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Opening cmd and waiting user input in cmd and exec commands from java

My problem is, after opening cmd from java code, i want user to be able to input like in c++ ms dos applications. When user writes sth such as "dir" or "cd..", i want to execute these codes by java.
The problem is for every command java re-opens cmd again. Also i cannot execute commands. My cmd start code is below ;
final ArrayList<String> commands = new ArrayList<>();
commands.add("cmd.exe");
commands.add("/C");
commands.add("start");
ProcessBuilder pb = new ProcessBuilder(commands);
Process process = pb.start();

Here's some cleaned up code from How to open the command prompt and insert commands using Java?
public static void main(String[] args) {
try {
String ss = null;
Runtime obj = null;
Process p = Runtime.getRuntime().exec("cmd.exe");
//write a command to the output stream
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(p.getOutputStream()));
writer.write("dir");
writer.flush();
//Get the input and stderror
BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream()));
BufferedReader stdError = new BufferedReader(new InputStreamReader(p.getErrorStream()));
System.out.println("Here is the standard output of the command:\n");
while ((ss = stdInput.readLine()) != null) {
System.out.println(ss);
}
System.out.println("Here is the standard error of the command (if any):\n");
while ((ss = stdError.readLine()) != null) {
System.out.println(ss);
}
} catch (IOException e) {
System.out.println("FROM CATCH" + e.toString());
}
}

java input.readLine hangs after starting a powershell script

We are trying to call a Powershell script via Java but it hangs when we try to read the output of that script. It hangs on "input.readLine()"
Here is a code we have tried:
String command = "cmd /c powershell C:\\_checkouts\\TestPowerShell\\passwordExpirationTime.ps1";
Process p = Runtime.getRuntime().exec(command);
new InputStreamReader(p.getInputStream());
BufferedReader input = new BufferedReader(new InputStreamReader(p.getInputStream()));
StringBuilder stringBuilder = new StringBuilder();;
for (String line = input.readLine(); line != null; line = input.readLine()) {
stringBuilder.append(line);
}
input.close();
String msg = stringBuilder.toString();
System.out.println("msg: " + msg);
We tried looking at this solution Java program hangs when trying to invoke powershell script
but none of those suggestions worked for us.
We also tried it without cmd /c and with cmd /k. We really want this as a generic class where any script could be called. i.e. BAT, BASH, SH, Powershell, etc.
Any ideas?
Thanks to the answer below here is the code that worked:
try{
final ProcessBuilder pb = new ProcessBuilder("powershell","C:\\psFile.ps1");
pb.redirectInput(Redirect.from(new File("NUL")));
final Process p = pb.start();
final int retcode = p.waitFor();
InputStream is = p.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
br.close();
}catch (Exception e){
e.printStackTrace();
}
Here's some additional information. Our powershell was returning an error because it was restricted. That is why we needed all the Redirect to NUL. Once we fixed that and it wasn't returning an error we were able to simplify our code to this:
try{
final ProcessBuilder pb;
pb = new ProcessBuilder(args);
final Process p = pb.start();
InputStream is = p.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
br.close();
}catch (Exception e){
e.printStackTrace();
}

Use a ProcessBuilder. Any process implying a modicum of I/O should outright refuse to run via Runtime.exec(), alas, it cannot detect that. And Oracle hasn't flagged it as #Deprecated which is a pity.
Anyway:
final File logFile = new File("/path/to/logfile");
final ProcessBuilder pb = new ProcessBuilder("powershell", "/path/to/the/ps1");
pb.redirectOutput(Redirect.to(logFile));
pb.redirectErrorStream(true);
final Process p = pb.start();
final int retcode = p.waitFor();
// deal with retcode
// read result from the log file

