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Java run linux(raspbian) command(omxplayer) and get output

I create a program as below to execute a linux (raspbian) command: "omxplayer".
But I don't know why I cannot get output from omxplayer as the time I type it into command line and hit Enter.But the output only show at the end of the video.
So I want to get the output immediately after I type "omxplayer [video_name]" and hit "Enter" in my program.
Just like the command line (terminal) work when I type directly into it in linux.
This is my code:
public class testprog {
public static void main(String args[]) throws IOException {
String in = "";
while(in!="exit")
{
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
in = reader.readLine();
runCommand(in);
}
}
public static void runCommand(String command)
{
String s;
Process p;
try {
System.out.println("run command " + command);
p = Runtime.getRuntime().exec(new String[]{"bash", "-c",command});
MyInputStreamReader reader1 = new MyInputStreamReader(p.getInputStream());
reader1.setTag("in");
reader1.start();
MyInputStreamReader reader2 = new MyInputStreamReader(p.getErrorStream());
reader2.setTag("in");
reader2.start();
p.waitFor();
System.out.println ("exit: " + p.exitValue());
p.destroy();
} catch (Exception e) {}
}
}
class MyInputStreamReader extends Thread{
boolean isStop = false;
ReadEventHandler handler;
String tag;
InputStream in;
public MyInputStreamReader(InputStream in)
{
this.in = in;
}
public void setHandler(ReadEventHandler handler) {
this.handler = handler;
}
public void setTag(String tag)
{
this.tag = tag;
}
public void run()
{
byte[] buff = new byte[8192];
while (true) {
//String line;
try {
int len = in.read(buff);
if (len == -1)
{
return;
}
String line = new String(buff, 0, len);
if (handler!=null)
handler.onReceived(line);
System.out.println(tag +" " + line);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public void dispose()
{
this.isStop = true;
}
public interface ReadEventHandler
{
void onReceived(String line);
}
}
Any response is highly appreciated. Thanks

Did you checked this?
http://javedmandary.blogspot.com/2014/01/firing-up-raspberry-pi-omxplayer-using.html
I guess there is the code you're looking for.

ProcessBuilder command argument

(Sorry for my english I'm french) I'm creating a tiny Java IDE for my school project, but I'm facing a problem with running classes under Linux (I'm using Debian 7.3), no problem with Win 8.1
I'm using ProcessBuilder class to execute the java bin with some arguments, wich are args and projectOut
args = the class we want to run
projectOut = the absolute project path+"/out"
package com.esgi.honeycode;
import java.io.*;
import java.util.Scanner;
public class CustomRun {
public static void run(String args, final String projectOut) throws IOException {
System.out.flush();
if (args != null && projectOut != null) {
//SEPARATOR is a const for the file separator
ProcessBuilder builder = new ProcessBuilder("java", "-classpath", "\"" + System.getProperty("java.class.path") + System.getProperty("path.separator") + projectOut + PropertiesShared.SEPARATOR + "out\"", args);
System.out.println(builder.command());
builder.redirectErrorStream(true);
final Process process = builder.start();
Thread outThread = new Thread()
{
#Override
public void run() {
try {
String line;
try (BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()))) {
while ((line = reader.readLine()) != null) {
System.out.println(line);
}
}
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
};
Thread inThread = new Thread() {
#Override
public void run() {
Scanner s = new Scanner(System.in);
//Need to control in before !!
while (true) {
String input = s.nextLine();
try (PrintWriter pw = new PrintWriter(new OutputStreamWriter(process.getOutputStream()))) {
pw.write(input);
pw.flush();
}
}
}
};
outThread.start();
inThread.start();
}
}
}
Testing with a simple class :
public class MyClass{
public static void main(String[] args)
{
System.out.println("TESTESTE");
}
}
the class is stored in : /home/m3te0r/HoneyCodeProjects/untitledaaa/out
And if I try to run the class, I get this output, with the command print :
[java, -classpath, "/home/m3te0r/Bureau/HoneyCode.jar:/home/m3te0r/HoneyCodeProjects/untitledaaa/out", MyClass]
Error: Could not find or load main class MyClass
Like I said, there is no problem under Win 8.1 and it also works when I run the same command in a terminal.
EDIT FOR THE ANSWER ():
Ok, so I figured out what was wrong.
I just removed the escaped double quotes fot the classpath and it worked.
I was thinking there would be a problem with spaced dir names or files, but there is not.
ProcessBuilder builder = new ProcessBuilder("java", "-classpath", System.getProperty("java.class.path") + System.getProperty("path.separator") + projectOut + PropertiesShared.SEPARATOR + "out", args);

