mod java exception

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

@@ -27,6 +27,10 @@ public static void main(String[] args) throws SQLException {
     } catch (SQLException ex) {
         // handle any errors, please refer to the JDBC specifications for detailed exceptions info
         System.out.println("Failed to connect to " + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+        throw ex;
+    } catch (Exception ex){
+        System.out.println("Failed to connect to " + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+        throw ex;
     }
 }
 // ANCHOR_END: main

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

@@ -16,6 +16,10 @@ public static void main(String[] args) throws SQLException {
     } catch (SQLException ex) {
         // handle any errors, please refer to the JDBC specifications for detailed exceptions info
         System.out.println("Failed to connect to " + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+        throw ex;
+    } catch (Exception ex){
+        System.out.println("Failed to connect to " + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+        throw ex;
     }
 }
 // ANCHOR_END: main

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

@@ -28,6 +28,10 @@ public static void main(String[] args) throws SQLException {
     } catch (SQLException ex) {
         // handle any errors, please refer to the JDBC specifications for detailed exceptions info
         System.out.println("Failed to connect to " + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+        throw ex;
+    } catch (Exception ex){
+        System.out.println("Failed to connect to " + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+        throw ex;
     }
 }
 // ANCHOR_END: main

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/ConsumerLoopFull.java

@@ -16,6 +16,8 @@ public class ConsumerLoopFull {
     static private Connection connection;
     static private Statement statement;
 
+    static private volatile boolean stopFlag = false;
+
     public static TaosConsumer<ResultBean> getConsumer() throws SQLException {
 // ANCHOR: create_consumer
         Properties config = new Properties();
@@ -38,15 +40,16 @@ public class ConsumerLoopFull {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to create jni consumer, host : " + config.getProperty("bootstrap.servers") + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to create consumer", ex);
-        } catch (Exception e) {
+        } catch (Exception ex) {
-            e.printStackTrace();
+            System.out.println("Failed to create jni consumer, host : " + config.getProperty("bootstrap.servers")
-            throw new SQLException("Failed to create consumer", e);
+                    + "; ErrMessage: " + ex.getMessage());
+            throw new SQLException("Failed to create consumer", ex);
         }
 // ANCHOR_END: create_consumer
     }
 
-    public static void pollDataExample() throws SQLException {
+    public static void pollDataExample(TaosConsumer<ResultBean> consumer) throws SQLException {
-        try (TaosConsumer<ResultBean> consumer = getConsumer()) {
+        try{
             // subscribe to the topics
             List<String> topics = Collections.singletonList("topic_meters");
 
@@ -68,12 +71,15 @@ public class ConsumerLoopFull {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to poll data from topic_meters, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to poll data from topic_meters", ex);
+        } catch (Exception ex) {
+            System.out.println("Failed to poll data from topic_meters; ErrMessage: " + ex.getMessage());
+            throw new SQLException("Failed to poll data from topic_meters", ex);
         }
     }
 
-    public static void pollExample() throws SQLException {
+    public static void pollExample(TaosConsumer<ResultBean> consumer) throws SQLException {
 // ANCHOR: poll_data_code_piece
-        try (TaosConsumer<ResultBean> consumer = getConsumer()) {
+        try {
             List<String> topics = Collections.singletonList("topic_meters");
 
             // subscribe to the topics
@@ -93,54 +99,48 @@ public class ConsumerLoopFull {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to poll data; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to poll data", ex);
+        } catch (Exception ex) {
+            System.out.println("Failed to poll data; ErrMessage: " + ex.getMessage());
+            throw new SQLException("Failed to poll data", ex);
         }
 // ANCHOR_END: poll_data_code_piece
     }
 
-    public static void seekExample() throws SQLException {
+    public static void seekExample(TaosConsumer<ResultBean> consumer) throws SQLException {
 // ANCHOR: consumer_seek
-        try (TaosConsumer<ResultBean> consumer = getConsumer()) {
+        try {
             List<String> topics = Collections.singletonList("topic_meters");
 
