Feature/td 5432 (#6963)

* [TD-5342]<feature>: change fastjson and guava version, add retryHandle in HttpClientPoolUtil

* fix some simple problems

src/connector/jdbc/pom.xml

@@ -37,13 +37,6 @@
         <maven.test.jvmargs></maven.test.jvmargs>
     </properties>
     <dependencies>
-        <dependency>
-            <groupId>junit</groupId>
-            <artifactId>junit</artifactId>
-            <version>4.13.1</version>
-            <scope>test</scope>
-        </dependency>
-        <!-- for restful -->
         <dependency>
             <groupId>org.apache.httpcomponents</groupId>
             <artifactId>httpclient</artifactId>
@@ -52,12 +45,18 @@
         <dependency>
             <groupId>com.alibaba</groupId>
             <artifactId>fastjson</artifactId>
-            <version>1.2.58</version>
+            <version>1.2.76</version>
         </dependency>
         <dependency>
             <groupId>com.google.guava</groupId>
             <artifactId>guava</artifactId>
-            <version>30.0-jre</version>
+            <version>30.1.1-jre</version>
+        </dependency>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13.1</version>
+            <scope>test</scope>
         </dependency>
     </dependencies>
 

src/connector/jdbc/src/main/java/com/taosdata/jdbc/AbstractConnection.java

@@ -171,11 +171,7 @@ public abstract class AbstractConnection extends WrapperImpl implements Connecti
         // do nothing
     }
 
-    @Override
-    public Statement createStatement(int resultSetType, int resultSetConcurrency) throws SQLException {
-        if (isClosed())
-            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_CONNECTION_CLOSED);
-
+    private void checkResultSetTypeAndResultSetConcurrency(int resultSetType, int resultSetConcurrency) throws SQLException {
         switch (resultSetType) {
             case ResultSet.TYPE_FORWARD_ONLY:
                 break;
@@ -194,7 +190,14 @@ public abstract class AbstractConnection extends WrapperImpl implements Connecti
             default:
                 throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_INVALID_VARIABLE);
         }
+    }
 
+    @Override
+    public Statement createStatement(int resultSetType, int resultSetConcurrency) throws SQLException {
+        if (isClosed())
+            throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_CONNECTION_CLOSED);
+
+        checkResultSetTypeAndResultSetConcurrency(resultSetType, resultSetConcurrency);
         return createStatement();
     }
 
@@ -203,24 +206,7 @@ public abstract class AbstractConnection extends WrapperImpl implements Connecti
         if (isClosed())
             throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_CONNECTION_CLOSED);
 
-        switch (resultSetType) {
-            case ResultSet.TYPE_FORWARD_ONLY:
-                break;
-            case ResultSet.TYPE_SCROLL_INSENSITIVE:
-            case ResultSet.TYPE_SCROLL_SENSITIVE:
-                throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-            default:
-                throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_INVALID_VARIABLE);
-        }
-
-        switch (resultSetConcurrency) {
-            case ResultSet.CONCUR_READ_ONLY:
-                break;
-            case ResultSet.CONCUR_UPDATABLE:
-                throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_UNSUPPORTED_METHOD);
-            default:
-                throw TSDBError.createSQLException(TSDBErrorNumbers.ERROR_INVALID_VARIABLE);
-        }
+        checkResultSetTypeAndResultSetConcurrency(resultSetType, resultSetConcurrency);
         return prepareStatement(sql);
     }
 

src/connector/jdbc/src/main/java/com/taosdata/jdbc/EmptyResultSet.java

@@ -326,7 +326,7 @@ public class EmptyResultSet implements ResultSet {
 
     @Override
     public int getFetchDirection() throws SQLException {
-        return 0;
+        return ResultSet.FETCH_FORWARD;
     }
 
     @Override
@@ -341,12 +341,12 @@ public class EmptyResultSet implements ResultSet {
 
     @Override
     public int getType() throws SQLException {
-        return 0;
+        return ResultSet.TYPE_FORWARD_ONLY;
     }
 
     @Override
     public int getConcurrency() throws SQLException {
-        return 0;
+        return ResultSet.CONCUR_READ_ONLY;
     }
 
     @Override
@@ -746,7 +746,7 @@ public class EmptyResultSet implements ResultSet {
 
     @Override
     public int getHoldability() throws SQLException {
-        return 0;
+        return ResultSet.CLOSE_CURSORS_AT_COMMIT;
     }
 
     @Override

src/connector/jdbc/src/main/java/com/taosdata/jdbc/TSDBErrorNumbers.java

@@ -40,7 +40,7 @@ public class TSDBErrorNumbers {
     public static final int ERROR_JNI_FETCH_END = 0x2358;       // fetch to the end of resultSet
     public static final int ERROR_JNI_OUT_OF_MEMORY = 0x2359;   // JNI alloc memory failed
 
