(chore) doc for HandleMessageFailedException

Author: ylgrgyq

src/main/java/cn/leancloud/kafka/consumer/HandleMessageFailedException.java

@@ -1,5 +1,11 @@
 package cn.leancloud.kafka.consumer;
 
+import org.apache.kafka.clients.consumer.ConsumerRecord;
+
+/**
+ * Thrown by {@link ConsumerRecordHandler)} when the record handler failed to handle a {@link ConsumerRecord}. The origin
+ * exception will be wrapped in this exception.
+ */
 public final class HandleMessageFailedException extends RuntimeException {
     public HandleMessageFailedException() {
         super();