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How to fire command in Ubuntu Terminal using Java code

How to select a directory and fire a command via Terminal using java code in Ubuntu.
For example i want to select the directory of tomcat like "cd /home/sree/tomcat/bin" and fire command like "sh shutdown.sh" and "sh startup.sh" for accessing sh files using java coding.
Also need help for the above process in windows operating system.
Please any one give me a solution. Thanks in advance

You could use Apache Commons CLI to create a program that calls the desired commands you want (you would need to create a version for both Ubuntu and Windows). It offers a lot of flexibility and possibility to plugin to the system pipelines.
After that, you package your program as a jar and run it from the directory you need.

Use the following function:
java.lang.Runtime.getRuntime().exec("a-command");
also, this post may help you:
http://blog.art-of-coding.eu/executing-operating-system-commands-from-java/

There are two classes for this,
java.lang.Runtime
More details
http://docs.oracle.com/javase/7/docs/api/java/lang/Runtime.html
java.lang.ProcessBuilder
More details
http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/ProcessBuilder.html
ProcessBuilder in Java
I have used process builder, for that you need to create an instance of ProcessBuilder first and call the start method on it, pass the command that you want to execute as constructor arguement.
ProcessBuilder pb = new ProcessBuilder("ls");
Process p = pb.start();
p.destroy();

Not able to execute a cmd file in java

I have to execute a xyz.cmd file which is in a directory E:/abc. So the absolute path of the file to be executed is E:/abc/xyz.cmd. When executed, a new window is created by the file itself.
My code snippet is:-
String path = “E:\\abc”;
String cmd = path + “\\xyz.cmd”;
ProcessBuilder processBuilder = new ProcessBuilder(cmd);
processBuilder.redirectErrorStream(true);
processBuilder.directory(new File(path));
processBuilder.start();
This does not work, but gives no error or exception. But the cmd file works fine, it can be executed manually from its directory using explorer or cmd-prompt.
Tried using different versions of jdk, but in vain. I am using windows 7 OS. I do not see the process running in the Task Manager also.
Any idea what is going wrong? The same code works fine in a different computer with the same config.
===EDIT====
Can this be a security issue? Something like the user executing the program is not having enough priveleges to execute a file?

You need to call cmd.exe as first part of your process builder String in order for the command processor to be able to call the .cmd file. This is also true for .bat files, or any OS type command. For example, please look here.
Also, please look here: When Runtime.exec() won't
Edit
You state:
please understand, this is not the problem of not adding cmd.exe in the processbuilder; because of the previous commands, cmd.exe will be taken care.
I see no documentation in your posts so far that this is true, and all my experience strongly suggests otherwise.
You also state:
Can this be a security issue? Something like the user executing the program is not having enough priveleges to execute a file?
No way to know unless you capture and display the process's input stream. In fact if you don't capture this stream, you could prevent your process from functioning at all. Often we have to also capture the error stream as well, but you've combined them with
processBuilder.redirectErrorStream(true)
Please read my "When Runtime.exec() won't" link above for more on the necessity of capturing streams.

How do I open a .bat containing a GUI in a java program in Linux?

everyone. I'm quite new here so please be tolerant if I make any mistakes.
I have a .bat file containing a command line to open up a .jar file that contains a program that has a GUI in it. The only line that's in the .bat file is:
java -jar "NewServer.jar"
I've been trying to use Runtime() to get this to run, but most the instructions I find to open a .bat file in a java program are for Windows. I'm currently using Fedora 12 (don't tell me to upgrade, I can't) if that makes a difference and programming using Eclipse. I also found this ProcessBuilder thing, but I couldn't get it to work so unless you have very explicit directions on how to use it, please don't include it in your answer. I would much rather use Runtime. It looked simpler.
Here's my code to test using Runtime in a java program. I'm hoping that if I can get this to work, I can get it to work in my real program.
import java.io.IOException;
public class testbat {
public static void main(String[] args) {
Process proc = null;
try {
proc = Runtime.getRuntime().exec("./ myServer.bat");
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("Cool");
}
The last line is just there for me to see if the program actually ran in case the GUI doesn't open. Also, I've already tried many combinations of things to include in the area after ".exec". I've tried using a path like "~/user/workspace/ProjectServer/dist/myServer.bat" to no avail.
I also already know that .bat files are for windows, but I'm able to execute it in linux, so I don't know if that makes a difference. I also tried using a .sh file the same way and it didn't work.
Please bear in mind that I'm not that great at Java, but I had to use it for this particular program, so if your answers could be really descriptive that would be awesome.

