Pls Help:Running a C executable from my Java Code

I am trying to run a C/C++ executable a.out from my Java code but its not working pls help me out...Its very very important

I am writing a segment of the code pls point out if i am making any mistakes

publicvoid itemStateChanged(ItemEvent a)

{

int i=c1.getSelectedIndex();

Runtime r=Runtime.getRuntime();

try

{

if(i==0);

if(i==1);

if(i==2);

if(i==3)

{

r.exec("./prog/a.out");

System.exit(0);

}

}catch(Exception e){}

}

I am working in UNIX enviornment

[1097 byte] By [selecaoa] at [2007-10-3 8:14:35]