             // subscribe to the topics
             consumer.subscribe(topics);
             System.out.println("subscribe topics successfully");
+            Set<TopicPartition> assignment = consumer.assignment();
+            System.out.println("now assignment: " + JSON.toJSONString(assignment));
+
             ConsumerRecords<ResultBean> records = ConsumerRecords.emptyRecord();
             // make sure we have got some data
             while (records.isEmpty()) {
                 records = consumer.poll(Duration.ofMillis(100));
             }
 
-            for (ConsumerRecord<ResultBean> record : records) {
-                System.out.println("first data polled: " + JSON.toJSONString(record.value()));
-                Set<TopicPartition> assignment = consumer.assignment();
-                // seek to the beginning of the all partitions
             consumer.seekToBeginning(assignment);
             System.out.println("assignment seek to beginning successfully");
-                break;
+            System.out.println("beginning assignment: " + JSON.toJSONString(assignment));
-            }
-
-            // poll data again
-            records = consumer.poll(Duration.ofMillis(100));
-            for (ConsumerRecord<ResultBean> record : records) {
-                // process the data here
-                System.out.println("second data polled: " + JSON.toJSONString(record.value()));
-                break;
-            }
-
-
         } catch (SQLException ex) {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("seek example failed; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("seek example failed", ex);
+        } catch (Exception ex) {
+            System.out.println("seek example failed; ErrMessage: " + ex.getMessage());
+            throw new SQLException("seek example failed", ex);
         }
 // ANCHOR_END: consumer_seek
     }
 
 
-    public static void commitExample() throws SQLException {
+    public static void commitExample(TaosConsumer<ResultBean> consumer) throws SQLException {
 // ANCHOR: commit_code_piece
-        try (TaosConsumer<ResultBean> consumer = getConsumer()) {
+        try {
             List<String> topics = Collections.singletonList("topic_meters");
 
             consumer.subscribe(topics);
@@ -160,12 +160,14 @@ public class ConsumerLoopFull {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to execute consumer functions. ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to execute consumer functions", ex);
+        } catch (Exception ex) {
+            System.out.println("Failed to execute consumer functions. ErrMessage: " + ex.getMessage());
+            throw new SQLException("Failed to execute consumer functions", ex);
         }
 // ANCHOR_END: commit_code_piece
     }
 
-    public static void unsubscribeExample() throws SQLException {
+    public static void unsubscribeExample(TaosConsumer<ResultBean> consumer) throws SQLException {
-        TaosConsumer<ResultBean> consumer = getConsumer();
         List<String> topics = Collections.singletonList("topic_meters");
         consumer.subscribe(topics);
 // ANCHOR: unsubscribe_data_code_piece
@@ -175,7 +177,11 @@ public class ConsumerLoopFull {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to unsubscribe consumer. ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to unsubscribe consumer", ex);
-        } finally {
+        } catch (Exception ex) {
+            System.out.println("Failed to unsubscribe consumer. ErrMessage: " + ex.getMessage());
+            throw new SQLException("Failed to unsubscribe consumer", ex);
+        }
+        finally {
             consumer.close();
         }
 // ANCHOR_END: unsubscribe_data_code_piece
@@ -243,17 +249,16 @@ public class ConsumerLoopFull {
         }
     }
 
-    public static void prepareData() throws SQLException {
+    public static void prepareData() throws SQLException, InterruptedException {
-        StringBuilder insertQuery = new StringBuilder();
-        insertQuery.append("INSERT INTO " +
-                "power.d1001 USING power.meters TAGS(2,'California.SanFrancisco') " +
-                "VALUES ");
-        for (int i = 0; i < 10000; i++) {
-            insertQuery.append("(NOW + ").append(i).append("a, 10.30000, 219, 0.31000) ");
-        }
         try {
-            int affectedRows = statement.executeUpdate(insertQuery.toString());
+            int i = 0;
-            assert affectedRows == 10000;
+            while (!stopFlag) {
+                i++;
+                String insertQuery = "INSERT INTO power.d1001 USING power.meters TAGS(2,'California.SanFrancisco') VALUES (NOW + " + i + "a, 10.30000, 219, 0.31000) ";
+                int affectedRows = statement.executeUpdate(insertQuery);
+                assert affectedRows == 1;
+                Thread.sleep(1);
+            }
         } catch (SQLException ex) {
             System.out.println("Failed to insert data to power.meters, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to insert data to power.meters", ex);
@@ -315,7 +320,7 @@ public class ConsumerLoopFull {
     }
 
