fixed eclipse-paho#418

Signed-off-by: chowen <[email protected]>

Author: ChowenPan

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

@@ -275,11 +275,16 @@ public static boolean isMatched(String topicFilter, String topicName) throws Ill
 		}
 
 		while (filterPos < filterLen && topicPos < topicLen) {
-                        if (topicFilter.charAt(filterPos) == '#')
-                                topicPos = topicLen - 1; // skip until end of string
-
+			if (topicFilter.charAt(filterPos) == '#') {
+				/*
+				 * next 'if' will break when topicFilter = topic/# and topicName topic/A/,
+				 * but they are matched
+				 */
+				topicPos = topicLen;
+				filterPos = filterLen;
+				break;
+			}
 			if (topicName.charAt(topicPos) == '/' && topicFilter.charAt(filterPos) != '/')
-
 				break;
 			if (topicFilter.charAt(filterPos) != '+' && topicFilter.charAt(filterPos) != '#'
 					&& topicFilter.charAt(filterPos) != topicName.charAt(topicPos))
@@ -301,11 +306,11 @@ public static boolean isMatched(String topicFilter, String topicName) throws Ill
 			 * https://github.com/eclipse/paho.mqtt.java/issues/418
 			 * Covers edge case to match sport/# to sport
 			 */
-			if ((topicFilter.length() - topicName.length()) == 2 &&
-					topicFilter.substring(topicFilter.length() -2, topicFilter.length()).equals("/#")) {
-				String filterSub = topicFilter.substring(0, topicFilter.length() - 2);
-				if (filterSub.equals(topicName)) {
-					System.err.println("filterSub equals topicName: " + filterSub + " == " + topicName);
+			if ((topicFilter.length() - filterPos > 0) && (topicPos == topicLen)) {
+				if (topicName.charAt(topicPos - 1) == '/' && topicFilter.charAt(filterPos) == '#')
+					return true;
+				if (topicFilter.length() - filterPos > 1
+						&& topicFilter.substring(filterPos, filterPos + 2).equals("/#")) {
 					return true;
 				}
 			}