private static SshjSshClient getSSHClient(String host, String privateKey) {
		final LoginCredentials credential = LoginCredentials
				.fromCredentials(new Credentials("ubuntu", privateKey));
		final HostAndPort socket = HostAndPort.fromParts(host, 22);
		final SshjSshClient client = new SshjSshClient(
				new BackoffLimitedRetryHandler(), socket, credential, 5000);
		return client;
	}
Verifies the specified path exists on remote machine.
@param host The host where the file exists.
@param privateKey ssh private key credential
@param path path to file or directory
@return true if file exists else false.
spring-xd-integration-test/src/main/java/org/springframework/xd/integration/util/StreamUtils.java