execute pig command in Java program

[Dan Yi]

Hi, 

I used to write PHP code to execute pig command, it worked well,
Now I switch to Java but seems it won't work, here is my code:

String pigCommand = "pig -x local -p ouput=/tmp my_pig_script.pig";
                
                Runtime r = Runtime.getRuntime();
                Process p;
                
                int exitVal;

                try {
                        p = r.exec(pigCommand);
                        exitVal = p.waitFor();
                        BufferedReader br = new BufferedReader(new
InputStreamReader(p.getInputStream()));
                        String line = null;
                                        
                        while((line = br.readLine()) != null) {
                                System.out.println(line);
                        }
                        br.close();

                        System.out.println("exitVal: " + exitVal);
                        System.out.println("Done");



If I run the that pig command in console directly, it works, if I replace
that 
Pig command with other shell command say 'ping www.yahoo.com', and run the
java
Program, it works too. So what might be the problem?

Thanks.