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Run an exe file and insert some input to it with java

I have problem in running an exe file with java.
exe file process is like this : after run a command it ask for
password and when i insert password it does the job.
but in my java program I trying to run some commands with an exe file.
i invoke exe file an run my first command and after that i insert password with outputstream but t console get freez and it does nothing.
my code:
String command = "xxxx";
Process p = Runtime.getRuntime().exec(command);
BufferedWriter writer = new BufferedWriter(
new OutputStreamWriter(p.getOutputStream()));
writer.write("123456");
writer.close();
BufferedReader stdInput = new BufferedReader(new
InputStreamReader(p.getInputStream()));
BufferedReader stdError = new BufferedReader(new
InputStreamReader(p.getErrorStream()));
// read the output from the command
String s = null;
System.out.println("output of the command:\n");
while ((s = stdInput.readLine()) != null) {
System.out.println(s);
}
// read any errors from the attempted command
System.out.println(" error of the command (if any):\n");
while ((s = stdError.readLine()) != null) {
System.out.println(s);
}

Do input and get return message from console like Command Prompt in Windows

In the Command Prompt(cmd) of the Windows OS:
C:\>execution.exe --login user
Enter password:
Success
The work flow is entering the command->system returns message "Enter password:"->Input password->system returns message "Success".
How to do that in my code?
Here is mine, but It doesn't work.
Process p = Runtime.getRuntime().exec("execution.exe --login user");
BufferedWriter writer = new BufferedWriter(
new OutputStreamWriter(p.getOutputStream()));
writer.write("mypassword\n");
writer.flush();
writer.close();
BufferedReader stdInput = new BufferedReader(new
InputStreamReader(p.getInputStream()));
BufferedReader stdError = new BufferedReader(new
InputStreamReader(p.getErrorStream()));
// read the output from the command
System.out.println("System returns message:\n");
String s = null;
while ((s = stdInput.readLine()) != null) {
System.out.println(s);
}
// read any errors from the attempted command
System.out.println("System returns error message:\n");
while ((s = stdError.readLine()) != null) {
System.out.println(s);
}

Java InputStream to string

in my java program, i am trying to get the InputStream from a process and print it with this piece of code:
try {
Process p = Runtime.getRuntime().exec("cmd /c start dammage\\4.simulation.cmd");
//BufferedReader br = new BufferedReader(new InputStreamReader(p.getInputStream()));
//StringBuffer sb = new StringBuffer();
//String line;
//while ((line = br.readLine()) != null) {
//sb.append(line).append("\n");
//}
//System.out.println(sb.toString());
String input = IOUtils.toString(p.getErrorStream());
System.out.println(input);
} catch (IOException ex) {
Logger.getLogger(UI.class.getName()).log(Level.SEVERE, null, ex);
JOptionPane.showMessageDialog(this, "Something happened");
}
I tried both ways shown above (commented and uncommented), but none of them prints anything. So i would like to ask what am i doing wrong here?
I appreciate any help.

The buffered reader solution looks fine. You might be looking in the wrong stream. Try getting from both streams.. Like
BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream()));
BufferedReader stdError = new BufferedReader(new InputStreamReader(p.getErrorStream()));
StringBuffer sb = new StringBuffer();
String line;
//Read the output from the command
while ((line = stdInput.readLine()) != null) {
sb.append(line).append("\n");
}
//read any errors from the attempted command
while ((line = stdError.readLine()) != null) {
sb.append(line).append("\n");
}

Are you sure it should print something? Because, the commented code should work just right provided the command executed is returning non-empty input stream. Try replacing the argument of exec to "cmd". And see if it's able to read from the input stream. Do following. On windows machine it should give you welcome message from cmd (the usual welcome message we get after we run start command prompt).
Process p = Runtime.getRuntime().exec("cmd");
About the uncommented code, How IOUtils work? Does it read from the error stream repeatedly. Because, IMO, it's just one time read and not the repetitive one.
Hope I don't confuse.