Reading output from java.lang.Process - There is nothing to read

I'm trying to execute terminal command in linux trough Java and i cant get any input from inputStream.
This is my code
ProcessBuilder build = new ProcessBuilder("/usr/bin/xterm", "find /home");
Process pr = null;
BufferedReader buf;
try {
build.redirectErrorStream(true);
pr = build.start();
buf = new BufferedReader(new InputStreamReader( pr.getInputStream()));
String line = buf.readLine();
pr.waitFor();
while (true) {
System.out.println(line + "sadasdas");
line = buf.readLine();
}
} catch (Exception e) {
e.printStackTrace();
}
Process is executed and immediately terminal closes, and no output is catched and printed. On the other hand if i will compose an unknown command i get all the lines with tips how to use commands. Same problem i had with windows cmd. I was trying to use getRuntime.exec(cmd) method but the end is the same.
I've also tried to created separate threads for process and reader which looks like this
public class kurdee
{
public static Thread thread;
public kurdee()
{
List cmd = new LinkedList();
cmd.add(new String("/usr/bin/xterm"));
cmd.add(new String("find"));
thisProc thispr = new thisProc(cmd);
this.thread = new Thread(thispr);
thread.start();
reader rd = new reader(thispr.proc);
Thread thread1 = new Thread(rd);
thread1.start();}
public static void main(String args[])
{
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
kurdee kurd = new kurdee();
}
});
}
}
class reader implements Runnable
{
private BufferedReader buf;
private Process proc;
public reader(Process proc)
{
this.proc=proc;
this.buf = new BufferedReader(new InputStreamReader(proc.getInputStream()));
}
public void run()
{
String line="";
System.out.println("Thread is alive");
try{
//Thread.sleep(1000);
line = buf.readLine();
}catch(Exception ex){System.out.println(ex + " before first while started");}
while(kurdee.thread.isAlive())
{
System.out.println("Thread is alive");
while(line!=null)
{
try{
//System.out.println(proc.exitValue());
System.out.println(line + " asd");
line=buf.readLine();
}catch(Exception e){System.out.println(e + " Inner while loop");}
}
}
}
}
class thisProc implements Runnable
{
private ProcessBuilder build;
public static Process proc=null;
public thisProc(List<String> args)
{
this.build = new ProcessBuilder(args);
build.redirectErrorStream(true);
try{
this.proc = build.start();
}catch(Exception ex){System.out.println(ex + " proc class");}
}
public void run()
{
try{
proc.waitFor();
}catch(Exception ex){System.out.println(ex + " proc class");}
}
}
But with any combination of invoking threads etc i make there is still nothing to read.
I'm trying to use command "find /home -xdev -samefile file" to get all hard links to file so maybe there is an easier way.

xterm is not the way to execute processes in unix, it is not a shell. a shell is something like "/bin/sh". however, "find" is a normal unix executable, so you should just execute that directly, e.g. new ProcessBuilder("find", "/home"). and yes, you should always process the streams on separate threads, as recommended by this article.

First, don't try to execute the command with xterm, that's pointless; just do it directly. Secondly, be careful when you compose your array of command strings to put one word into each string; passing, for example "find /home" as a single string among many to ProcessBuilder is going to error out.

How do I stop a process controlled by a thread?