 
-    public static void main(String[] args) throws SQLException {
+    public static void main(String[] args) throws SQLException, InterruptedException {
         initConnection();
         prepareMeta();
 
@@ -326,11 +331,14 @@ public class ConsumerLoopFull {
         executor.submit(() -> {
             try {
                 // please use one example at a time
-                pollDataExample();
+                TaosConsumer<ResultBean> consumer = getConsumer();
-//                seekExample();
+
-//                pollExample();
+                pollDataExample(consumer);
-//                commitExample();
+                seekExample(consumer);
-                unsubscribeExample();
+                pollExample(consumer);
+                commitExample(consumer);
+                unsubscribeExample(consumer);
+                stopFlag = true;
             } catch (SQLException ex) {
                 System.out.println("Failed to poll data from topic_meters, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             }

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/JdbcCreatDBDemo.java

@@ -45,6 +45,10 @@ public class JdbcCreatDBDemo {
         } catch (SQLException ex) {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to create db and table, url:" + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+            throw ex;
+        } catch (Exception ex){
+            System.out.println("Failed to create db and table, url:" + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+            throw ex;
         }
 // ANCHOR_END: create_db_and_table
 

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/JdbcInsertDataDemo.java

@@ -43,7 +43,10 @@ public class JdbcInsertDataDemo {
         } catch (SQLException ex) {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to insert data to power.meters, url:" + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-
+            throw ex;
+        } catch (Exception ex){
+            System.out.println("Failed to insert data to power.meters, url:" + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+            throw ex;
         }
 // ANCHOR_END: insert_data
     }

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/JdbcQueryDemo.java

@@ -44,6 +44,10 @@ public class JdbcQueryDemo {
         } catch (SQLException ex) {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to query data from power.meters, url:" + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+            throw ex;
+        } catch (Exception ex){
+            System.out.println("Failed to query data from power.meters, url:" + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+            throw ex;
         }
 // ANCHOR_END: query_data
     }

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/JdbcReqIdDemo.java

@@ -38,7 +38,10 @@ public class JdbcReqIdDemo {
         } catch (SQLException ex) {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to execute sql with reqId, url:" + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-
+            throw ex;
+        } catch (Exception ex){
+            System.out.println("Failed to execute sql with reqId, url:" + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+            throw ex;
         }
 // ANCHOR_END: with_reqid
     }

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/ParameterBindingBasicDemo.java

@@ -69,6 +69,10 @@ public class ParameterBindingBasicDemo {
         } catch (SQLException ex) {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to insert to table meters using stmt, url: " + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+            throw ex;
+        } catch (Exception ex){
+            System.out.println("Failed to insert to table meters using stmt, url: " + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+            throw ex;
         }
     }
 

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/ParameterBindingFullDemo.java

@@ -31,7 +31,7 @@ public class ParameterBindingFullDemo {
     public static void main(String[] args) throws SQLException {
 
         String jdbcUrl = "jdbc:TAOS://" + host + ":6030/";
-        Connection conn = DriverManager.getConnection(jdbcUrl, "root", "taosdata");
+        try (Connection conn = DriverManager.getConnection(jdbcUrl, "root", "taosdata")) {
 
             init(conn);
 
