868 - Message 8
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 6100 - Message 10
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 8776 - Message 9
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 10096 - Message 6
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 9440 - Message 7
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: 6100 - Message 11
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: Exiting Gobbler for process.295131993.
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: Exiting Gobbler for process.756434719.
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: Exiting Gobbler for process.332711452.
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: Exiting Gobbler for process.1981440623.
Apr 11, 2012 8:41:02 PM stackoverflow.StackOverflow_10037379_jdk6$StreamGobbler run
INFO: Exiting Gobbler for process.1043636732.

Answer 2:

这里最好的办法是使用了pcntl功能派生进程，但进程之间的通信是困难的。 我建议建立一个队列，你的进程可以读出，而不是试图将消息传递给命令行。

魔豆有，你可以用它来处理进程之间的消息传递几个PHP客户。

文章来源: ThreadPool of CLI Processes