Executing shell script from java

Hi,
I am trying to execute shell script from java, the shell script interns call the sql file.
When shell script is called it connect to database sucessfully but when sql file is called it is giving below error.
SP2-0310: unable to open file ".sql".
When I run the line explicitly in cygwin it works fine.
sqlplus -s $DBConnect @test.sql. I even given the read/write/execute permission to the sql file still it is not working.
I know this query is not related to Java instead to shell scripting, but i didnt find the correct forum to post.

Thanks,