@@ -44,7 +44,14 @@ public class ParameterBindingFullDemo {
             bindGeometry(conn);
 
             clean(conn);
-        conn.close();
+        } catch (SQLException ex) {
+            // handle any errors, please refer to the JDBC specifications for detailed exceptions info
+            System.out.println("Failed to insert to table meters using stmt, url: " + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+            throw ex;
+        } catch (Exception ex){
+            System.out.println("Failed to insert to table meters using stmt, url: " + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+            throw ex;
+        }
     }
 
     private static void init(Connection conn) throws SQLException {

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/SchemalessJniTest.java

@@ -28,6 +28,10 @@ public class SchemalessJniTest {
         } catch (SQLException ex) {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to insert data with schemaless, host:" + host + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+            throw ex;
+        } catch (Exception ex){
+            System.out.println("Failed to insert data with schemaless, host:" + host + "; ErrMessage: " + ex.getMessage());
+            throw ex;
         }
     }
 

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/SchemalessWsTest.java

@@ -28,6 +28,10 @@ public class SchemalessWsTest {
         } catch (SQLException ex) {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to insert data with schemaless, host:" + host + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+            throw ex;
+        } catch (Exception ex){
+            System.out.println("Failed to insert data with schemaless, host:" + host + "; ErrMessage: " + ex.getMessage());
+            throw ex;
         }
     }
 

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/WSParameterBindingBasicDemo.java

@@ -50,6 +50,10 @@ public class WSParameterBindingBasicDemo {
         } catch (SQLException ex) {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
             System.out.println("Failed to insert to table meters using stmt, url: " + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+            throw ex;
+        } catch (Exception ex){
+            System.out.println("Failed to insert to table meters using stmt, url: " + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+            throw ex;
         }
     }
 

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/WSParameterBindingFullDemo.java

@@ -39,8 +39,11 @@ public class WSParameterBindingFullDemo {
 
         } catch (SQLException ex) {
             // handle any errors, please refer to the JDBC specifications for detailed exceptions info
-            System.out.println("Error Code: " + ex.getErrorCode());
+            System.out.println("Failed to insert to table meters using stmt, url: " + jdbcUrl + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-            System.out.println("Message: " + ex.getMessage());
+            throw ex;
+        } catch (Exception ex){
+            System.out.println("Failed to insert to table meters using stmt, url: " + jdbcUrl + "; ErrMessage: " + ex.getMessage());
+            throw ex;
         }
     }
 

examples/JDBC/JDBCDemo/src/main/java/com/taosdata/example/WsConsumerLoopFull.java

@@ -6,10 +6,7 @@ import com.taosdata.jdbc.tmq.*;
 
 import java.sql.*;
 import java.time.Duration;
-import java.util.Collections;
+import java.util.*;
-import java.util.List;
-import java.util.Properties;
-import java.util.Set;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
@@ -29,7 +26,7 @@ public class WsConsumerLoopFull {
         config.setProperty("enable.auto.commit", "true");
         config.setProperty("auto.commit.interval.ms", "1000");
         config.setProperty("group.id", "group1");
-        config.setProperty("client.id", "client1");
+        config.setProperty("client.id", "1");
         config.setProperty("td.connect.user", "root");
         config.setProperty("td.connect.pass", "taosdata");
         config.setProperty("value.deserializer", "com.taosdata.example.WsConsumerLoopFull$ResultDeserializer");
@@ -38,20 +35,19 @@ public class WsConsumerLoopFull {
         try {
             return new TaosConsumer<>(config);
         } catch (SQLException ex) {
-            // handle any errors, please refer to the JDBC specifications for detailed
+            // handle any errors, please refer to the JDBC specifications for detailed exceptions info
-            // exceptions info
+            System.out.println("Failed to create websocket consumer, host : " + config.getProperty("bootstrap.servers") + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-            System.out.println("Failed to create websocket consumer, host : " + config.getProperty("bootstrap.servers")
+            throw new SQLException("Failed to create consumer", ex);
-                    + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+        } catch (Exception ex) {
+            System.out.println("Failed to create websocket consumer, host : " + config.getProperty("bootstrap.servers")
+                    + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to create consumer", ex);
-        } catch (Exception e) {
-            e.printStackTrace();
-            throw new SQLException("Failed to create consumer", e);
         }
 // ANCHOR_END: create_consumer
     }
 
