TestShell(String rootPass, String instanceName, String zookeepers, String configFile) throws IOException {
// start the shell
output = new TestOutputStream();
input = new StringInputStream();
PrintWriter pw = new PrintWriter(new OutputStreamWriter(output));
shell = new Shell(new ConsoleReader(input, output), pw);
shell.setLogErrorsToConsole();
shell.config("-u", "root", "-p", rootPass, "-z", instanceName, zookeepers, "--config-file", configFile);
exec("quit", true);
shell.start();
shell.setExit(false);