-    private static final Set<Integer> errorNumbers = new HashSet();
+    private static final Set<Integer> errorNumbers = new HashSet<>();
 
     static {
         errorNumbers.add(ERROR_CONNECTION_CLOSED);

src/connector/jdbc/src/main/java/com/taosdata/jdbc/rs/RestfulResultSet.java

@@ -61,7 +61,7 @@ public class RestfulResultSet extends AbstractResultSet implements ResultSet {
             return;
         // parse row data
         for (int rowIndex = 0; rowIndex < data.size(); rowIndex++) {
-            List<Object> row = new ArrayList();
+            List<Object> row = new ArrayList<>();
             JSONArray jsonRow = data.getJSONArray(rowIndex);
             for (int colIndex = 0; colIndex < this.metaData.getColumnCount(); colIndex++) {
                 row.add(parseColumnData(jsonRow, colIndex, columns.get(colIndex).taos_type));

src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/HttpClientPoolUtil.java

@@ -9,6 +9,7 @@ import org.apache.http.client.protocol.HttpClientContext;
 import org.apache.http.conn.ConnectionKeepAliveStrategy;
 import org.apache.http.entity.StringEntity;
 import org.apache.http.impl.client.CloseableHttpClient;
+import org.apache.http.impl.client.DefaultHttpRequestRetryHandler;
 import org.apache.http.impl.client.HttpClients;
 import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
 import org.apache.http.message.BasicHeaderElementIterator;
@@ -34,7 +35,11 @@ public class HttpClientPoolUtil {
             PoolingHttpClientConnectionManager connectionManager = new PoolingHttpClientConnectionManager();
             connectionManager.setDefaultMaxPerRoute(DEFAULT_MAX_PER_ROUTE);
             connectionManager.setMaxTotal(DEFAULT_MAX_TOTAL);
-            httpClient = HttpClients.custom().setKeepAliveStrategy(DEFAULT_KEEP_ALIVE_STRATEGY).setConnectionManager(connectionManager).build();
+            httpClient = HttpClients.custom()
+                    .setKeepAliveStrategy(DEFAULT_KEEP_ALIVE_STRATEGY)
+                    .setConnectionManager(connectionManager)
+                    .setRetryHandler(new DefaultHttpRequestRetryHandler(3, true))
+                    .build();
         }
     }
 

src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/OSUtils.java

@@ -4,14 +4,14 @@ public class OSUtils {
     private static final String OS = System.getProperty("os.name").toLowerCase();
 
     public static boolean isWindows() {
-        return OS.indexOf("win") >= 0;
+        return OS.contains("win");
     }
 
     public static boolean isMac() {
-        return OS.indexOf("mac") >= 0;
+        return OS.contains("mac");
     }
 
     public static boolean isLinux() {
-        return OS.indexOf("nux") >= 0;
+        return OS.contains("nux");
     }
 }

src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/SqlSyntaxValidator.java

@@ -16,7 +16,7 @@ package com.taosdata.jdbc.utils;
 
 public class SqlSyntaxValidator {
 
-    private static final String[] SQL = {"select", "insert", "import", "create", "use", "alter", "drop", "set", "show", "describe"};
+    private static final String[] SQL = {"select", "insert", "import", "create", "use", "alter", "drop", "set", "show", "describe", "reset"};
     private static final String[] updateSQL = {"insert", "import", "create", "use", "alter", "drop", "set"};
     private static final String[] querySQL = {"select", "show", "describe"};
 
@@ -61,29 +61,11 @@ public class SqlSyntaxValidator {
 
     public static boolean isUseSql(String sql) {
         return sql.trim().toLowerCase().startsWith("use");
-//                || sql.trim().toLowerCase().matches("create\\s*database.*") || sql.toLowerCase().toLowerCase().matches("drop\\s*database.*");
-    }
-
-    public static boolean isShowSql(String sql) {
-        return sql.trim().toLowerCase().startsWith("show");
-    }
-
-    public static boolean isDescribeSql(String sql) {
-        return sql.trim().toLowerCase().startsWith("describe");
-    }
-
-
-    public static boolean isInsertSql(String sql) {
-        return sql.trim().toLowerCase().startsWith("insert") || sql.trim().toLowerCase().startsWith("import");
     }
 
     public static boolean isSelectSql(String sql) {
         return sql.trim().toLowerCase().startsWith("select");
     }
 
-    public static boolean isShowDatabaseSql(String sql) {
-        return sql.trim().toLowerCase().matches("show\\s*databases");
-    }
-
 