Just take that line out of the bat file, and run it. Yo're making it too hard.
$ java -jar "NewServer.jar"
will work. The quotes aren't necessary, so
$ java -jar NewServer.jar
will work as well. If you want to have the equivalent of your bat file, create a file named, say, run_newserver containing that line. Change its mode to executable:
$ cat > run_newserver
java -jar NewServer.jar
^D
$ chmod a+x run_newserver
$ ./run_newserver
Ideally, since you shouldn't have scripts without comments, do this. In your favorite editor, create a file run_newserver containing
#!/usr/bin/env bash
java -jar NewServer.jar
and chmod that. The line with #! -- often called a "shebang line" -- is UNIX magic that lets you say what interpreter you want. The program env in usr/bin finds your program and runs it (needed because different systems put bash in different directories.)
You could even put explanatory comments in the file too.
I'm a little unclear why you want to use Runtime#exec to run it at all -- it seems you'll just need a shell script to start that program.

Why are you using Java to run a Batch file, that in turn runs a Java program? Why have Batch in the loop at all? Just put the jar in your classpath and call it directly.

Batch (.bat) files are only for Windows environment. So, Try using shell script
Process proc = Runtime.getRuntime().exec("myServer.sh");

Just open up terminal and do this
vi /dir/to/exec/exec.sh
tap "i" and write this
#!/bin/sh
java -jar "NewServer.jar"
or if you want to run it in the background
#!/bin/sh
java -jar "NewServer.jar" & > /tmp/JavaServer.log
hit esc and type ":wq" and you have saved the file.
type this into the terminal
chmod +x /dir/to/exec/exec.sh
this give executable privileges and then you should run the file like
sh /dir/to/exec/exec.sh

Process is only initialized by your first call. You need to run:
proc.waitfor();
to get it to actually run your app.

How to execute commands using java [duplicate]

This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
Java execute a command with a space in the pathname
I am having following command
i_view32.exe C:\*.bmp /import_pal=C:\default.pal /convert=D:\temp\*.bmp
Which when i run through command prompt works fine.
I am trying to run the same command with the help of java.
Process p = Runtime.getRuntime().exec(System.getenv("ProgramFiles")+"\\IrfanView\\i_view32.exe c:\\*.bmp /import_pal= 1.pal /convert=d:\\temp\\*.bmp");
But i am not able to get Output in d:\\temp\\ Folder. Can any one suggest me where i am wrong.
Thanks in Advance..
Is there any other way to give "/" as i am using slash /import_pal=

2 your attempts are not exactly the same. I think that you executed command from command prompt when you were in c:\Program Files\IrfanView. When you are trying to run the same command from java you mention the full path. Since some programs are sensitive to current working directory I'd recommend you first to try to run the command from other directory (e.g. from c:) but specify full path.
If it works manually but does not work from java try to use ProcessBuilder instead of Runtime.exec(). Actually it is almost the same but it more Object Oriented and allows to specify working directory separately. I hope this will work for you.
If not try to play with quotes. Directory path 'c:\Program Files' contains space, so the path should be quoted.
Good luck.

Try to execute CMD
Example:
proc = Runtime.getRuntime().exec("cmd.exe /c dir");
It should work something like this, for your example it's a bit more complicated, but try it this way.

Trying to rename a computer OR execute a .bat file in Java

I'm trying to write a script to rename a computer (among other things) but just can't seem to figure it out. I don't really care what method I use to change the computer as long as i can change it. I found out how to read the computer name by doing
String computername = InetAddress.getLocalHost().getHostName();
However, that doesn't seem to offer any help in setting the computer name. Is there a way to set the Computer Name directly in the java console?
If not, or if anyone has better experience in this area, I also wrote a script using powershell 2.0 that renames the computer. I'm trying to figure out how to run that using
Runtime rt = Runtime.getRuntime();
Process proc = rt.exec("file location");
I followed the guide here but when trying to run a test .bat file that should just open the command line I just get this output in the java console:
C:\Users\Stephen\Desktop\opencmd.bat is found
OUTPUT>
OUTPUT>C:\Users\Stephen\workspace\UNM computer rename>cmd.exe
OUTPUT>Microsoft Windows [Version 6.1.7601]
OUTPUT>Copyright (c) 2009 Microsoft Corporation. All rights reserved.
OUTPUT>
It looks like it's just spitting back the command line output into the java console, instead of just running the command and opening the cmd line.
I would really appreciate input as I'm in a crunch for time here, thanks!

First, JDK really does not provide pure java API that allows changing computer name. So you have to run script.
Second, if you want to run script using Runtime you have to provide correct command line. So first try to run your script manually. I believe it accepts a least one parameter (the new computer name). So run it from command prompt and see it is working. Then put it to the working directory of your java program and copy/paste the command line into the java code and see that it is working now. if you want you can read STDOUT of your script and/or get its return code. If you do not care about its output just call process.waitFor() and then get the return code.
Be careful with arguments. Windows computer name may contain unicode characters and spaces. If it contains spaces surround it with quotes. Concerning unicode just try. I hope it will not cause problems to you.
You can also use ProcessBuilder class that allows better and more portable arguments passing.
Good luck.

It looks like opencmd.bat is being executed, so assuming your PowerShell script works, is it possible you don't have administrative privileges?
You can also do it elegantly using JNA, I think this would be the target. But if you are rushed for time, don't bother.