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Python 2.7 subprocess call method not working to run java command

I am trying to use a python script to manipulate the input files for my java program. The way I am doing it is I am generating the file name and passing it to subprocess.call() method to execute. Here is my program:
def execJava(self):
self.thisCmd="pause"
call(self.javaCmd,shell=True)
call(self.pauseCmd,shell=True)
Where,
self.javaCmd = 'java -ea -esa -Xfuture -Xss64m -classpath "C:\FVSDK_9_1_1\lib\x86_64\msc_12.0-sse2_crtdll\*" -Djava.library.path="C:\FVSDK_9_1_1\lib\x86_64\msc_12.0-sse2_crtdll;C:\FVSDK_9_1_1\lib\x86_64\share" com.cognitec.jfrsdk.examples.MatchFIRAgainstGallery C:\FVSDK_9_1_1\etc\frsdk.cfg 0 .\tmp\frsdk-scratch\probe_1.fir .\tmp\test\*'
Yes, it's a long complex java instruction but when I run it in the command prompt it works fine. Only when I pass it as a string it doesn't run and returns:
Exception in thread "main" java.lang.Error
After some exploration into the problem, I have discovered that it is due to \x, \t in the instruction, so it is executing
.\tmp\test\*
as
mp est\*
as it replaces \t with tab space while executing. I have looked up quite a bit and didn't find any solution. Any help is much appreciated.

Use forward slashes "/" instead of back slashes "\" for your paths.

Dollar Sign Character in Java

I am new to programming, but I am coming along. I am using the online IDE written in php from www.compilejava.net. My question is this. I tried to use this code and I took it directly out of a Java textbook:
class DollarArguement {
public static void main(String args[]) {
for(int i=0;i<args.length; i++) {
if(args[i].startsWith("$")) {
System.out.print(args[i]);
break;
}
}
}
}
It works for every character I have tried except "$". I would like to put multiple strings in the commandline and search for $ values. Does anyone know why this is not working? Thanks in advance.

I tested your code on OSX and it displayed no results for "$", but if i changed it to "." it printed the first result (because of the break statement).
The reason is that on OSX (and other Unix systems) the bash terminal is looking for values which start with $ as these signify variable names.
you can test this simply by typing in a terminal
echo Hi
Hi
echo $Hi
(no result)
I assume the strings with the $ prefix are never evening making it into the program.
You can escape the $ with a backslash. Try running your program with these backslashes in your parameters.
echo \$Hi
$Hi
eg.
java -cp . DollarArguement \$test
$test

Passing pre-escaped command-line arguments to ProcessBuilder

I bumped into this problem today when setting up a local set of communicating programs. Basically one of my applications is sending some data to another, and part of this data is a string containing a command to execute (like you would from the command-line). Let's say, for example:
g++ foo.cc bar.cc -o foobar
is the command sent by my first application. The second application, which receives the command (amongst other things), needs to execute this command after doing some other processing.
Now, at first I thought this would be trivial using a ProcessBuilder:
String exampleCommand = "g++ foo.cc bar.cc -o foobar";
ProcessBuilder builder = new ProcessBuilder(exampleCommand);
builder.start().waitFor();
However this is where the problem occurs.
CreateProcess error=2, The system cannot find the file specified
Okay, no worries I guess I can't just dump the whole thing into the builder. The first part of the command is usually a trivial string so I thought I could probably get away with a split around the first ' ' to separate the program name and arguments.
String exampleCommand = "g++ foo.cc bar.cc -o foobar";
String[] parts = exampleCommand.split(" ", 2);
ProcessBuilder builder = new ProcessBuilder(parts[0], parts[1]);
builder.start().waitFor();
And this brought me a little closer, the g++ file could now be found correctly, however after examining the stderr of g++ I found that the following error had occurred:
g++.exe: error: foo.cc bar.cc -o foobar: No such file or directory
At this point I realised that the ProcessBuilder class must be escaping all arguments passed to it in preparation for the command-line (hence the reason it usually takes arguments as an array of individual arguments rather than just a predefined argument string).
My question is, "Is there any way to pass a raw string of arguments to a ProcessBuilder and say THERE, execute EXACTLY this?"
Because the command comes from another application and is in no way static I can't just break the arguments down into an array beforehand and pass them to the ProcessBuilder constructor properly. The arguments are not so trivial that simply splitting the string around a ' ' will work properly either; arguments might contain spaces escaped with double quotes. For example:
g++ "..\my documents\foo.cpp" bar.cpp -o foobar
Could be a command coming from the application and splitting that string around ' ' and passing it to the ProcessBuilder will result in corrupt arguments.
If there is no proper way to do this can someone please point me to a standalone command line argument parser (in Java) that can turn a command-line string into a valid String[]?