 }

src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/TaosInfo.java

@@ -7,9 +7,9 @@ import java.util.concurrent.atomic.AtomicLong;
 public class TaosInfo implements TaosInfoMBean {
 
     private static volatile TaosInfo instance;
-    private AtomicLong connect_open = new AtomicLong();
-    private AtomicLong connect_close = new AtomicLong();
-    private AtomicLong statement_count = new AtomicLong();
+    private final AtomicLong connect_open = new AtomicLong();
+    private final AtomicLong connect_close = new AtomicLong();
+    private final AtomicLong statement_count = new AtomicLong();
 
     static {
         try {

src/connector/jdbc/src/main/java/com/taosdata/jdbc/utils/Utils.java

@@ -22,8 +22,7 @@ import java.util.stream.IntStream;
 
 public class Utils {
 
-    private static Pattern ptn = Pattern.compile(".*?'");
-
+    private static final Pattern ptn = Pattern.compile(".*?'");
     private static final DateTimeFormatter milliSecFormatter = new DateTimeFormatterBuilder().appendPattern("yyyy-MM-dd HH:mm:ss.SSS").toFormatter();
     private static final DateTimeFormatter microSecFormatter = new DateTimeFormatterBuilder().appendPattern("yyyy-MM-dd HH:mm:ss.SSSSSS").toFormatter();
     private static final DateTimeFormatter nanoSecFormatter = new DateTimeFormatterBuilder().appendPattern("yyyy-MM-dd HH:mm:ss.SSSSSSSSS").toFormatter();
@@ -74,7 +73,7 @@ public class Utils {
 
     public static String escapeSingleQuota(String origin) {
         Matcher m = ptn.matcher(origin);
-        StringBuffer sb = new StringBuffer();
+        StringBuilder sb = new StringBuilder();
         int end = 0;
         while (m.find()) {
             end = m.end();
@@ -87,7 +86,7 @@ public class Utils {
                     sb.append(seg);
                 }
             } else { // len > 1
-                sb.append(seg.substring(0, seg.length() - 2));
+                sb.append(seg, 0, seg.length() - 2);
                 char lastcSec = seg.charAt(seg.length() - 2);
                 if (lastcSec == '\\') {
                     sb.append("\\'");
@@ -195,7 +194,7 @@ public class Utils {
 
     public static String formatTimestamp(Timestamp timestamp) {
         int nanos = timestamp.getNanos();
-        if (nanos % 1000000l != 0)
+        if (nanos % 1000000L != 0)
             return timestamp.toLocalDateTime().format(microSecFormatter);
         return timestamp.toLocalDateTime().format(milliSecFormatter);
     }

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBConnectionTest.java

@@ -5,7 +5,6 @@ import org.junit.Assert;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
-import javax.management.OperationsException;
 import java.sql.*;
 import java.util.Properties;
 

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBJNIConnectorTest.java

 package com.taosdata.jdbc;
 
 import org.junit.Test;
-import static org.junit.Assert.*;
 
+import java.lang.management.ManagementFactory;
+import java.lang.management.RuntimeMXBean;
 import java.sql.SQLException;
 import java.sql.SQLWarning;
 import java.util.ArrayList;
 import java.util.List;
 
-import java.lang.management.ManagementFactory;
-import java.lang.management.RuntimeMXBean;
-import java.lang.management.ThreadMXBean;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
 
 public class TSDBJNIConnectorTest {
 

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBParameterMetaDataTest.java

 package com.taosdata.jdbc;
 
-import com.taosdata.jdbc.rs.RestfulParameterMetaData;
 import org.junit.AfterClass;
 import org.junit.Assert;
 import org.junit.BeforeClass;

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBPreparedStatementTest.java

@@ -2,7 +2,6 @@ package com.taosdata.jdbc;
 
 import org.junit.*;
 
-import java.io.IOException;
 import java.math.BigDecimal;
 import java.sql.*;
 import java.util.ArrayList;
@@ -26,7 +25,7 @@ public class TSDBPreparedStatementTest {
         long ts = System.currentTimeMillis();
         pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setInt(2, 2);
-        pstmt_insert.setLong(3, 3l);
+        pstmt_insert.setLong(3, 3L);
         pstmt_insert.setFloat(4, 3.14f);
         pstmt_insert.setDouble(5, 3.1415);
         pstmt_insert.setShort(6, (short) 6);
@@ -53,8 +52,8 @@ public class TSDBPreparedStatementTest {
             Assert.assertEquals(ts, rs.getTimestamp(1).getTime());
             Assert.assertEquals(2, rs.getInt(2));
             Assert.assertEquals(2, rs.getInt("f1"));
-            Assert.assertEquals(3l, rs.getLong(3));
-            Assert.assertEquals(3l, rs.getLong("f2"));
+            Assert.assertEquals(3L, rs.getLong(3));
+            Assert.assertEquals(3L, rs.getLong("f2"));
             Assert.assertEquals(3.14f, rs.getFloat(4), 0.0);
             Assert.assertEquals(3.14f, rs.getFloat("f3"), 0.0);
             Assert.assertEquals(3.1415, rs.getDouble(5), 0.0);
@@ -312,14 +311,14 @@ public class TSDBPreparedStatementTest {
             Random r = new Random();
             s.setTableName("weather_test");
 