-    public static void pollDataExample() throws SQLException {
+    public static void pollDataExample(TaosConsumer<ResultBean> consumer) throws SQLException {
-        try (TaosConsumer<ResultBean> consumer = getConsumer()) {
+        try{
             // subscribe to the topics
             List<String> topics = Collections.singletonList("topic_meters");
 
@@ -70,17 +66,18 @@ public class WsConsumerLoopFull {
             consumer.unsubscribe();
             System.out.println("unsubscribed topics successfully");
         } catch (SQLException ex) {
-            // handle any errors, please refer to the JDBC specifications for detailed
+            // handle any errors, please refer to the JDBC specifications for detailed exceptions info
-            // exceptions info
+            System.out.println("Failed to poll data from topic_meters, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-            System.out.println("Failed to poll data from topic_meters, ErrCode:" + ex.getErrorCode() + "; ErrMessage: "
+            throw new SQLException("Failed to poll data from topic_meters", ex);
-                    + ex.getMessage());
+        } catch (Exception ex) {
+            System.out.println("Failed to poll data from topic_meters; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to poll data from topic_meters", ex);
         }
     }
 
-    public static void pollExample() throws SQLException {
+    public static void pollExample(TaosConsumer<ResultBean> consumer) throws SQLException {
 // ANCHOR: poll_data_code_piece
-        try (TaosConsumer<ResultBean> consumer = getConsumer()) {
+        try {
             List<String> topics = Collections.singletonList("topic_meters");
 
             // subscribe to the topics
@@ -97,58 +94,51 @@ public class WsConsumerLoopFull {
             }
 
         } catch (SQLException ex) {
-            // handle any errors, please refer to the JDBC specifications for detailed
+            // handle any errors, please refer to the JDBC specifications for detailed exceptions info
-            // exceptions info
+            System.out.println("Failed to poll data; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-            System.out
+            throw new SQLException("Failed to poll data", ex);
-                    .println("Failed to poll data; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+        } catch (Exception ex) {
+            System.out.println("Failed to poll data; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to poll data", ex);
         }
 // ANCHOR_END: poll_data_code_piece
     }
 
-    public static void seekExample() throws SQLException {
+    public static void seekExample(TaosConsumer<ResultBean> consumer) throws SQLException {
 // ANCHOR: consumer_seek
-        try (TaosConsumer<ResultBean> consumer = getConsumer()) {
+        try {
             List<String> topics = Collections.singletonList("topic_meters");
 
             // subscribe to the topics
             consumer.subscribe(topics);
             System.out.println("subscribe topics successfully");
+            Set<TopicPartition> assignment = consumer.assignment();
+            System.out.println("now assignment: " + JSON.toJSONString(assignment));
+
             ConsumerRecords<ResultBean> records = ConsumerRecords.emptyRecord();
             // make sure we have got some data
             while (records.isEmpty()) {
                 records = consumer.poll(Duration.ofMillis(100));
             }
 
-            for (ConsumerRecord<ResultBean> record : records) {
-                System.out.println("first data polled: " + JSON.toJSONString(record.value()));
-                Set<TopicPartition> assignment = consumer.assignment();
-                // seek to the beginning of the all partitions
             consumer.seekToBeginning(assignment);
             System.out.println("assignment seek to beginning successfully");
-                break;
+            System.out.println("beginning assignment: " + JSON.toJSONString(assignment));
-            }
-
-            // poll data again
-            records = consumer.poll(Duration.ofMillis(100));
-            for (ConsumerRecord<ResultBean> record : records) {
-                // process the data here
-                System.out.println("second data polled: " + JSON.toJSONString(record.value()));
-                break;
-            }
         } catch (SQLException ex) {
-            // handle any errors, please refer to the JDBC specifications for detailed
+            // handle any errors, please refer to the JDBC specifications for detailed exceptions info
-            // exceptions info
+            System.out.println("seek example failed; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-            System.out
+            throw new SQLException("seek example failed", ex);
-                    .println("seek example failed; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
+        } catch (Exception ex) {
+            System.out.println("seek example failed; ErrMessage: " + ex.getMessage());
             throw new SQLException("seek example failed", ex);
         }
 // ANCHOR_END: consumer_seek
     }
 
