Mark S. Kolich - Remember to Close Your Streams When Using Java's Runtime.getRuntime().exec()

That said, the undocumented proper way of handing a Process object and its corresponding I/O streams is to wrap the exec() call in a try-finally block, closing the STDOUT, STDIN, and STDERR streams when you’re done with the Process object. The abstract class java.lang.Process exposes these three streams to you via getOutputStream(), getInputStream() andgetErrorStream() which you must explicitly close.

Process p = null;
try {
  p = Runtime.getRuntime().exec(...);
  // Do something with p.
} finally {
  if(p != null) {
    closeQuietly(p.getOutputStream());
    closeQuietly(p.getInputStream());
    closeQuietly(p.getErrorStream());
  }
}

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