Change sample for Java <1.9

Author: Ian Craggs

org.eclipse.paho.sample.mqttclient/src/main/java/org/eclipse/paho/sample/mqttclient/mqttv3/MqttV3Connection.java

@@ -71,7 +71,7 @@ public MqttV3Connection(CommandLine cliOptions) throws URISyntaxException {
 		// If the client ID was not set, generate one ourselves
 		if (clientID == null || clientID == "") {
 			// No client ID provided, generate one from the process ID
-			long pid = ProcessHandle.current().pid();
+			long pid = Thread.currentThread().getId(); //ProcessHandle.current().pid();
 			clientID = "mqtt-client-" + pid;
 		}
 

org.eclipse.paho.sample.mqttclient/src/main/java/org/eclipse/paho/sample/mqttclient/mqttv5/MqttV5Connection.java

@@ -72,7 +72,7 @@ public MqttV5Connection(CommandLine cliOptions) {
 		// If the client ID was not set, generate one ourselves
 		if (clientID == null || clientID == "") {
 			// No client ID provided, generate one from the process ID
-			long pid = ProcessHandle.current().pid();
+			long pid = Thread.currentThread().getId(); //ProcessHandle.current().pid();
 			clientID = "mqtt-client-" + pid;
 		}