diff --git a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/SchemalessStatement.java b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/SchemalessStatement.java
index f90fa43fa26288943b5fa6c500ace6b92feb8429..748891d943536b3cb6ebd6adffd295573adee4d1 100644
--- a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/SchemalessStatement.java
+++ b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/SchemalessStatement.java
@@ -8,16 +8,35 @@ import java.sql.Connection;
 import java.sql.SQLException;
 import java.sql.Statement;
 
+/**
+ * @author huolibo@qq.com
+ * @version v1.0.0
+ * @JDK: 1.8
+ * @description: this class is an extension of {@link Statement}. use like:
+ * Statement statement = conn.createStatement();
+ * SchemalessStatement schemalessStatement = new SchemalessStatement(statement);
+ * schemalessStatement.execute(sql);
+ * schemalessStatement.executeSchemaless(lines, SchemalessProtocolType, SchemalessTimestampType);
+ * @since 2021-11-03 17:10
+ */
 public class SchemalessStatement extends AbstractStatementWrapper {
     public SchemalessStatement(Statement statement) {
         super(statement);
     }
 
-    public void executeSchemaless(String[] strings, SchemalessProtocolType protocolType, SchemalessTimestampType timestampType) throws SQLException {
+    /**
+     * batch insert schemaless lines
+     *
+     * @param lines         schemaless data
+     * @param protocolType  schemaless type {@link SchemalessProtocolType}
+     * @param timestampType Time precision {@link SchemalessTimestampType}
+     * @throws SQLException execute insert exception
+     */
+    public void executeSchemaless(String[] lines, SchemalessProtocolType protocolType, SchemalessTimestampType timestampType) throws SQLException {
         Connection connection = this.getConnection();
         if (connection instanceof TSDBConnection) {
             TSDBConnection tsdbConnection = (TSDBConnection) connection;
-            tsdbConnection.getConnector().insertLines(strings, protocolType, timestampType);
+            tsdbConnection.getConnector().insertLines(lines, protocolType, timestampType);
         } else if (connection instanceof RestfulConnection) {
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD, "restful connection is not supported currently");
         } else {
@@ -25,7 +44,15 @@ public class SchemalessStatement extends AbstractStatementWrapper {
         }
     }
 
-    public void executeSchemaless(String sql, SchemalessProtocolType protocolType, SchemalessTimestampType timestampType) throws SQLException {
-        executeSchemaless(new String[]{sql}, protocolType, timestampType);
+    /**
+     * only one insert
+     *
+     * @param line          schemaless line
+     * @param protocolType  schemaless type {@link SchemalessProtocolType}
+     * @param timestampType Time precision {@link SchemalessTimestampType}
+     * @throws SQLException execute insert exception
+     */
+    public void executeSchemaless(String line, SchemalessProtocolType protocolType, SchemalessTimestampType timestampType) throws SQLException {
+        executeSchemaless(new String[]{line}, protocolType, timestampType);
     }
 }
diff --git a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/enums/SchemalessProtocolType.java b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/enums/SchemalessProtocolType.java
index d5bd1bde5eb3d73ebd419652ca1fbbe3485d95c5..2a0bea15702a79b3440f95771cf56b879a814626 100644
--- a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/enums/SchemalessProtocolType.java
+++ b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/enums/SchemalessProtocolType.java
@@ -1,5 +1,7 @@
 package com.taosdata.jdbc.enums;
 
+import java.util.Arrays;
+
 public enum SchemalessProtocolType {
     UNKNOWN,
     LINE,
@@ -7,4 +9,10 @@ public enum SchemalessProtocolType {
     JSON,
     ;
 
+    public static SchemalessProtocolType parse(String type) {
+        return Arrays.stream(SchemalessProtocolType.values())
+                .filter(protocol -> type.equalsIgnoreCase(protocol.name()))
+                .findFirst().orElse(UNKNOWN);
+    }
+
 }
diff --git a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/enums/SchemalessTimestampType.java b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/enums/SchemalessTimestampType.java
index 159714262e5386e00e74bb6154a20165a735c174..fa10a23634ec75182365d42ebfb79aff7b14b08f 100644
--- a/src/connector/jdbc/src/main/java/com/taosdata/jdbc/enums/SchemalessTimestampType.java
+++ b/src/connector/jdbc/src/main/java/com/taosdata/jdbc/enums/SchemalessTimestampType.java
@@ -1,7 +1,7 @@
 package com.taosdata.jdbc.enums;
 
 public enum SchemalessTimestampType {
-
+    // Let the database decide
     NOT_CONFIGURED,
     HOURS,
     MINUTES,
diff --git a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/SchemalessInsertTest.java b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/SchemalessInsertTest.java
index c706704f67e75ce61f6f96def26c6895e8805a7a..fd4ac12ce40dc02f2b6ffbf91e33b0e0bd2398a9 100644
--- a/src/connector/jdbc/src/test/java/com/taosdata/jdbc/SchemalessInsertTest.java
+++ b/src/connector/jdbc/src/test/java/com/taosdata/jdbc/SchemalessInsertTest.java
@@ -1,5 +1,7 @@
 package com.taosdata.jdbc;
 
+import com.alibaba.fastjson.JSONArray;
+import com.alibaba.fastjson.JSONObject;
 import com.taosdata.jdbc.enums.SchemalessProtocolType;
 import com.taosdata.jdbc.enums.SchemalessTimestampType;
 import org.junit.After;
@@ -10,10 +12,14 @@ import org.junit.Test;
 import java.sql.*;
 
 public class SchemalessInsertTest {
-    private String host = "127.0.0.1";
-    private String dbname = "test_schemaless_insert";
+    private final String dbname = "test_schemaless_insert";
     private Connection conn;
 
+    /**
+     * schemaless insert compatible with influxdb
+     *
+     * @throws SQLException execute error
+     */
     @Test
     public void schemalessInsert() throws SQLException {
         // given
@@ -41,6 +47,11 @@ public class SchemalessInsertTest {
         statement.close();
     }
 
+    /**
+     * telnet insert compatible with opentsdb
+     *
+     * @throws SQLException execute error
+     */
     @Test
     public void telnetInsert() throws SQLException {
         // given
@@ -71,6 +82,11 @@ public class SchemalessInsertTest {
         statement.close();
     }
 
+    /**
+     * json insert compatible with opentsdb json format
+     *
+     * @throws SQLException execute error
+     */
     @Test
     public void jsonInsert() throws SQLException {
         // given
@@ -113,13 +129,15 @@ public class SchemalessInsertTest {
         while (rs.next()) {
             rowCnt++;
         }
-//        Assert.assertEquals(json.length, rowCnt);
+
+        Assert.assertEquals(((JSONArray) JSONObject.parse(json)).size(), rowCnt);
         rs.close();
         statement.close();
     }
 
     @Before
     public void before() {
+        String host = "127.0.0.1";
         final String url = "jdbc:TAOS://" + host + ":6030/?user=root&password=taosdata";
         try {
             conn = DriverManager.getConnection(url);