docs(driver): jdbc 3.2.1 document and error code

docs/examples/java/pom.xml

@@ -22,7 +22,7 @@
     <dependency>
       <groupId>com.taosdata.jdbc</groupId>
       <artifactId>taos-jdbcdriver</artifactId>
-      <version>3.1.0</version>
+      <version>3.2.1</version>
     </dependency>
     <!--    ANCHOR_END: dep-->
     <dependency>

docs/examples/java/src/main/java/com/taos/example/SubscribeDemo.java

 package com.taos.example;
 
+import com.taosdata.jdbc.tmq.ConsumerRecord;
 import com.taosdata.jdbc.tmq.ConsumerRecords;
 import com.taosdata.jdbc.tmq.TMQConstants;
 import com.taosdata.jdbc.tmq.TaosConsumer;
@@ -64,7 +65,8 @@ public class SubscribeDemo {
                 consumer.subscribe(Collections.singletonList(TOPIC));
                 while (!shutdown.get()) {
                     ConsumerRecords<Meters> meters = consumer.poll(Duration.ofMillis(100));
-                    for (Meters meter : meters) {
+                    for (ConsumerRecord<Meters> recode : meters) {
+                        Meters meter = recode.value();
                         System.out.println(meter);
                     }
                 }