Running programs from within other programs

Question

I have a problem with running small java-applications form within another.
If I put the BufferedReader for errors first, sometimes it gets stuck
(without throwing any exceptions) when I want to run applications that
are working without any errors, when I run them manually. But if I put
the standardoutput-Reader first, it gets stuck (again without throwing
any exceptions), when an error occurs. This "getting stuck" always happens
in the line where the "while" is. It seems that nothing can be read, but its
not null too.
Thats part of my code:
String cmd = "java -cp rightDirectory MyFile";
Runtime rt = Runtime.getRuntime();
Process pr = rt.exec(cmd);
BufferedReader pout = new BufferedReader(new InputStreamReader(pr.getErrorStream()));
String line2;
while ((line2 = pout.readLine()) != null) {
System.out.println(line2);
pout.close();
BufferedReader peout = new BufferedReader(new InputStreamReader(pr.getInputStream()));
String line;
while ((line = peout.readLine()) != null) {
System.out.println(line);
peout.close();
How can this be done, that it works for all cases?

Answer 1

hi, Have you read http://www.javaworld.com/javaworld/jw-12-2000/jw-1229-traps.html ?