Okay I feel rather foolish now but I achieved my desired result by simply reverting back to the good old Runtime.getRuntime().exec(...). I'll leave the question up in case anyone is as silly as me and find it useful.
String exampleCommand = "g++ foo.cc bar.cc -o foobar";
Runtime sys = Runtime.getRuntime();
sys.exec(exampleCommand);
Easy.

A comment to the Runtime.getRuntime().exec(...) solution:
The Runtime.getRuntime().exec(...) is not good anymore. In java executed on OSX El Capitan, 'Runtime.getRuntime().exec(...)' contains an error that sometimes closes the opened process when the java program exits. It works fine on previous OSX versions. However, ProcessBuilder works on all OSX versions.
(Haven't posted enough to have a enough rep points to make this as a normal comment.)

giving special characters at command line arguments

Hi all! I have written this program for reading command line arguments.
public class UseArgument {
public static void main(String args[])
{
System.out.print("hi, ");
System.out.print(args[0]);
System.out.println(" How are you?");
}
}
I tried to send the following argument through the command line:
java UseArgument #!&^%
and it's throwing an error as follows.
Output:
hi, #! How are you?
''%'' is not recognized as an internal or external command,
operable program or batch file.
java UseArgument #!^%
Can anybody explain this behavior? Does this relate to regular expressions?
Thanks.
sivakiran B

Some of the special characters you are using have a meaning to the shell from which you are launching your program. By putting the characters in quotes, you are instructing the shell not to process these characters according to their special meaning.

As a command it runs fine from cmd prompt but not from java code

The code given below actually tries running a command. This command when run from command prompt, produces the necessary output. But when i try to run the application from java code, it keeps on running and doesn't produce any output file.
String arg[]={"C:\\app1.exe", "C:\\app2.exe", "c:\\app3.exe"};
String pwd[]={"123","-x","-sf"};
String outputfile="c:\\output.xml"
String command=arg[0]+pwd[0]+arg[1]+pwd[1]+arg[2]+pwd[2]+output;
Process pr=rt.exec(command);

String command=arg[0]+pwd[0]+arg[1]+pwd[1]+arg[2]+pwd[3]+output;
At least you are missing the whitespace between the arguments!

You should not concatenate all arguments to one string. Instead, pass them as separate arguments to
Process exec(java.lang.String[])

I think you made mistake in generating command.
It would be
C:\\app1.exe123C:\\app2.exe-xc:\\app3.exe-sfc:\\output.xml
Make sure the space
And use this exec(String[]

My guess is that you haven't tried this in a debugger or printed what it is trying to run.
My guess is that when you make this compile, you don't have a command called.
C:\app1.exe123C:\app2.exe-xc:\app3.exe-sfc:\output.xml
You cannot have more than one : in the path.

You concatenate all commands and args, but you never insert spaces between the commands and args.
So your command looks like this: "C:\app1.exe123C:\app2.exe-xc:\app3.exe-sfc:\output.xml"
And also pwd[3] doesn't exist. You have an array with 3 elements, so the highest element would be pwd[2]. You should get and ArrayIndexOutOfBoundsException here (or is it just a copy-paste-mistake)?

Well there's a couple of things wrong with the code:
A space is needed between the commands and the arguments and pwd[3] is out of bounds. I ran this code and it works.
String arg[]={"C:\\app1.exe", "C:\\app2.exe", "c:\\app3.exe"};
String pwd[]={" 123"," -x"," -sf"};
String outputfile="c:\\output.xml";
String command=arg[0]+pwd[0]+arg[1]+pwd[1]+arg[2]+pwd[2]+outputfile;
try {
Process pr=Runtime.getRuntime().exec(command);
} catch (IOException e) {
e.printStackTrace();
}

Try:
String[] command = new String[] { arg[0], pwd[0], arg[1], pwd[1],
arg[2], pwd[2], output };
This is assuming the command you wish to run is
C:\app1.exe 123 C:\app2.exe -x C:\app3.exe -sf c:\output.xml
If you really want to run three separate commands, you will have to run exec() more than once.
See the javadoc at http://download.oracle.com/javase/1.4.2/docs/api/java/lang/Runtime.html#exec(java.lang.String[]) for details.
EDIT: As another answerer has pointed out, there is no pwd[3]!

If your apps "app1", "app2" ... are run from the command prompt you need open that before.
by launching cmd.exe first of all.
And then as others suggested add space between app and arguments.
Try by pasting this in the Run/Search input field in windows:
cmd.exe /K C:\app1.exe 123 C:\app2.exe
-x c:\app3.exe -sf c:\output.xml
cmd.exe /K keeps the propmt open after executing commands