Protecting command-line arguments from glob expansion

Question

Hi. I am writing a java program and I want to pass it a regular expression as a command-line argument. However, when I use certain regular expressions (e.g. [a-z]*), the java command-line interpreter recognizes this a glob expression and replaces it with names of files from the current directory.
I am running the java interpreter from a Linux bash command line and I am enclosing the regular expression in single quotes (e.g. '[a-z]*') to protect it from the bash interpreter but the java interpreter is still getting to it. I have read other posts which stated that the java interpreter doesn't do this and that it must be the operating system's command-line interpreter that is doing it but I am sure this not the case.
Can anyone help? Thank you. Eli

Answer 1

I am running the java interpreter from a Linux bash
command line and I am enclosing the regular
expression in single quotes (e.g. '[a-z]*') to
protect it from the bash interpreter but the java
interpreter is still getting to it. I have read other
posts which stated that the java interpreter doesn't
do this and that it must be the operating system's
command-line interpreter that is doing it but I am
sure this not the case.It most certainly is the case that it's the shell, not Java. If the VM receives the String [a-z]* then that will be one the args.
What may be happening is that java is actually a shell script, not an executable, and that shell script is expanding stuff.
Do this: $ type java You'll get something like java is /usr/local/bin/java Then do $ file /usr/local/bin/java or whatever comes back. (Or just try to view the file with a text editor.)
That file might be a shell script that sets some env vars and than calls the real java executable, passing it "$*" or "$@".
If that's the case, you can try just invoking the executable directly, or modifying that shell script so that it won't do the expansion.
If that's not the case, then post the exact command you're running and show your main method (includig code in the main that prints out each element of the args parameter).