Bug: 484264 - Null pointer in Paho Java client WebSocket classes

Added better error handling for invalid responses from Server. In this case when an open port is used that does not support WebSockets.
Also Changed default ports used when ws(1883 -> 80) or wss(8883 -> 443) uris are used to better match WebSockets standards.

Signed-off-by: James Sutton <james.sutton@uk.ibm.com>

Author: jpwsutton

org.eclipse.paho.client.mqttv3/src/main/java/org/eclipse/paho/client/mqttv3/MqttAsyncClient.java

@@ -411,7 +411,7 @@ else if ((factory instanceof SSLSocketFactory) == false) {
 		case MqttConnectOptions.URI_TYPE_WS:
 			shortAddress = address.substring(5);
 			host = getHostName(shortAddress);
-			port = getPort(shortAddress, 1883);
+			port = getPort(shortAddress, 80);
 			if (factory == null) {
 				factory = SocketFactory.getDefault();
 			}
@@ -424,7 +424,7 @@ else if (factory instanceof SSLSocketFactory) {
 		case MqttConnectOptions.URI_TYPE_WSS:
 			shortAddress = address.substring(6);
 			host = getHostName(shortAddress);
-			port = getPort(shortAddress, 8883);
+			port = getPort(shortAddress, 443);
 			SSLSocketFactoryFactory wSSFactoryFactory = null;
 			if (factory == null) {
 				wSSFactoryFactory = new SSLSocketFactoryFactory();

org.eclipse.paho.client.mqttv3/src/main/java/org/eclipse/paho/client/mqttv3/internal/websocket/WebSocketHandshake.java

@@ -94,6 +94,9 @@ private void receiveHandshakeResponse(String key) throws IOException {
 		BufferedReader in = new BufferedReader(new InputStreamReader(input));
 		ArrayList responseLines = new ArrayList();
 		String line = in.readLine();
+		if(line == null){
+			throw new IOException("WebSocket Response header: Invalid response from Server, It may not support WebSockets.");
+		}
 		while(!line.equals(EMPTY) ) {
 			responseLines.add(line);
 			line = in.readLine();