Merge pull request #4356 from taosdata/hotfix/TD-2132

Hotfix/td 2132

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

+package com.taosdata.jdbc.cases;
+
+import org.junit.Test;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+public class AppMemoryLeakTest {
+
+    @Test(expected = SQLException.class)
+    public void testCreateTooManyConnection() throws ClassNotFoundException, SQLException {
+        Class.forName("com.taosdata.jdbc.TSDBDriver");
+        int conCnt = 0;
+        while (true) {
+            Connection conn = DriverManager.getConnection("jdbc:TAOS://localhost:6030/?user=root&password=taosdata");
+            System.out.println(conCnt++ + " : " + conn);
+        }
+    }
+
+    @Test
+    public void testCreateTooManyStatement() throws ClassNotFoundException, SQLException {
+        Class.forName("com.taosdata.jdbc.TSDBDriver");
+        int stmtCnt = 0;
+        Connection conn = DriverManager.getConnection("jdbc:TAOS://localhost:6030/?user=root&password=taosdata");
+        while (true) {
+            Statement stmt = conn.createStatement();
+            System.out.println(++stmtCnt + " : " + stmt);
+        }
+    }
+
+    public static void main(String[] args) throws ClassNotFoundException, SQLException {
+        Class.forName("com.taosdata.jdbc.TSDBDriver");
+        int stmtCnt = 0;
+        Connection conn = DriverManager.getConnection("jdbc:TAOS://localhost:6030/?user=root&password=taosdata");
+        while (true) {
+            Statement stmt = conn.createStatement();
+            System.out.println(++stmtCnt + " : " + stmt);
+        }
+    }
+
+
+}