Error: Cannot open VM: "[datastore] myVM1/myVM1.vmx", unknown file suffix

I'm having a lot of difficulty running vmrun through ProcessBuilder in Java.
I have a command string like this:
java -cp . RunTest 'vmrun -T esx -h https://10.123.236.123:443/sdk -u root -p password revertToSnapshot "[datastore] myVM1/myVM1.vmx" snapshot1'
When you run the vmrun command above (without Java), the command executes successfully. But with Java, I receive the ff. error:
Error: Cannot open VM: "[datastore] myVM1/myVM1.vmx", unknown file suffix
The code is below:
public static void main(String args[]) {
runProcessBuilderMulti(args[0]);
}
static void runProcessBuilderMulti (String cmd){
List<String> list = new ArrayList<String>();
System.out.println("Running Command: "+cmd.replace("\"","\\\""));
Matcher m = Pattern.compile("([^\"]\\S*|\".+?\")\\s*").matcher(cmd);
while (m.find())
list.add(m.group(1));
System.out.println(list);
try {
Process process = new ProcessBuilder(list).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);
}
System.out.println(process.exitValue());
} catch (Exception e) {}
}
I used Runtime.exec() before switching to ProcessBuilder. I thought it had to do with the quotes, so I added the cmd.replace, but apparently it was a different issue.
Any help would be appreciated. Thanks!

I was playing around with ProcessBuilder when I learned it had trouble with piped commands using the above script. A bit more Googling found that ProcessBuilder needed to open a shell to execute certain commands.
ProcessBuilder b = new ProcessBuilder("/bin/sh", "-c", "ls -l | grep daemon");
The function is updated as below:
static void runProcessBuilderMulti (String cmd){
System.out.println("Running Command: "+cmd.replace("\"","\\\""));
try {
Process process = new ProcessBuilder("/bin/sh", "-c", cmd).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);
}
System.out.println(process.exitValue());
} catch (Exception e) {}
}
I'm guessing that longer commands are more difficult to process, like piped commands, so it needs its own shell for execution.

Running Command Line in Java [duplicate]

This question already has answers here:
Executing a Java application in a separate process
(9 answers)
Closed 7 years ago.
Is there a way to run this command line within a Java application?
java -jar map.jar time.rel test.txt debug
I can run it with command but I couldn't do it within Java.

Runtime rt = Runtime.getRuntime();
Process pr = rt.exec("java -jar map.jar time.rel test.txt debug");
http://docs.oracle.com/javase/7/docs/api/java/lang/Runtime.html

You can also watch the output like this:
final Process p = Runtime.getRuntime().exec("java -jar map.jar time.rel test.txt debug");
new Thread(new Runnable() {
public void run() {
BufferedReader input = new BufferedReader(new InputStreamReader(p.getInputStream()));
String line = null;
try {
while ((line = input.readLine()) != null)
System.out.println(line);
} catch (IOException e) {
e.printStackTrace();
}
}
}).start();
p.waitFor();
And don't forget, if you are running a windows command, you need to put cmd /c in front of your command.
EDIT: And for bonus points, you can also use ProcessBuilder to pass input to a program:
String[] command = new String[] {
"choice",
"/C",
"YN",
"/M",
"\"Press Y if you're cool\""
};
String inputLine = "Y";
ProcessBuilder pb = new ProcessBuilder(command);
pb.redirectErrorStream(true);
Process p = pb.start();
BufferedReader reader = new BufferedReader(new InputStreamReader(p.getInputStream()));
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(p.getOutputStream()));
writer.write(inputLine);
writer.newLine();
writer.close();
String line;
while ((line = reader.readLine()) != null) {
System.out.println(line);
}
This will run the windows command choice /C YN /M "Press Y if you're cool" and respond with a Y. So, the output will be:
Press Y if you're cool [Y,N]?Y

To avoid the called process to be blocked if it outputs a lot of data on the standard output and/or error, you have to use the solution provided by Craigo. Note also that ProcessBuilder is better than Runtime.getRuntime().exec(). This is for a couple of reasons: it tokenizes better the arguments, and it also takes care of the error standard output (check also here).
ProcessBuilder builder = new ProcessBuilder("cmd", "arg1", ...);
builder.redirectErrorStream(true);
final Process process = builder.start();
// Watch the process
watch(process);
I use a new function "watch" to gather this data in a new thread. This thread will finish in the calling process when the called process ends.
private static void watch(final Process process) {
new Thread() {
public void run() {
BufferedReader input = new BufferedReader(new InputStreamReader(process.getInputStream()));
String line = null;
try {
while ((line = input.readLine()) != null) {
System.out.println(line);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}.start();
}