I have a Java application which launches another application with some parameters. The Java should be able to continue meanwhile and kill the other application after user input.
Reading up on this I found out I should use Thread.Interupt() because Thread.Stop() is deprecated.
On your thread it would throw a InterruptedExection. So what I have is:
public class ProcessExecutor extends Object implements Runnable {
private volatile int id;
private String message;
private Process proc = null;
public ProcessExecutor(int id, String message) {
this.id = id;
this.message = message;
}
public int GetId() {
return id;
}
public void run() {
try {
String[] cmd = new String[4];
cmd[0] = "path to some app";
cmd[1] = id;
cmd[2] = message;
Runtime rt = Runtime.getRuntime();
proc = rt.exec(cmd);
BufferedReader input = new BufferedReader(new InputStreamReader(proc.getInputStream()));
String line=null;
while ((line=input.readLine()) != null) {
System.out.println("ProcessExecutor: " + line);
}
int exitVal = proc.waitFor();
System.out.println("ProcessExecutor: Exited with error code " + exitVal);
} catch(InterruptedException ex) {
System.out.println("ProcessExecutor: stopping");
if (proc != null) {
proc.destroy();
proc = null;
}
} catch(Exception e) {
System.out.println("ProcessExecutor: exception: " + e.toString());
e.printStackTrace();
}
}
}
Which is handled by:
private List<Thread> activeProccesses = new ArrayList<Thread>();
public void StartProcess(int id, String message) {
System.out.println("StartProcess: id=" + id + ", message='" + message + "'");
StopAllProcesses();
ProcessExecutor proc = new ProcessExecutor(id, message);
Thread procThread = new Thread(proc);
activeProccesses.add(procThread);
procThread.start();
}
public void StopAllProcesses() {
System.out.println("Stopping all processes");
Iterator<Thread> it = activeProccesses.iterator();
while (it.hasNext()) {
Thread procThread = it.next();
if (procThread.isAlive()) {
procThread.interrupt();
}
it.remove();
}
System.out.println("Stopping all processes: done");
}
How ever the procThread.interrupt() gets executed but the catch(InterruptedException ex) never hits.
Why is this and how can I fix this?
Edit: The conclusion
Turned out the Thread was blocked by the input.readLine() inorder to stop that I had to directly stop the Process which then unblocked the input.readLine().
public class ProcessExecutor extends Thread {
private volatile int id;
private String message;
private volatile Process proc = null;
public ProcessExecutor(int id, String message) {
this.id = id;
this.message = message;
}
public int GetId() {
return id;
}
public void StopProc() {
if (proc != null) {
proc.destroy();
}
}
public void run() {
try {
String[] cmd = new String[4];
cmd[0] = "path to some app";
cmd[1] = id;
cmd[2] = message;
Runtime rt = Runtime.getRuntime();
proc = rt.exec(cmd);
BufferedReader input = new BufferedReader(new InputStreamReader(proc.getInputStream()));
String line=null;
while ((line=input.readLine()) != null) {
System.out.println("ProcessExecutor: " + line);
}
int exitVal = proc.waitFor();
proc = null;
System.out.println("ProcessExecutor: Exited with error code " + exitVal);
} catch(Exception e) {
System.out.println("ProcessExecutor: exception: " + e.toString());
StopProc();
}
}
}
private List<ProcessExecutor> activeProccesses = new ArrayList<ProcessExecutor>();
public void StartProcess(int id, String message) {
System.out.println("StartProcess: id=" + id + ", message='" + message + "'");
StopAllProcesses();
ProcessExecutor proc = new ProcessExecutor(id, message);
activeProccesses.add(proc);
proc.start();
}
public void StopAllProcesses() {
System.out.println("Stopping all processes");
Iterator<ProcessExecutor> it = activeProccesses.iterator();
while (it.hasNext()) {
ProcessExecutor proc = it.next();
proc.StopProc();
it.remove();
}
System.out.println("Stopping all processes: done");
}

As I said in my comment. I think the only way to interrupt a thread blocked reading a line is to kill the process from which the thread reads. Just as the only solution to interrupt a thread blocked reading on a socket is to close the socket.
Add a method to your thread that destroys the process.

You have to explicitly check for the interrupted condition in your ProcessExecutor; an InterruptedException will not be thrown automatically. Something like this:
public class ProcessExecutor extends Object implements Runnable {
public void run() {
try {
//other code....
while ((line=input.readLine()) != null) {
System.out.println("ProcessExecutor: " + line);
if (Thread.interrupted()) {
// We've been interrupted!
throw new InterruptedException("....");
}
}
} catch(InterruptedException ex) {
System.out.println("ProcessExecutor: stopping");
}
See http://docs.oracle.com/javase/tutorial/essential/concurrency/interrupt.html for more details.

Interrupting threads only works if they are in specific states, usually it's done during wait() calls that are done when not actively processing data.
If you want the thread to die in between readLine() calls you can check interrupted() in the while check instead of using a try-catch.
Edit: the best way to solve your problem would be
while (true)
{
if (input.ready())
{
line = input.readLine();
System.out.println("ProcessExecutor: " + line);
} else {
try { Thread.sleep(100); } // time to wait in ms
catch (InterruptedException ie) { break; }
}
}
Since ready() actually checks for a single character you should use successive read() instead of readLine(), but if you write on the stream a line at a time there should be no difference this way. The time to wait for is clearly arbitrary.

