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How to get command prompt output in java?

How to get the output of the command prompt which means i have opend a command prompt like this.
Process process = Runtime.getRuntime().exec("cmd /c start cmd.exe /K \"C:\\Editor\\editorTemp.exe\"");
i can not get the cmd output like this
BufferedReader br = new BufferedReader(new InputStreamReader(process.getInputStream()));
String line = null;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
So how can i get the command prompt output ?

This is not Java question. Basically what you doing is running Java (Java Main Process A) and from it starting another process (Windows CMD B). This is fine and you can get input/output streams of this process (B) in Java(A).
However this process (B) starts another process (again Windows CMD C) with its own standard input/output. This process has nothing common with processes A&B and uses Windows' standard Input/Output streams. So, there are no connections between A and C.
I'm not sure but I think there are some ways to run Windows CMD with different or not standard IO. Maybe something like this will work:
cmd <tty >tty
but there is no tty in Windows. Pragmatically you can do this as described here - Creating a Child Process with Redirected Input and Output but that would not work for regular CMD.
Nevertheless it became even more problematic when you start your own process from the editorTemp.exe (process D). D has even more disconnection with process A. And all for what? What don't you simply start process D directly from A and have full control on the IO streams and process itself?
Here is good example how to do so.

Your java thread is working independently of CMD call. The java code is beating the STDOUT pipe before anything is written.
If you call Process.waitFor(), it will wait until the CMD call is done. The STDOUT should be in the buffer, and then you can read it.

When you do a readLine(), your java thread is blocked until you have an actual full line or the input stream is closed.
If the program prints a partial line (without CR or LF at the end), and then waits for input, the readLine will be stuck.
So you will need to read character by character, until you think the proces has no more things to say.
See e.g. Is it possible to read from a InputStream with a timeout?

import java.util.Scanner;
Inside the main write this.
Scanner output = new Scanner(System.in);
System.out.println(“Enter your name”);
String name = output.next();
If you want user to enter an int then you need to do this.
int number = output.nextInt();

Getting too many arguments error while executing tr command from java

file = D:\Unix\tr.exe "Æ" "~" < "C:\SourceFiles\source.csv" > "D:\tgt"
When i execute this command using the below code in java
Process process = Runtime.getRuntime().exec(file);
am getting the following error
D:\Unix\tr.exe: too many arguments
PS : File contains Æ characters am trying to replace all those characters with ~
Any suggestions please ?

You're passing unicode in the CMD, I guess that causes the problem.
Set chcp xxx on the CMD and try.
refer below link for chcp codes
https://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/chcp.mspx?mfr=true

You have to program the io redirection yourself. This is usually the bash that takes care of it.
The result of the exec() call is a process. This process can then be used to get the STDIN of the process. Send the data to that process using that stream.
The way you call it, you send another command line option to tr, which is the < and > redirectors and the filenames.
Process process = System.getRuntime().exec(strBatchFileName);
OutputStream stdin = process.getOutputStream();
sendFileToStream(out);
InputStream stdout = process.getInputStream();
loadResultFromStream(stdout);
This is a pseudocode example, where sendFileToStream(...) feeds the input file into the TR process, and the loadResultFromStream(...) will load the result.
You may need to utilize threads to feed and read if the data is larger than the stream's buffer.
The question is kind of a duplicate and you will find a ProcessBuilder example here: Runtime's exec() method is not redirecting the output

Trying to execute a Java jar with Runtime.getRuntime().exec()

In the project I am working on, I need to execute a script that I have in a resources folder -- in the class path. I am simply testing the final script functionality, since I am on Windows, I needed a way to output a file to STDIN so I created a simple cat.jar program to clone unixs cat command.
So when I do "java -jar cat.jar someFile.txt" it will output the file to stdout. I'm sure there are different ways of doing what I did.
Anyways,
I want to run that JAR from my main java program.
I am doing
Runtime.getRuntime().exec("java -jar C:/cat.jar C:/test.txt");
I've tried switching the forward slash to a backward slash and escaping it -- didn't work.
Nothing is getting sent to standard out.
Where as, if I run the cat jar on its own, I get the file directed to standard out.
What am I doing wrong here?
Is this enough information?

Use the Process instance returned by exec()
Process cat = Runtime.getRuntime().exec("java -jar C:/cat.jar C:/test.txt");
BufferedInputStream catOutput= new BufferedInputStream(cat.getInputStream());
int read = 0;
byte[] output = new byte[1024];
while ((read = catOutput.read(output)) != -1) {
System.out.println(output[read]);
}
References:
http://docs.oracle.com/javase/7/docs/api/java/lang/Process.html
By default, the created subprocess does not have its own terminal or console. All its standard I/O (stdin, stdout, stderr) operations will be redirected to the parent process, where they can be accessed via the streams obtained using the methods getOutputStream(), getInputStream(), and getErrorStream().
http://docs.oracle.com/javase/7/docs/api/java/lang/Process.html#getInputStream()
getInputStream() returns the input stream connected to the normal output of the subprocess.

shell script to redirect the output

I am looking for a help regarding a shell script to redirect the output of a command to a file. I have a C program that reads the input from a serial port and display. I want this data to be redirected to a file. I am executing this from a java program by calling
Runtime r = Runtime.getRuntime();
Process procObj = r.exec("sh " + scriptfile);
I have tried writing the script file as
./program >> file.txt
The file.txt is not getting updated. Here, the program doesn't end until the connection to the port is lost, in a sense it is infinitely running. So my program keeps looking for data on the port and display as and when it is there.
I just need to redirect the same output to a file that I would use as a log.
I looked at How to make shell output redirect (>) write while script is still running? but not helpful.
Kindly help..