Runtime.getRuntime().exec("java -jar map.jar time.rel test.txt debug");

import java.io.*;
Process p = Runtime.getRuntime().exec("java -jar map.jar time.rel test.txt debug");
Consider the following if you run into any further problems, but I'm guessing that the above will work for you:
Problems with Runtime.exec()

what about
public class CmdExec {
public static Scanner s = null;
public static void main(String[] args) throws InterruptedException, IOException {
s = new Scanner(System.in);
System.out.print("$ ");
String cmd = s.nextLine();
final Process p = Runtime.getRuntime().exec(cmd);
new Thread(new Runnable() {
public void run() {
BufferedReader input = new BufferedReader(new InputStreamReader(p.getInputStream()));
String line = null;
try {
while ((line = input.readLine()) != null) {
System.out.println(line);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}).start();
p.waitFor();
}
}

Have you tried the exec command within the Runtime class?
Runtime.getRuntime().exec("java -jar map.jar time.rel test.txt debug")
Runtime - Java Documentation

Process p = Runtime.getRuntime().exec("java -jar map.jar time.rel test.txt debug");

How to Execute Windows Commands Using Java - Change Network Settings

In Java, I want to be able to execute a Windows command.
The command in question is netsh. This will enable me to set/reset my IP address.
Note that I do not want to execute a batch file.
Instead of using a batch file, I want to execute such commands directly. Is this possible?
Here is my implemented Solution for Future Reference:
public class JavaRunCommand {
private static final String CMD =
"netsh int ip set address name = \"Local Area Connection\" source = static addr = 192.168.222.3 mask = 255.255.255.0";
public static void main(String args[]) {
try {
// Run "netsh" Windows command
Process process = Runtime.getRuntime().exec(CMD);
// Get input streams
BufferedReader stdInput = new BufferedReader(new InputStreamReader(process.getInputStream()));
BufferedReader stdError = new BufferedReader(new InputStreamReader(process.getErrorStream()));
// Read command standard output
String s;
System.out.println("Standard output: ");
while ((s = stdInput.readLine()) != null) {
System.out.println(s);
}
// Read command errors
System.out.println("Standard error: ");
while ((s = stdError.readLine()) != null) {
System.out.println(s);
}
} catch (Exception e) {
e.printStackTrace(System.err);
}
}
}

Runtime.getRuntime().exec("netsh");
See Runtime Javadoc.
EDIT: A later answer by leet suggests that this process is now deprecated. However, as per the comment by DJViking, this appears not to be the case: Java 8 documentation. The method is not deprecated.

Use ProcessBuilder
ProcessBuilder pb=new ProcessBuilder(command);
pb.redirectErrorStream(true);
Process process=pb.start();
BufferedReader inStreamReader = new BufferedReader(
new InputStreamReader(process.getInputStream()));
while(inStreamReader.readLine() != null){
//do something with commandline output.
}

You can run the command with Runtime.getRuntime().exec("<command>") (eg. Runtime.getRuntime().exec("tree")). But, this will only run executables found in path, not commands like echo, del, ... But only stuff like tree.com, netstat.com, ... To run regular commands, you will have to put cmd /c before the command (eg Runtime.getRuntime().exec("cmd /c echo echo"))

public static void main(String[] args) {
String command="netstat";
try {
Process process = Runtime.getRuntime().exec(command);
System.out.println("the output stream is "+process.getOutputStream());
BufferedReader reader=new BufferedReader( new InputStreamReader(process.getInputStream()));
String s;
while ((s = reader.readLine()) != null){
System.out.println("The inout stream is " + s);
}
} catch (IOException e) {
e.printStackTrace();
}
}
This works.

Runtime#exec().