[ISSUE #1120] Add new feature: support namespace

example/src/main/java/org/apache/rocketmq/example/namespace/ProducerWithNamespace.java

@@ -30,7 +30,7 @@ public class ProducerWithNamespace {
             Message message = new Message("topicTest", "tagTest", "Hello world".getBytes());
             try {
                 SendResult result = producer.send(message);
-                System.out.println("Topic:" + message.getTopic() + " send success, msgId is:" + result.getMsgId());
+                System.out.printf("Topic:%s send success, misId is:%s%n", message.getTopic(), result.getMsgId());
             } catch (Exception e) {
                 e.printStackTrace();
             }

example/src/main/java/org/apache/rocketmq/example/namespace/PullConsumerWithNamespace.java

@@ -79,7 +79,7 @@ public class PullConsumerWithNamespace {
             return;
         }
         pullResult.getMsgFoundList().stream().forEach(
-            (msg) -> System.out.println("Topic is:" + msg.getTopic() + "msgId is:" + msg.getMsgId()));
+            (msg) -> System.out.printf("Topic is:%s, msgId is:%s%n" , msg.getTopic(), msg.getMsgId()));
     }
 
     private static void putMessageQueueOffset(MessageQueue mq, long offset) {

example/src/main/java/org/apache/rocketmq/example/namespace/PushConsumerWithNamespace.java

@@ -27,9 +27,9 @@ public class PushConsumerWithNamespace {
         defaultMQPushConsumer.subscribe("topicTest", "*");
         defaultMQPushConsumer.registerMessageListener((MessageListenerConcurrently)(msgs, context) -> {
             msgs.stream().forEach((msg) -> {
-                System.out.println("Msg topic is:" + msg.getTopic() + " MsgId is:" + msg.getMsgId());
+                System.out.printf("Msg topic is:%s, MsgId is:%s, reconsumeTimes is:%s%n", msg.getTopic() , msg.getMsgId(), msg.getReconsumeTimes());
             });
-            return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
+            return ConsumeConcurrentlyStatus.RECONSUME_LATER;
         });
 
         defaultMQPushConsumer.start();