How much output does program generate? Using standard IO redirection will add a 4KB buffer between stdout and file. This means your program must output more than 4KB of data before the OS starts to write to the file.
To fix this, add stdout.flush() to your program when a "work unit" is complete (maybe a line but might be more than one line).

Can you try ./program >> file.txt 2>>file.txt, or ./program 2>&1 >>file.txt?

just try this
List<String> cmd = new ArrayList<String>();
cmd.add("sh");
cmd.add("-c");
cmd.add("program 1> file.txt 2>&1");
ProcessBuilder pb = new ProcessBuilder(cmd);
Process p = pb.start();

If you use standard C calls for output (printf, puts etc.), your output may get buffered. On C89 and onwards, it depends on the buffering mode (unbuffered, fully buffered, line buffered) and on the size of the buffer, whether your output is buffered at all and when the buffer is flushed (see http://www.gnu.org/software/libc/manual/html_node/Buffering-Concepts.html and man setvbuf).
By default, output to a file is fully buffered on Linux. If you want the output to appear immediately in the output file, you may:
use fflush() after each output operation
use the system call write() (man 2 write)
switch off buffering: setvbuf(stdout, NULL, _IONBF, 0); (https://stackoverflow.com/a/7876756/601203)
This behaviour is not related on the fact the you start your C program in a Java program via a shell script. This behaviour depends on the standard C library that you have linked into your program.

How to write in Java to stdin of ssh?

Everything works fine on the command line, but when I translate what I want into Java, the receiving process never gets anything on stdin.
Here's what I have:
private void deployWarFile(File warFile, String instanceId) throws IOException, InterruptedException {
Runtime runtime = Runtime.getRuntime();
// FIXME(nyap): Use Jsch.
Process deployWarFile = runtime.exec(new String[]{
"ssh",
"gateway",
"/path/to/count-the-bytes"});
OutputStream deployWarFileStdin = deployWarFile.getOutputStream();
InputStream deployWarFileStdout = new BufferedInputStream(deployWarFile.getInputStream());
InputStream warFileInputStream = new FileInputStream(warFile);
IOUtils.copy(warFileInputStream, deployWarFileStdin);
IOUtils.copy(deployWarFileStdout, System.out);
warFileInputStream.close();
deployWarFileStdout.close();
deployWarFileStdin.close();
int status = deployWarFile.waitFor();
System.out.println("************ Deployed with status " + status + " file handles. ************");
}
The script 'count-the-bytes' is simply:
#!/bin/bash
echo "************ counting stdin bytes ************"
wc -c
echo "************ counted stdin bytes ************"
The output indicates that the function hangs at the 'wc -c' line -- it never gets to the 'counted stdin bytes' line.
What's going on? Would using Jsch help?

You might try closing the output stream before you expect wc -c to return.
IOUtils.copy(warFileInputStream, deployWarFileStdin);
deployWarFileStdin.close();
IOUtils.copy(deployWarFileStdout, System.out);
warFileInputStream.close();
deployWarFileStdout.close();

Would using Jsch help?
Using JSch would only help if you would be using the setInputStream() and setOutputStream() methods of the channel instead of the IOUtils.copy method, since they manage the copying on a separate thread.
ChannelExec deployWarFile = (ChannelExec)session.openChannel("exec");
deployWarFile.setCommand("/path/to/count-the-bytes");
deployWarFile.setOutputStream(System.out);
deployWarFile.setInputStream(new BufferedInputStream(new FileInputStream(warFile)));
deployWarFile.connect();
(Here you somehow have to wait until the other side closes the channel.)
If you simply replaced the Runtime.exec with opening an ChannelExec (and starting it after getting the streams), the problem would be completely the same, and could be solved by the same solution mentioned by antlersoft, i.e. closing the input before reading the output:
ChannelExec deployWarFile = (ChannelExec)session.openChannel("exec");
deployWarFile.setCommand("/path/to/count-the-bytes");
OutputStream deployWarFileStdin = deployWarFile.getOutputStream();
InputStream deployWarFileStdout = new BufferedInputStream(deployWarFile.getInputStream());
InputStream warFileInputStream = new FileInputStream(warFile);
deployWarFile.connect();
IOUtils.copy(warFileInputStream, deployWarFileStdin);
deployWarFileStdin.close();
warFileInputStream.close();
IOUtils.copy(deployWarFileStdout, System.out);
deployWarFileStdout.close();
(Of course, if you have longer output, you will want to do input and output in parallel, or simply use the first method.)

You probably get an error, but the process hangs because you are not reading the error stream.
Taken from the Process JavaDoc
All its standard io (i.e. stdin, stdout, stderr) operations will be redirected to the parent process through three streams (Process.getOutputStream(), Process.getInputStream(), Process.getErrorStream()). The parent process uses these streams to feed input to and get output from the subprocess. Because some native platforms only provide limited buffer size for standard input and output streams, failure to promptly write the input stream or read the output stream of the subprocess may cause the subprocess to block, and even deadlock.
So you need to read all of them. Using the ProcessBuilder is probably easier