-            ArrayList<Long> ts = new ArrayList<Long>();
+            ArrayList<Long> ts = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 ts.add(System.currentTimeMillis() + i);
             }
             s.setTimestamp(0, ts);
 
             int random = 10 + r.nextInt(5);
-            ArrayList<String> s2 = new ArrayList<String>();
+            ArrayList<String> s2 = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 if (i % random == 0) {
                     s2.add(null);
@@ -330,7 +329,7 @@ public class TSDBPreparedStatementTest {
             s.setNString(1, s2, 4);
 
             random = 10 + r.nextInt(5);
-            ArrayList<Float> s3 = new ArrayList<Float>();
+            ArrayList<Float> s3 = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 if (i % random == 0) {
                     s3.add(null);
@@ -341,7 +340,7 @@ public class TSDBPreparedStatementTest {
             s.setFloat(2, s3);
 
             random = 10 + r.nextInt(5);
-            ArrayList<Double> s4 = new ArrayList<Double>();
+            ArrayList<Double> s4 = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 if (i % random == 0) {
                     s4.add(null);
@@ -352,7 +351,7 @@ public class TSDBPreparedStatementTest {
             s.setDouble(3, s4);
 
             random = 10 + r.nextInt(5);
-            ArrayList<Long> ts2 = new ArrayList<Long>();
+            ArrayList<Long> ts2 = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 if (i % random == 0) {
                     ts2.add(null);
@@ -379,13 +378,13 @@ public class TSDBPreparedStatementTest {
                 if (i % random == 0) {
                     sb.add(null);
                 } else {
-                    sb.add(i % 2 == 0 ? true : false);
+                    sb.add(i % 2 == 0);
                 }
             }
             s.setBoolean(6, sb);
 
             random = 10 + r.nextInt(5);
-            ArrayList<String> s5 = new ArrayList<String>();
+            ArrayList<String> s5 = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 if (i % random == 0) {
                     s5.add(null);
@@ -424,14 +423,14 @@ public class TSDBPreparedStatementTest {
             Random r = new Random();
             s.setTableName("weather_test");
 
-            ArrayList<Long> ts = new ArrayList<Long>();
+            ArrayList<Long> ts = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 ts.add(System.currentTimeMillis() + i);
             }
             s.setTimestamp(0, ts);
 
             int random = 10 + r.nextInt(5);
-            ArrayList<String> s2 = new ArrayList<String>();
+            ArrayList<String> s2 = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 if (i % random == 0) {
                     s2.add(null);
@@ -442,7 +441,7 @@ public class TSDBPreparedStatementTest {
             s.setNString(1, s2, 4);
 
             random = 10 + r.nextInt(5);
-            ArrayList<String> s3 = new ArrayList<String>();
+            ArrayList<String> s3 = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 if (i % random == 0) {
                     s3.add(null);
@@ -471,7 +470,7 @@ public class TSDBPreparedStatementTest {
     public void bindDataWithSingleTagTest() throws SQLException {
         Statement stmt = conn.createStatement();
 
-        String types[] = new String[]{"tinyint", "smallint", "int", "bigint", "bool", "float", "double", "binary(10)", "nchar(10)"};
+        String[] types = new String[]{"tinyint", "smallint", "int", "bigint", "bool", "float", "double", "binary(10)", "nchar(10)"};
 
         for (String type : types) {
             stmt.execute("drop table if exists weather_test");
@@ -510,21 +509,21 @@ public class TSDBPreparedStatementTest {
             }
 
 
-            ArrayList<Long> ts = new ArrayList<Long>();
+            ArrayList<Long> ts = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 ts.add(System.currentTimeMillis() + i);
             }
             s.setTimestamp(0, ts);
 
             int random = 10 + r.nextInt(5);
-            ArrayList<String> s2 = new ArrayList<String>();
+            ArrayList<String> s2 = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 s2.add("分支" + i % 4);
             }
             s.setNString(1, s2, 10);
 
             random = 10 + r.nextInt(5);
-            ArrayList<String> s3 = new ArrayList<String>();
+            ArrayList<String> s3 = new ArrayList<>();
             for (int i = 0; i < numOfRows; i++) {
                 s3.add("test" + i % 4);
             }
@@ -561,13 +560,13 @@ public class TSDBPreparedStatementTest {
         s.setTagString(1, "test");
 
 
-        ArrayList<Long> ts = new ArrayList<Long>();
+        ArrayList<Long> ts = new ArrayList<>();
         for (int i = 0; i < numOfRows; i++) {
             ts.add(System.currentTimeMillis() + i);
         }
         s.setTimestamp(0, ts);
 