-    public static void commitExample() throws SQLException {
+
+    public static void commitExample(TaosConsumer<ResultBean> consumer) throws SQLException {
 // ANCHOR: commit_code_piece
-        try (TaosConsumer<ResultBean> consumer = getConsumer()) {
+        try {
             List<String> topics = Collections.singletonList("topic_meters");
 
             consumer.subscribe(topics);
@@ -165,29 +155,31 @@ public class WsConsumerLoopFull {
                 }
             }
         } catch (SQLException ex) {
-            // handle any errors, please refer to the JDBC specifications for detailed
+            // handle any errors, please refer to the JDBC specifications for detailed exceptions info
-            // exceptions info
+            System.out.println("Failed to execute consumer functions. ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-            System.out.println("Failed to execute consumer functions. ErrCode:" + ex.getErrorCode() + "; ErrMessage: "
+            throw new SQLException("Failed to execute consumer functions", ex);
-                    + ex.getMessage());
+        } catch (Exception ex) {
+            System.out.println("Failed to execute consumer functions. ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to execute consumer functions", ex);
         }
 // ANCHOR_END: commit_code_piece
     }
 
-    public static void unsubscribeExample() throws SQLException {
+    public static void unsubscribeExample(TaosConsumer<ResultBean> consumer) throws SQLException {
-        TaosConsumer<ResultBean> consumer = getConsumer();
         List<String> topics = Collections.singletonList("topic_meters");
         consumer.subscribe(topics);
 // ANCHOR: unsubscribe_data_code_piece
         try {
             consumer.unsubscribe();
         } catch (SQLException ex) {
-            // handle any errors, please refer to the JDBC specifications for detailed
+            // handle any errors, please refer to the JDBC specifications for detailed exceptions info
-            // exceptions info
+            System.out.println("Failed to unsubscribe consumer. ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-            System.out.println("Failed to unsubscribe consumer. ErrCode:" + ex.getErrorCode() + "; ErrMessage: "
-                    + ex.getMessage());
             throw new SQLException("Failed to unsubscribe consumer", ex);
-        } finally {
+        } catch (Exception ex) {
+            System.out.println("Failed to unsubscribe consumer. ErrMessage: " + ex.getMessage());
+            throw new SQLException("Failed to unsubscribe consumer", ex);
+        }
+        finally {
             consumer.close();
         }
 // ANCHOR_END: unsubscribe_data_code_piece
@@ -255,20 +247,16 @@ public class WsConsumerLoopFull {
         }
     }
 
