Add message String to ConnectionException

smack-core/src/main/java/org/jivesoftware/smack/SmackException.java

@@ -169,10 +169,22 @@ public class SmackException extends Exception {
             failedAddresses = new ArrayList<HostAddress>(0);
         }
 
-        public ConnectionException(List<HostAddress> failedAddresses) {
+        private ConnectionException(String message, List<HostAddress> failedAddresses) {
+            super(message);
             this.failedAddresses = failedAddresses;
         }
 
+        public static ConnectionException from(List<HostAddress> failedAddresses) {
+            StringBuilder sb = new StringBuilder("The following addresses failed: ");
+            for (HostAddress hostAddress : failedAddresses) {
+                sb.append(hostAddress.getErrorMessage());
+                sb.append(", ");
+            }
+            // Remove the last whitespace
+            sb.deleteCharAt(sb.length());
+            return new ConnectionException(sb.toString(), failedAddresses);
+        }
+
         public List<HostAddress> getFailedAddresses() {
             return failedAddresses;
         }

smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java

@@ -592,7 +592,7 @@ public class XMPPTCPConnection extends AbstractXMPPConnection {
                 // There are no more host addresses to try
                 // throw an exception and report all tried
                 // HostAddresses in the exception
-                throw new ConnectionException(failedAddresses);
+                throw ConnectionException.from(failedAddresses);
             }
         }
         socketClosed = false;