-        ArrayList<String> s2 = new ArrayList<String>();
+        ArrayList<String> s2 = new ArrayList<>();
         for (int i = 0; i < numOfRows; i++) {
             s2.add("test" + i % 4);
         }
@@ -788,7 +787,7 @@ public class TSDBPreparedStatementTest {
     public void setBigDecimal() throws SQLException {
         // given
         long ts = System.currentTimeMillis();
-        BigDecimal bigDecimal = new BigDecimal(3.14444);
+        BigDecimal bigDecimal = new BigDecimal("3.14444");
 
         // when
         pstmt_insert.setTimestamp(1, new Timestamp(ts));
@@ -999,7 +998,7 @@ public class TSDBPreparedStatementTest {
         long ts = System.currentTimeMillis();
         pstmt_insert.setTimestamp(1, new Timestamp(ts));
         pstmt_insert.setInt(2, 2);
-        pstmt_insert.setLong(3, 3l);
+        pstmt_insert.setLong(3, 3L);
         pstmt_insert.setFloat(4, 3.14f);
         pstmt_insert.setDouble(5, 3.1415);
         pstmt_insert.setShort(6, (short) 6);

src/connector/jdbc/src/test/java/com/taosdata/jdbc/TSDBResultSetTest.java

@@ -95,13 +95,13 @@ public class TSDBResultSetTest {
     @Test
     public void getBigDecimal() throws SQLException {
         BigDecimal f1 = rs.getBigDecimal("f1");
-        Assert.assertEquals(1609430400000l, f1.longValue());
+        Assert.assertEquals(1609430400000L, f1.longValue());
 
         BigDecimal f2 = rs.getBigDecimal("f2");
         Assert.assertEquals(1, f2.intValue());
 
         BigDecimal f3 = rs.getBigDecimal("f3");
-        Assert.assertEquals(100l, f3.longValue());
+        Assert.assertEquals(100L, f3.longValue());
 
         BigDecimal f4 = rs.getBigDecimal("f4");
         Assert.assertEquals(3.1415f, f4.floatValue(), 0.00000f);
@@ -125,13 +125,13 @@ public class TSDBResultSetTest {
         Assert.assertEquals(1, Ints.fromByteArray(f2));
 
         byte[] f3 = rs.getBytes("f3");
-        Assert.assertEquals(100l, Longs.fromByteArray(f3));
+        Assert.assertEquals(100L, Longs.fromByteArray(f3));
 
         byte[] f4 = rs.getBytes("f4");
-        Assert.assertEquals(3.1415f, Float.valueOf(new String(f4)), 0.000000f);
+        Assert.assertEquals(3.1415f, Float.parseFloat(new String(f4)), 0.000000f);
 
         byte[] f5 = rs.getBytes("f5");
-        Assert.assertEquals(3.1415926, Double.valueOf(new String(f5)), 0.000000f);
+        Assert.assertEquals(3.1415926, Double.parseDouble(new String(f5)), 0.000000f);
 
         byte[] f6 = rs.getBytes("f6");
         Assert.assertTrue(Arrays.equals("abc".getBytes(), f6));
@@ -223,7 +223,7 @@ public class TSDBResultSetTest {
 
         Object f3 = rs.getObject("f3");
         Assert.assertEquals(Long.class, f3.getClass());
-        Assert.assertEquals(100l, f3);
+        Assert.assertEquals(100L, f3);
 
         Object f4 = rs.getObject("f4");
         Assert.assertEquals(Float.class, f4.getClass());
@@ -421,7 +421,7 @@ public class TSDBResultSetTest {
 
     @Test(expected = SQLFeatureNotSupportedException.class)
     public void updateLong() throws SQLException {
-        rs.updateLong(1, 1l);
+        rs.updateLong(1, 1L);
     }
 
     @Test(expected = SQLFeatureNotSupportedException.class)

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/BadLocaleSettingTest.java

@@ -3,12 +3,13 @@ package com.taosdata.jdbc.cases;
 
 import com.taosdata.jdbc.TSDBDriver;
 import org.junit.AfterClass;
-import org.junit.Assert;
 import org.junit.BeforeClass;
 import org.junit.Test;
-import java.io.IOException;
 
-import java.sql.*;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.sql.Statement;
 import java.util.Properties;
 
 public class BadLocaleSettingTest {

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/ConnectMultiTaosdByRestfulWithDifferentTokenTest.java

 package com.taosdata.jdbc.cases;
 
 import com.taosdata.jdbc.TSDBDriver;
+import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -9,13 +10,13 @@ import java.util.Properties;
 
 public class ConnectMultiTaosdByRestfulWithDifferentTokenTest {
 
-    private static String host1 = "192.168.17.156";
-    private static String user1 = "root";
-    private static String password1 = "tqueue";
+    private static final String host1 = "192.168.17.156";
+    private static final String user1 = "root";
+    private static final String password1 = "tqueue";
     private Connection conn1;
-    private static String host2 = "192.168.17.82";
-    private static String user2 = "root";
-    private static String password2 = "taosdata";
+    private static final String host2 = "192.168.17.82";
+    private static final String user2 = "root";
+    private static final String password2 = "taosdata";
     private Connection conn2;
 