-    public static void prepareData() throws SQLException {
+    public static void prepareData() throws SQLException, InterruptedException {
-        StringBuilder insertQuery = new StringBuilder();
-        insertQuery.append("INSERT INTO " +
-                "power.d1001 USING power.meters TAGS(2,'California.SanFrancisco') " +
-                "VALUES ");
-        for (int i = 0; i < 10000; i++) {
-            insertQuery.append("(NOW + ").append(i).append("a, 10.30000, 219, 0.31000) ");
-        }
         try {
-            int affectedRows = statement.executeUpdate(insertQuery.toString());
+            for (int i = 0; i < 3000; i++) {
-            assert affectedRows == 10000;
+                String insertQuery = "INSERT INTO power.d1001 USING power.meters TAGS(2,'California.SanFrancisco') VALUES (NOW + " + i + "a, 10.30000, 219, 0.31000) ";
+                int affectedRows = statement.executeUpdate(insertQuery);
+                assert affectedRows == 1;
+                Thread.sleep(1);
+            }
         } catch (SQLException ex) {
-            System.out.println("Failed to insert data to power.meters, ErrCode:" + ex.getErrorCode() + "; ErrMessage: "
+            System.out.println("Failed to insert data to power.meters, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-                    + ex.getMessage());
             throw new SQLException("Failed to insert data to power.meters", ex);
         }
     }
@@ -277,13 +265,10 @@ public class WsConsumerLoopFull {
         try {
             statement.executeUpdate("CREATE DATABASE IF NOT EXISTS power");
             statement.executeUpdate("USE power");
-            statement.executeUpdate(
+            statement.executeUpdate("CREATE STABLE IF NOT EXISTS meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (groupId INT, location BINARY(24))");
-                    "CREATE STABLE IF NOT EXISTS meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (groupId INT, location BINARY(24))");
+            statement.executeUpdate("CREATE TOPIC IF NOT EXISTS topic_meters AS SELECT ts, current, voltage, phase, groupid, location FROM meters");
-            statement.executeUpdate(
-                    "CREATE TOPIC IF NOT EXISTS topic_meters AS SELECT ts, current, voltage, phase, groupid, location FROM meters");
         } catch (SQLException ex) {
-            System.out.println(
+            System.out.println("Failed to create db and table, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-                    "Failed to create db and table, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to create db and table", ex);
         }
     }
@@ -297,15 +282,13 @@ public class WsConsumerLoopFull {
         try {
             connection = DriverManager.getConnection(url, properties);
         } catch (SQLException ex) {
-            System.out.println("Failed to create connection, url:" + url + "; ErrCode:" + ex.getErrorCode()
+            System.out.println("Failed to create connection, url:" + url + "; ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-                    + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to create connection", ex);
         }
         try {
             statement = connection.createStatement();
         } catch (SQLException ex) {
-            System.out.println(
+            System.out.println("Failed to create statement, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-                    "Failed to create statement, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to create statement", ex);
         }
         System.out.println("Connection created successfully.");
@@ -317,8 +300,7 @@ public class WsConsumerLoopFull {
                 statement.close();
             }
         } catch (SQLException ex) {
-            System.out.println(
+            System.out.println("Failed to close statement, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-                    "Failed to close statement, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to close statement", ex);
         }
 
@@ -327,14 +309,14 @@ public class WsConsumerLoopFull {
                 connection.close();
             }
         } catch (SQLException ex) {
-            System.out.println(
+            System.out.println("Failed to close connection, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-                    "Failed to close connection, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
             throw new SQLException("Failed to close connection", ex);
         }
         System.out.println("Connection closed Successfully.");
     }
 
-    public static void main(String[] args) throws SQLException {
+
+    public static void main(String[] args) throws SQLException, InterruptedException {
         initConnection();
         prepareMeta();
 
@@ -345,14 +327,22 @@ public class WsConsumerLoopFull {
         executor.submit(() -> {
             try {
                 // please use one example at a time
-                pollDataExample();
+                TaosConsumer<ResultBean> consumer = getConsumer();
-                // seekExample();
+
-                // pollExample();
+                pollDataExample(consumer);
-                // commitExample();
+                seekExample(consumer);
-                unsubscribeExample();
+                consumer.unsubscribe();
+                pollExample(consumer);
+                consumer.unsubscribe();
+                commitExample(consumer);
+                consumer.unsubscribe();
+                unsubscribeExample(consumer);
             } catch (SQLException ex) {
-                System.out.println("Failed to poll data from topic_meters, ErrCode:" + ex.getErrorCode()
+                System.out.println("Failed to poll data from topic_meters, ErrCode:" + ex.getErrorCode() + "; ErrMessage: " + ex.getMessage());
-                        + "; ErrMessage: " + ex.getMessage());
+                return;
+            } catch (Exception ex) {
+                System.out.println("Failed to poll data from topic_meters, ErrMessage: " + ex.getMessage());
+                return;
             }
             System.out.println("pollDataExample executed successfully");
         });