I would suggest more graceful way to stop a thread. In the run method, you have following code
while ((line=input.readLine()) != null) {
System.out.println("ProcessExecutor: " + line);
}
in ProcessExecutor, add a boolean field accompanied by its getter and setter.
private Boolean stop = false;
and check the same flag in while condition.
while (((line=input.readLine()) != null) && !stop) {
System.out.println("ProcessExecutor: " + line);
}
in StopAllProcesses() method, set stop=true on ProcessExecutor instances . this will result into run() method returning and gracefully stopping the thread.

How to find and kill running Win-Processes from within Java?

I need a Java way to find a running Win process from which I know to name of the executable. I want to look whether it is running right now and I need a way to kill the process if I found it.

private static final String TASKLIST = "tasklist";
private static final String KILL = "taskkill /F /IM ";
public static boolean isProcessRunning(String serviceName) throws Exception {
Process p = Runtime.getRuntime().exec(TASKLIST);
BufferedReader reader = new BufferedReader(new InputStreamReader(
p.getInputStream()));
String line;
while ((line = reader.readLine()) != null) {
System.out.println(line);
if (line.contains(serviceName)) {
return true;
}
}
return false;
}
public static void killProcess(String serviceName) throws Exception {
Runtime.getRuntime().exec(KILL + serviceName);
}
EXAMPLE:
public static void main(String args[]) throws Exception {
String processName = "WINWORD.EXE";
//System.out.print(isProcessRunning(processName));
if (isProcessRunning(processName)) {
killProcess(processName);
}
}

You can use command line windows tools tasklist and taskkill and call them from Java using Runtime.exec().

Here's a groovy way of doing it:
final Process jpsProcess = "cmd /c jps".execute()
final BufferedReader reader = new BufferedReader(new InputStreamReader(jpsProcess.getInputStream()));
def jarFileName = "FileName.jar"
def processId = null
reader.eachLine {
if (it.contains(jarFileName)) {
def args = it.split(" ")
if (processId != null) {
throw new IllegalStateException("Multiple processes found executing ${jarFileName} ids: ${processId} and ${args[0]}")
} else {
processId = args[0]
}
}
}
if (processId != null) {
def killCommand = "cmd /c TASKKILL /F /PID ${processId}"
def killProcess = killCommand.execute()
def stdout = new StringBuilder()
def stderr = new StringBuilder()
killProcess.consumeProcessOutput(stdout, stderr)
println(killCommand)
def errorOutput = stderr.toString()
if (!errorOutput.empty) {
println(errorOutput)
}
def stdOutput = stdout.toString()
if (!stdOutput.empty) {
println(stdOutput)
}
killProcess.waitFor()
} else {
System.err.println("Could not find process for jar ${jarFileName}")
}

There is a little API providing the desired functionality:
https://github.com/kohsuke/winp
Windows Process Library

You could use a command line tool for killing processes like SysInternals PsKill and SysInternals PsList.
You could also use the build-in tasklist.exe and taskkill.exe, but those are only available on Windows XP Professional and later (not in the Home Edition).
Use java.lang.Runtime.exec to execute the program.

Use the following class to kill a Windows process (if it is running). I'm using the force command line argument /F to make sure that the process specified by the /IM argument will be terminated.
import java.io.BufferedReader;
import java.io.InputStreamReader;
public class WindowsProcess
{
private String processName;
public WindowsProcess(String processName)
{
this.processName = processName;
}
public void kill() throws Exception
{
if (isRunning())
{
getRuntime().exec("taskkill /F /IM " + processName);
}
}
private boolean isRunning() throws Exception
{
Process listTasksProcess = getRuntime().exec("tasklist");
BufferedReader tasksListReader = new BufferedReader(
new InputStreamReader(listTasksProcess.getInputStream()));
String tasksLine;
while ((tasksLine = tasksListReader.readLine()) != null)
{
if (tasksLine.contains(processName))
{
return true;
}
}
return false;
}
private Runtime getRuntime()
{
return Runtime.getRuntime();
}
}

You will have to call some native code, since IMHO there is no library that does it. Since JNI is cumbersome and hard you might try to use JNA (Java Native Access). https://jna.dev.java.net/

small change in answer written by Super kakes
private static final String KILL = "taskkill /IMF ";
Changed to ..
private static final String KILL = "taskkill /IM ";
/IMF option doesnot work .it does not kill notepad..while /IM option actually works