     @Test
@@ -30,6 +31,7 @@ public class ConnectMultiTaosdByRestfulWithDifferentTokenTest {
         try (Statement stmt = connection.createStatement()) {
             ResultSet rs = stmt.executeQuery("select server_status()");
             ResultSetMetaData meta = rs.getMetaData();
+            Assert.assertNotNull(meta);
             while (rs.next()) {
             }
         } catch (SQLException e) {

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/DriverAutoloadTest.java

@@ -13,7 +13,7 @@ import java.util.Properties;
 public class DriverAutoloadTest {
 
     private Properties properties;
-    private String host = "127.0.0.1";
+    private final String host = "127.0.0.1";
 
     @Test
     public void testRestful() throws SQLException {

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/InsertDbwithoutUseDbTest.java

@@ -13,9 +13,9 @@ import java.util.Random;
 @FixMethodOrder(MethodSorters.NAME_ASCENDING)
 public class InsertDbwithoutUseDbTest {
 
-    private static String host = "127.0.0.1";
+    private static final String host = "127.0.0.1";
     private static Properties properties;
-    private static Random random = new Random(System.currentTimeMillis());
+    private static final Random random = new Random(System.currentTimeMillis());
 
     @Test
     public void case001() throws ClassNotFoundException, SQLException {

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/InsertSpecialCharacterJniTest.java

@@ -8,14 +8,14 @@ public class InsertSpecialCharacterJniTest {
 
     private static final String host = "127.0.0.1";
     private static Connection conn;
-    private static String dbName = "spec_char_test";
-    private static String tbname1 = "test";
-    private static String tbname2 = "weather";
-    private static String special_character_str_1 = "$asd$$fsfsf$";
-    private static String special_character_str_2 = "\\\\asdfsfsf\\\\";
-    private static String special_character_str_3 = "\\\\asdfsfsf\\";
-    private static String special_character_str_4 = "?asd??fsf?sf?";
-    private static String special_character_str_5 = "?#sd@$f(('<(s[P)>\"){]}f?s[]{}%vaew|\"fsfs^a&d*jhg)(j))(f@~!?$";
+    private static final String dbName = "spec_char_test";
+    private static final String tbname1 = "test";
+    private static final String tbname2 = "weather";
+    private static final String special_character_str_1 = "$asd$$fsfsf$";
+    private static final String special_character_str_2 = "\\\\asdfsfsf\\\\";
+    private static final String special_character_str_3 = "\\\\asdfsfsf\\";
+    private static final String special_character_str_4 = "?asd??fsf?sf?";
+    private static final String special_character_str_5 = "?#sd@$f(('<(s[P)>\"){]}f?s[]{}%vaew|\"fsfs^a&d*jhg)(j))(f@~!?$";
 
     @Test
     public void testCase01() throws SQLException {

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/InsertSpecialCharacterRestfulTest.java

@@ -8,14 +8,14 @@ public class InsertSpecialCharacterRestfulTest {
 
     private static final String host = "127.0.0.1";
     private static Connection conn;
-    private static String dbName = "spec_char_test";
-    private static String tbname1 = "test";
-    private static String tbname2 = "weather";
-    private static String special_character_str_1 = "$asd$$fsfsf$";
-    private static String special_character_str_2 = "\\\\asdfsfsf\\\\";
-    private static String special_character_str_3 = "\\\\asdfsfsf\\";
-    private static String special_character_str_4 = "?asd??fsf?sf?";
-    private static String special_character_str_5 = "?#sd@$f(('<(s[P)>\"){]}f?s[]{}%vaew|\"fsfs^a&d*jhg)(j))(f@~!?$";
+    private static final String dbName = "spec_char_test";
+    private static final String tbname1 = "test";
+    private static final String tbname2 = "weather";
+    private static final String special_character_str_1 = "$asd$$fsfsf$";
+    private static final String special_character_str_2 = "\\\\asdfsfsf\\\\";
+    private static final String special_character_str_3 = "\\\\asdfsfsf\\";
+    private static final String special_character_str_4 = "?asd??fsf?sf?";
+    private static final String special_character_str_5 = "?#sd@$f(('<(s[P)>\"){]}f?s[]{}%vaew|\"fsfs^a&d*jhg)(j))(f@~!?$";
 
     @Test
     public void testCase01() throws SQLException {

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/InvalidResultSetPointerTest.java

@@ -8,13 +8,13 @@ import java.util.Properties;
 
 public class InvalidResultSetPointerTest {
 
-    private static String host = "127.0.0.1";
+    private static final String host = "127.0.0.1";
     private static final String dbName = "test";
     private static final String stbName = "stb";
     private static final String tbName = "tb";
     private static Connection connection;
-    private static int numOfSTb = 30000;
-    private static int numOfTb = 3;
+    private static final int numOfSTb = 30000;
+    private static final int numOfTb = 3;
     private static int numOfThreads = 100;
 
