calling shell script from java application

Question

I have a java application from which i am calling a shell script. Can any one tell where to keep the script file in my application and what is the path to access the file in whole application.

i m keeping my script in the java package but when i m trying to access using path like com.abc.script.sh by running my java application through unix i ma getting error java.io.IOException: error=2, No such file or directory

i am calling the script file with some argument with the following code

private static final String command = "com.abc.script.sh -db abc -scm TEST_xyz -bcp com.abc.out.txt -log /var/tmp -tab abc_$TABLENAME";

Process process = Runtime.getRuntime().exec(command);

and i am running the application from unix.

i need to pass the parameter to shell script file as well . the parameters are like hostname , table name...

Answer 1

Keep it in the directory where your Java class file is. That way you can simply use the Shell script file name. You can keep it elsewhere too, but you will have to change the path accordingly.

Answer 2

You could store your shell script as a resource (e.g. inside your jar file), then exec a shell and pipe the content of your script as standard input to the running shell.

Something like this (haven't tried it):

ProcessBuilder processBuilder = new ProcessBuilder( "/usr/bin/bash" );
Process process = processBuilder.start();
OutputStream outputStream = process.getOutputStream();
InputStream resourceStream = getClass().getResourceAsStream( 
        "/path/to/my/script.sh" );
IOUtils.copy( resourceStream, outputStream );

Answer 3

where to keep the script file in my application

Your wrote, I can interprete this like:

• Storing the content of the file into the memory
• Storing the file into your .jar file

I think you mean the second.

You can place it in your jar file in every folder you want. I prefer a subfolder (not the root)

First put the file in your jar. Then you have to extract it to a temporary file (See the link if you want to know how to make a tempfile).
Then create an inputstream from the file in your jar and copy the data to the temp-file.

InputStream is = getClass().getResourceAsStream("/path/script.sh");
OutputStream os = new FileOutputStream(tempFile);
byte[] buffer = new byte[1024];
int bytesRead;
while ((bytesRead = is.read(buffer)) != -1)
{
    os.write(buffer, 0, bytesRead);
}
buffer = null; // Clear the buffer

Then you have to execute your shellscript

Runtime.getRuntime().exec("terminalname " + tempFile.getAbsolutePath());

Maybe you can use this line to execute your script (I don't think this will work with your parameters):

java.awt.Desktop.getDestkop().open(tempFile);

I hope this is an answer for your question.

Answer 4

If you happen to be using the Spring framework for this project, a good and simple option is to store the shell script in a folder on your class path and use a ClassPathResource object to locate it.