You should add a p.waitFor(); to give the program time to terminate. Also, verify if you really want to read stdout or stderr
This works for me:
Process p = Runtime.getRuntime().exec("cmd /c java -version");
int ret = p.waitFor();
System.out.println("process terminated with return code: " + ret);
BufferedReader br = new BufferedReader(new InputStreamReader(p.getErrorStream()));
StringBuffer sb = new StringBuffer();
String line;
while((line = br.readLine()) != null) {
sb.append(line).append("\n");
}
System.out.println(sb.toString());

empty ProcessBuilder InputStream

I have some problems using the java ProcessBuilder.
I want to get my gpg keys, so I use the following code:
ProcessBuilder builder = new ProcessBuilder("C:\\[path]\\GnuPG\\pub\\gpg.exe", "--list-keys");
//builder.directory(new File("C:\\[path]\\GnuPG\\pub\\"));
Process process = builder.start();
Scanner s = new Scanner(process.getInputStream()).useDelimiter("\\Z");
System.out.println(s.next());
s.close();
But I always get a NoSuchElementException when executing s.next().
If I use the gpg command "-h", I always get the expected output.
If I change the Constructor call to
new ProcessBuilder("cmd", "/c", "C:\\[path]\\GnuPG\\pub\\gpg.exe", "--list-keys");
it sometimes works. But most times it doesn´t.
WHY? Can anyone help? THANKS!!

Try this-
Test test = new Test();
List<String> commands = new ArrayList<String>();
commands.add("C:\\[path]\\GnuPG\\pub\\gpg.exe");
commands.add("--list-keys");
test.doCommand(commands);
}
public void doCommand(List<String> command)
throws IOException
{
String s = null;
ProcessBuilder pb = new ProcessBuilder(command);
Process process = pb.start();
BufferedReader stdInput = new BufferedReader(new InputStreamReader
(process.getInputStream()));
BufferedReader stdError = new BufferedReader(new InputStreamReader
(process.getErrorStream()));
StringBuffer start= new StringBuffer();
// read the output from the command
System.out.println("Here is the standard output of the command:\n");
while ((s = stdInput.readLine()) != null)
{
start.append(s);
System.out.println(s.toString());
}
stdInput.close();
// read any errors from the attempted command
System.out.println("Here is the standard error of the command (if any):\n");
while ((s = stdError.readLine()) != null)
{
start.append(s);
System.out.println(s);
}
}

Writing the Output of an Operating System Command to the Console

I want to execute an operating system command in Java, and then print out it's returned value. Like this:
This is what I am trying...
String location_of_my_exe_and_some_parameters = "c:\\blabla.exe /hello -hi";
Runtime.getRuntime().exec(location_of_my_exe_and_some_parameters);
I tried putting a System.out.print() on the beginning of my Runtime... line, but it failed. Because, apparently, getRuntime() returns a Runtime object.
Now, the problem is, when I execute the "blabla.exe /hello -hi" command in command line, I got a result like: "You executed some command, hurray!". But, in Java, I got nothing.
I tried putting the return value into a Runtime object, to an Object object. However, they both failed. How can I accomplish this?
Problem Solved - this is my solution
Process process = new ProcessBuilder(location, args).start();
InputStream is = process.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}

Notice that Runtime.exec(...) returns a Process object. You can use this object to capture its input stream and retrieve whatever it prints to the standard output:
Process p = Runtime.getRuntime().exec(location_of_my_exe_and_some_parameters);
InputStream is = p.getInputStream();
// read process output from is

You can capture the output of a command using this:
Runtime rt = Runtime.getRuntime();
Process pr = rt.exec(command);
BufferedReader input = new BufferedReader(new InputStreamReader(pr.getInputStream()));
String line=null;
while((line=input.readLine()) != null) {
log.info(line);
}
//This will wait for the return code of the process
int exitVal = pr.waitFor();

UseProcessBuilder instead of Runtime.
Like:
Process process = new ProcessBuilder("c:\\blabla.exe","param1","param2").start();
Answer:
Process process = new ProcessBuilder("c:\\blabla.exe","/hello","-hi").start();
InputStream is = process.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
System.out.printf("Output of running %s is:", Arrays.toString(args));