     @Test
@@ -74,7 +74,7 @@ public class InvalidResultSetPointerTest {
             b = numOfSTb % numOfThreads;
         }
 
-        multiThreadingClass instance[] = new multiThreadingClass[numOfThreads];
+        multiThreadingClass[] instance = new multiThreadingClass[numOfThreads];
 
         int last = 0;
         for (int i = 0; i < numOfThreads; i++) {

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/MultiThreadsWithSameStatementTest.java

@@ -9,8 +9,7 @@ import java.util.concurrent.TimeUnit;
 
 public class MultiThreadsWithSameStatementTest {
 
-
-    private class Service {
+    private static class Service {
         public Connection conn;
         public Statement stmt;
 

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/StableTest.java

@@ -16,9 +16,9 @@ import static org.junit.Assert.assertEquals;
 public class StableTest {
 
     private static Connection connection;
-    private static String dbName = "test";
-    private static String stbName = "st";
-    private static String host = "127.0.0.1";
+    private static final String dbName = "test";
+    private static final String stbName = "st";
+    private static final String host = "127.0.0.1";
 
     @BeforeClass
     public static void createDatabase() {

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/TaosInfoMonitorTest.java

@@ -25,7 +25,7 @@ public class TaosInfoMonitorTest {
             return null;
         }).collect(Collectors.toList());
 
-        connectionList.stream().forEach(conn -> {
+        connectionList.forEach(conn -> {
             try (Statement stmt = conn.createStatement()) {
                 ResultSet rs = stmt.executeQuery("show databases");
                 while (rs.next()) {
@@ -37,7 +37,7 @@ public class TaosInfoMonitorTest {
             }
         });
 
-        connectionList.stream().forEach(conn -> {
+        connectionList.forEach(conn -> {
             try {
                 conn.close();
                 TimeUnit.MILLISECONDS.sleep(100);

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/TimestampPrecisionInNanoInJniTest.java

@@ -22,7 +22,7 @@ public class TimestampPrecisionInNanoInJniTest {
     private static final long timestamp3 = (timestamp1 + 10) * 1000_000 + 123456;
     private static final Format format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
     private static final String date1 = format.format(new Date(timestamp1));
-    private static final String date4 = format.format(new Date(timestamp1 + 10l));
+    private static final String date4 = format.format(new Date(timestamp1 + 10L));
     private static final String date2 = date1 + "123455";
     private static final String date3 = date4 + "123456";
     

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/UnsignedNumberJniTest.java

@@ -44,7 +44,7 @@ public class UnsignedNumberJniTest {
                 Assert.assertEquals(127, rs.getByte(2));
                 Assert.assertEquals(32767, rs.getShort(3));
                 Assert.assertEquals(2147483647, rs.getInt(4));
-                Assert.assertEquals(9223372036854775807l, rs.getLong(5));
+                Assert.assertEquals(9223372036854775807L, rs.getLong(5));
             }
         } catch (SQLException e) {
             e.printStackTrace();

src/connector/jdbc/src/test/java/com/taosdata/jdbc/cases/UnsignedNumberRestfulTest.java

@@ -45,7 +45,7 @@ public class UnsignedNumberRestfulTest {
                 Assert.assertEquals(127, rs.getByte(2));
                 Assert.assertEquals(32767, rs.getShort(3));
                 Assert.assertEquals(2147483647, rs.getInt(4));
-                Assert.assertEquals(9223372036854775807l, rs.getLong(5));
+                Assert.assertEquals(9223372036854775807L, rs.getLong(5));
             }
         } catch (SQLException e) {
             e.printStackTrace();

src/connector/jdbc/src/test/java/com/taosdata/jdbc/rs/RestfulResultSetTest.java

@@ -95,13 +95,13 @@ public class RestfulResultSetTest {
     public void getBigDecimal() throws SQLException {
         BigDecimal f1 = rs.getBigDecimal("f1");
         long actual = (f1 == null) ? 0 : f1.longValue();
-        Assert.assertEquals(1609430400000l, actual);
+        Assert.assertEquals(1609430400000L, actual);
 
         BigDecimal f2 = rs.getBigDecimal("f2");
         Assert.assertEquals(1, f2.intValue());
 
         BigDecimal f3 = rs.getBigDecimal("f3");
-        Assert.assertEquals(100l, f3.longValue());
+        Assert.assertEquals(100L, f3.longValue());
 
