Question

嗨我试图阻止一个线程并阻止FFmpeg继续在bachground中。因此，当用户单击取消按钮时，它会停止线程并停止FFmpeg我将首先显示我的类MashRocks，该按钮调用方法，所以我想这就是我应该显示的所有内容。

package my.mashformcnts;
import java.io.IOException;
import java.util.Scanner;
import java.util.regex.Pattern;


/**
 *
 * @author brett
 */
public class MashRocks {

    public static Thread startThread(MashFormCnts mashFormCnts) throws IOException {
        ProcessBuilder pb = new ProcessBuilder("ffmpeg", "-i", "C:\\Users\\brett\\Documents\\Telegraph_Road.mp4", "C:\\Users\\brett\\Documents\\out.mp4");
        final Process p = pb.start();
        // create a new thread to get progress from ffmpeg command , override  
        // it's run method, and start it!  
        Thread t = new Thread() {
            @Override
            public void run() {
                Scanner sc = new Scanner(p.getErrorStream());
                // Find duration  
                Pattern durPattern = Pattern.compile("(?<=Duration: )[^,]*");
                String dur = sc.findWithinHorizon(durPattern, 0);
                if (dur == null) {
                    throw new RuntimeException("Could not parse duration.");
                }
                String[] hms = dur.split(":");
                double totalSecs = Integer.parseInt(hms[0]) * 3600 + Integer.parseInt(hms[1]) * 60 + Double.parseDouble(hms[2]);
                System.out.println("Total duration: " + totalSecs + " seconds.");
                // Find time as long as possible.  
                Pattern timePattern = Pattern.compile("(?<=time=)[\\d:.]*");
                String match;
                String[] matchSplit;
                //MashForm pgbar = new MashForm();
                while (null != (match = sc.findWithinHorizon(timePattern, 0))) {
                    matchSplit = match.split(":");
                    double progress = (Integer.parseInt(matchSplit[0]) * 3600 + Integer.parseInt(matchSplit[1]) * 60 + Double.parseDouble(matchSplit[2])) / totalSecs;
                    int prog = (int) (progress * 100);
                    mashFormCunts.setbar(prog);
                }
            }
        };
       t.start();
       return t;
    }
   //This works but is it correct??
   public synchronized static Thread stop(Thread t){
       Runtime.getRuntime().exec("taskkill /F /IM ffmpeg.exe");  
        t = null;
      //t.interrupt();
          //im not sure what else to do?


   }
}

同样在我的表单中，这个代码我用来获取Thread并将其发送到方法

 private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {                                         
        // TODO add your handling code here:
        Thread t = Thread.currentThread();
        System.out.print(t);
        MashRocks.stop(t);
    }

Answer 1

你是对的，有更好的方法。您应该将Process值存储在某处，并使用Process.destroyForcibly（）来终止它。根据您发布的代码，您可能希望将Thread子类化，这样您就可以存储可以轻松返回的Process。

启动时，您还需要存储对自定义Thread对象的引用。如果一次只能有一个，则可以使用单例来存储单个实例。如果可能有多个，您将需要创建活动线程的列表或注册表。

试图停止Thread并在后台停止ffmpeg

1 个答案: