Develop Reference

Running SoX from Processing/Java on Windows computer

This might be an easy one - but it's driving me nuts at this point. I'm trying to run SoX from Processing which on my mac computer is running smoothly and with no problems. I need to migrate the code to a windows 7 machine but can't get it to work for some reason. Talking to the terminal from processing works fine. I'm in the right folder (sketch data folder where SoX is also intalled) since I can run commands like "dir" etc. and get the right content printed - but as soon as I try to run sox.exe nothing happens (getting an exit value 1). Running sox.exe straight from the cmd terminal works fine. Here is a sample of what I'm trying to do:
void playBackYear (){
soxPlay = "cmd /c sox.exe year.wav -d";
println (soxPlay);
try {
File workingDir = new File(sketchPath("data"));
Process p=Runtime.getRuntime().exec(soxPlay, null, workingDir);
p.waitFor();
BufferedReader reader=new BufferedReader(
new InputStreamReader(p.getInputStream())
);
String line;
while ( (line = reader.readLine ()) != null)
{
println(line);
}
int exitVal = p.waitFor();
System.out.println("Exited with error code "+exitVal);
}
catch(IOException e1) {
System.err.println("Caught IOException: " + e1.getMessage());
System.out.println( "error 1" );
}
catch(InterruptedException e2) {
System.err.println("Caught IOException: " + e2.getMessage());
System.out.println( "error 2" );
}
}
So the questions is what am I doing wrong here?
Any help is appreciated.

I have written a small wrapper application that wraps sox binary in java. If you are interested in the full project, check it out on GitHub: sox java wrapper project
This is, how i have solved the problem:
private List<String> arguments = new ArrayList<String>();
// add sox arguments to this list above
public void execute() throws IOException {
File soxBinary = new File(soXBinaryPath);
if (!soxBinary.exists()) {
throw new FileNotFoundException("Sox binary is not available under the following path: " + soXBinaryPath);
}
arguments.add(0, soXBinaryPath);
logger.debug("Sox arguments: {}", arguments);
ProcessBuilder processBuilder = new ProcessBuilder(arguments);
processBuilder.redirectErrorStream(true);
Process process = null;
IOException errorDuringExecution = null;
try {
process = processBuilder.start();
BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
String line;
while ((line = reader.readLine()) != null) {
logger.debug(line);
}
} catch (IOException e) {
errorDuringExecution = e;
logger.error("Error while running Sox. {}", e.getMessage());
} finally {
arguments.clear();
if (process != null) {
process.destroy();
}
if (errorDuringExecution != null) {
throw errorDuringExecution;
}
}
}

How could I pass in commands into a terminal that is already running in java (linux)

I have been researching how to run a terminal command in java. I am doing this to make a program I can use to ssh into another pc (just as a project). How could I keep continuing putting commands in this terminal? If I run this I get a message to put in my password and if I do so it will print out what the messages the terminal spits out at the :
while((line = in.readLine()) != null){
System.out.println(line + "\n");
}
line, but a few seconds after that my program will stop working.
I currently have a GUI that is just a button and if I press the button it will run this code. Could someone help me to fix the issue of it stopping and give me information on how I could continue to put commands into the terminal? Thanks.
Process p = null;
String[] command = {"/bin/sh", "-c", "ssh 192.168.2.100"};
ProcessBuilder pb = new ProcessBuilder(command);
String line = null;
try {
term = pb.start();
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
InputStream is = p.getInputStream();
BufferedReader in = new BufferedReader(new InputStreamReader(is));
try {
while((line = in.readLine()) != null){
System.out.println(line + "\n");
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
in.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

You can not pass the argument to live JVM, But there is way in which you can modify the some of the parameters which done using JMX, with this you can connect to live JVM and send the parameters. which will be taken the effect immediately.
Hope that helps

How can I execute linux terminal command from java?

I want to automatically change the ip address of an Ubuntu 12.04 PC by a program fires at startup. For some certain reasons, I want to code it in Java.
Exactly the solution is written here:
Java - Execute a .SH file
But it does not work in my case. I could not manage to find why,essentially my case is a special case of so called thread, I try to run a sudo-command in linux with
public static void executeCommandLine(String strCommand){
Runtime rt = Runtime.getRuntime();
try {
Process p = rt.exec(strCommand);
if(p==null){
System.out.println("Error in process");
}
BufferedReader reader = new BufferedReader(new InputStreamReader(p.getInputStream()));
String line = null;
try {
while ((line = reader.readLine()) != null)
{
System.out.println(line);
}
} catch (IOException e) {
e.printStackTrace();
}
} catch (IOException e) {
e.printStackTrace();
}
}
I call this executeCommandLine() function from another function as follows:
public static void changeIpAddress(String strIpAddress, String strRootPassword, String strEthDevice){
String strCommandLine = "";
if(PLATFORM == PLATFORM_LINUX){
strCommandLine = "/bin/echo " + strRootPassword + "| sudo -S /sbin/ifconfig " + strEthDevice + " " + strIpAddress;
}else if(PLATFORM == PLATFORM_WINDOWS){
// TODO: Write for Windows
}else{
System.out.println("OS not supported");
}
System.out.println("Executed command:");
System.out.println(strCommandLine);
executeCommandLine(strCommandLine);
}

Android Ping command dies on unreachable server

I have been trying to attempt to insert a ping command thread into my Android application, and when the server is reachable the code works great. When the server is unreachable, the process hangs and I have no idea why.
This code works in the emulator, whether the host is resolvable or not, however on an actual device, the process.waitFor never returns, and no output is published from the input or output streams.
Any ideas?
protected double executePing(String ipAddress) {
List<String> commands = new ArrayList<String>();
commands.add("/system/bin/ping");
commands.add("-c");
commands.add("5");
commands.add("-w");
commands.add("5");
commands.add("128.128.128.128");
try {
this.doCommand(commands);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return laten;
}
private void doCommand(List<String> command) throws IOException{
ProcessBuilder pb = new ProcessBuilder(command);
Process process = pb.start();
// any error message?
StreamGobbler errorGobbler = new StreamGobbler(
process.getErrorStream(), "ERROR");
// any output?
OutputStreamGobbler outputGobbler = new OutputStreamGobbler(
process.getInputStream(), "OUTPUT");
// kick them off
errorGobbler.start();
outputGobbler.start();
// read the output from the command
try {
exitVal = process.waitFor();
//Sleep for 10 secs to try to clear the buffer
Thread.sleep(6000);
//pingVal = echo.toString();
if(exitVal == 0 && !pingVal.isEmpty()){
//System.out.println("PING STATS: "+pingVal);
try{
pingVal = pingVal.substring(pingVal.lastIndexOf("rtt min/avg/max/mdev"));
pingVal = pingVal.substring(23);
pingVal = pingVal.substring(pingVal.indexOf("/")+1);
laten = Double.parseDouble(pingVal.substring(0,pingVal.indexOf("/")));
}catch (IndexOutOfBoundsException ex){
System.out.println("PING VAL: "+ pingVal);
ex.printStackTrace();
}
}
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("ExitValue: " + exitVal);
}

One option would be to create a new thread to ping, and keep it open for a certain amount of time (call it a timeout). If you don't get the desired response, within the desired time, you can close the thread & try again; or, kill the process. This would give you the ability to check for specific response codes, along with the timeout.

Read from another process' output stream

i wanted to read the output-stream of a c-Application in my Java program. iremoted (available here: Link) is a C-Application that puts out seperate lines like "0x19 pressed" if a button on my Apple Remote is pressed. If i start the iremoted program everything is doing well and these separate lines are shown on my screen everytime I pressed a button.
Now I wanted to read the output-stream of the c-application in my Java application to process inputs of the Apple Remote in Java projects.
Unfortunately i don't know why no input is regocnized?
I tried it with a simple HelloWorld.c program and my program responded as intended in this case (prints out HelloWorld).
Why doensn't it work with the iremoted program?
public class RemoteListener {
public void listen(String command) throws IOException {
String line;
Process process = null;
try {
process = Runtime.getRuntime().exec(command);
} catch (Exception e) {
System.err.println("Could not execute program. Shut down now.");
System.exit(-1);
}
Reader inStreamReader = new InputStreamReader(process.getInputStream());
BufferedReader in = new BufferedReader(inStreamReader);
System.out.println("Stream started");
while((line = in.readLine()) != null) {
System.out.println(line);
}
in.close();
System.out.println("Stream Closed");
}
public static void main(String args[]) {
RemoteListener r = new RemoteListener();
try {
r.listen("./iremoted"); /* not working... why?*/
// r.listen("./HelloWorld"); /* working fine */
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

stdout is buffered and it's not automatically flushed if you are not writing to screen. Add:
fflush(stdout);
after:
printf("%#lx %s\n", (UInt32)event.elementCookie,
(event.value == 0) ? "depressed" : "pressed");

iremoted is likely writing to stderr if a hello world program works. You would want the error stream in that case. I'm not sure how this works for your hello world case - I think you're doing the wrong thing here:
new InputStreamReader(process.getInputStream());
should be
new InputStreamReader(process.getOutputStream());
or
new InputStreamReader(process.getErrorStream());