import java.sql.*;

public class SqlServerTest {

         public static void main(String []args) {

         String driverName="com.mysql.jdbc.Driver";

         String dbURL="jdbc:mysql://$ip:3306/$db";

         String userName="$user";

         String userPwd="$password";

          try

        {

            Class.forName(driverName);

            Connection dbConn=DriverManager.getConnection(dbURL,userName,userPwd);

            Statement st = dbConn.createStatement();

            ResultSet rs = st.executeQuery("select * from user");

            while (rs.next()) {

              System.out.println(rs.getString(1));

            }

            System.out.println("success!");

         }

          catch(Exception e)

       {

            e.printStackTrace();

            System.out.print("fail!");

       }

    }

 }

import java.sql.*;

public class SqlServerTest {

         public static void main(String []args) {

         String driverName="com.microsoft.sqlserver.jdbc.SQLServerDriver";

         String dbURL="jdbc:sqlserver://$ip:1433;DatabaseName=$db";

         String userName="$user";

         String userPwd="$password";

          try

        {

            Class.forName(driverName);

            Connection dbConn=DriverManager.getConnection(dbURL,userName,userPwd);

            Statement st = dbConn.createStatement();

            ResultSet rs = st.executeQuery("select * from sysobjects where xtype='U'");

            while (rs.next()) {

              System.out.println(rs.getString(1));

            }

            System.out.println("success!");

         }

          catch(Exception e)

       {

            e.printStackTrace();

            System.out.print("fail!");

       }

    }

 }

import java.sql.*;

public class SqlServerTest {

         public static void main(String []args) {

         String driverName="oracle.jdbc.driver.OracleDriver";

         String dbURL="jdbc:oracle:thin:@//$ip:1521/$db";

         String userName="$user";

         String userPwd="$password";

          try

        {

            Class.forName(driverName);

            Connection dbConn=DriverManager.getConnection(dbURL,userName,userPwd);

            Statement st = dbConn.createStatement();

            ResultSet rs = st.executeQuery("select * from all_tab_comments");

            while (rs.next()) {

              System.out.println(rs.getString(1));

            }

            System.out.println("success!");

         }

          catch(Exception e)

       {

            e.printStackTrace();

            System.out.print("fail!");

       }

    }

 }