         BigDecimal f4 = rs.getBigDecimal("f4");
         Assert.assertEquals(3.1415f, f4.floatValue(), 0.00000f);
@@ -125,13 +125,13 @@ public class RestfulResultSetTest {
         Assert.assertEquals(1, Ints.fromByteArray(f2));
 
         byte[] f3 = rs.getBytes("f3");
-        Assert.assertEquals(100l, Longs.fromByteArray(f3));
+        Assert.assertEquals(100L, Longs.fromByteArray(f3));
 
         byte[] f4 = rs.getBytes("f4");
-        Assert.assertEquals(3.1415f, Float.valueOf(new String(f4)), 0.000000f);
+        Assert.assertEquals(3.1415f, Float.parseFloat(new String(f4)), 0.000000f);
 
         byte[] f5 = rs.getBytes("f5");
-        Assert.assertEquals(3.1415926, Double.valueOf(new String(f5)), 0.000000f);
+        Assert.assertEquals(3.1415926, Double.parseDouble(new String(f5)), 0.000000f);
 
         byte[] f6 = rs.getBytes("f6");
         Assert.assertEquals("abc", new String(f6));
@@ -222,7 +222,7 @@ public class RestfulResultSetTest {
 
         Object f3 = rs.getObject("f3");
         Assert.assertEquals(Long.class, f3.getClass());
-        Assert.assertEquals(100l, f3);
+        Assert.assertEquals(100L, f3);
 
         Object f4 = rs.getObject("f4");
         Assert.assertEquals(Float.class, f4.getClass());
@@ -434,7 +434,7 @@ public class RestfulResultSetTest {
 
     @Test(expected = SQLFeatureNotSupportedException.class)
     public void updateLong() throws SQLException {
-        rs.updateLong(1, 1l);
+        rs.updateLong(1, 1L);
     }
 
     @Test(expected = SQLFeatureNotSupportedException.class)

src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/OSUtilsTest.java

@@ -10,17 +10,17 @@ public class OSUtilsTest {
 
     @Test
     public void inWindows() {
-        Assert.assertEquals(OS.indexOf("win") >= 0, OSUtils.isWindows());
+        Assert.assertEquals(OS.contains("win"), OSUtils.isWindows());
     }
 
     @Test
     public void isMac() {
-        Assert.assertEquals(OS.indexOf("mac") >= 0, OSUtils.isMac());
+        Assert.assertEquals(OS.contains("mac"), OSUtils.isMac());
     }
 
     @Test
     public void isLinux() {
-        Assert.assertEquals(OS.indexOf("nux") >= 0, OSUtils.isLinux());
+        Assert.assertEquals(OS.contains("nux"), OSUtils.isLinux());
     }
 
     @Before

src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/TimestampUtil.java

@@ -21,47 +21,4 @@ public class TimestampUtil {
         SimpleDateFormat sdf = new SimpleDateFormat(datetimeFormat);
         return sdf.format(new Date(time));
     }
-
-    public static class TimeTuple {
-        public Long start;
-        public Long end;
-        public Long timeGap;
-
-        TimeTuple(long start, long end, long timeGap) {
-            this.start = start;
-            this.end = end;
-            this.timeGap = timeGap;
-        }
-    }
-
-    public static TimeTuple range(long start, long timeGap, long size) {
-        long now = System.currentTimeMillis();
-        if (timeGap < 1)
-            timeGap = 1;
-        if (start == 0)
-            start = now - size * timeGap;
-
-        // 如果size小于1异常
-        if (size < 1)
-            throw new IllegalArgumentException("size less than 1.");
-        // 如果timeGap为1，已经超长，需要前移start
-        if (start + size > now) {
-            start = now - size;
-            return new TimeTuple(start, now, 1);
-        }
-        long end = start + (long) (timeGap * size);
-        if (end > now) {
-            //压缩timeGap
-            end = now;
-            double gap = (end - start) / (size * 1.0f);
-            if (gap < 1.0f) {
-                timeGap = 1;
-                start = end - size;
-            } else {
-                timeGap = (long) gap;
-                end = start + (long) (timeGap * size);
-            }
-        }
-        return new TimeTuple(start, end, timeGap);
-    }
 }

src/connector/jdbc/src/test/java/com/taosdata/jdbc/utils/UtilsTest.java

@@ -3,8 +3,6 @@ package com.taosdata.jdbc.utils;
 import org.junit.Assert;
 import org.junit.Test;
 
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
 import java.util.stream.Stream;
 
 public class UtilsTest {
@@ -19,14 +17,14 @@ public class UtilsTest {
         Assert.assertEquals("\\'\\'\\'\\'\\'a\\'", news);
 
         // given
-        s = "\'''''a\\'";
+        s = "'''''a\\'";
         // when
         news = Utils.escapeSingleQuota(s);
         // then
         Assert.assertEquals("\\'\\'\\'\\'\\'a\\'", news);
 
         // given
-        s = "\'\'\'\''a\\'";
+        s = "'''''a\\'";
         // when
         news = Utils.escapeSingleQuota(s);
         // then