java - Android连续获取进程输出

Question

我有一个我启动的 android 进程。这是一个 getevent 命令。这(当在控制台中运行时)给出了连续的事件发生。我希望在 Android 应用程序中收集这些。我目前这样做的方式将有效地收集“一次性”过程输出，但我似乎无法找到一种方法来存储来自 getevent 方法的连续结果。

我目前的代码如下。它适用于“ls”之类的东西，但不适用于“getevent”之类的连续流。

try {
            Process chmod = Runtime.getRuntime().exec("getevent -lt /dev/input/event1");

            BufferedReader reader = new BufferedReader(new InputStreamReader(chmod.getInputStream()));
            int read;
            char[] buffer = new char[4096];
            StringBuffer output = new StringBuffer();
            while ((read = reader.read(buffer)) > 0) {
                output.append(buffer, 0, read);
            }
            reader.close();
            chmod.waitFor();
            String outputString =  output.toString();
            Log.d("output", outputString);
        } catch (IOException e) {
            throw new RuntimeException(e);
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        }

Answer 1

我遇到了同样的问题。这是我解决它的方法。

首先，我创建了一个 TimerTask 来记录/读取 logcat 或 getevent 的 BufferReader 中的连续输出。 TimerTask 创建新线程，它在后台运行并且不会干扰或阻止服务类中的其他 UI 处理程序。所以我相信那样更安全。

然后我在 onCreate() 方法中从 Service 类启动了 TimerTask。

一件事是我的设备被 root，所以我从“su” session 开始。我相信“sh” session 也适用于非根设备。

服务类:

public class ServiceClassPhone extends Service {
....

private GetEventRecorder getEventRecorder;

@Override
public void onCreate() {

....

getEventRecorder= new GetEventRecorder();
getEventRecorder.start();
// (if there is any) postDelay other UI handlers in service
}

和 GetEventRecorder 类:

public class GetEventRecorder {


....
private static Logger mLogger = new Logger();

private GetEventRecorder mRecorder = null;
Timer timer;

// active su session
private Process mProcess;
// Byte Writer
private OutputStream mStdIn;
private DataOutputStream outputStream;
private BufferedReader br;


{
    try {
        mProcess = Runtime.getRuntime().exec("su");

        outputStream = new DataOutputStream(mProcess.getOutputStream());
        String comm1 = "getevent -l";
        String comm2 = "logcat -c";
        String close = "^C";
        String newLine= "\n";

        outputStream.writeBytes(comm1);
        outputStream.writeBytes(newLine);


    } catch (IOException e) {
        Log.d(TAG, "Could not spawn su process");
        e.printStackTrace();
    }
}


public void start()  {

        try {

            timer = new Timer();
            timer.scheduleAtFixedRate(new GetEventRecorder.RecorderTask(), 0, 1000);
        } catch (Exception e) {
            Log.d(TAG, "Exception: " + e);
        }

}

public void stop() {
    if (mRecorder != null) {
        mRecorder.stop();
        mRecorder = null;
        timer.cancel();
    }
}



public void logGetEventData(){
    ....

}

}


    private class RecorderTask extends TimerTask {


    public RecorderTask() {}


    @Override
    public void run() {

        try {

            String comm1 = "getevent -l";
            String comm2 = "logcat -c";
            String close = "^C";
            byte[] newLine = "\n".getBytes();

            outputStream.writeBytes(close);
            outputStream.flush();


            br = new BufferedReader(new InputStreamReader(mProcess.getInputStream()));
            boolean cont=true;
            String line;
            Log.d(TAG,"geteventLogs BufferedReader for continuous getevent reading... " );
            if (br!=null ) {
                Log.d(TAG,"geteventLogs BufferedReader is not null checking for readiness... ");
                if (br.ready()) {
                    Log.d(TAG, "BufferedReader for getevent is not null and ready");


                    String separator = System.getProperty("line.separator");
                    while ((line = br.readLine()) != null && line.contains("event0:")
                            && !line.contains("BufferedReader") ) {
                            ...
                            logGetEventData();

        }catch (Exception e) {
            if (DBG) Log.d(TAG, "getevent recorder error: " + e);
        }
    }
}


}