What are the necessary steps to work with JDBC ?

There are 5 steps to work with JDBC as illustrated with an example below:

1. import java.sql.DriverManager;
2. import java.sql.Connection;
3. import java.sql.ResultSet;
4. import java.sql.Statement;
5. import java.math.BigDecimal;
6. import java.sql.Blob;
7. 
   
8. public class JDBCConfiguration {
9. 
   
10. public static void main(String[] args) {
11. 
    
12. Connection con = null;
13. Statement stmt = null;
14. ResultSet rs = null;
15. try {
16. 
    
17. // 1. Load the driver
18. Class.forName("com.mysql.jdbc.Driver");
19. 
    
20. // 2. Get the DB connection via driver
21. String dbURL = "jdbc:mysql://ishaan-pc:3306/mydb?user=root&password=root";
22. con = DriverManager.getConnection(dbURL); // DriverManager : class
23. // getConnection() : static
24. 
    
25. // 3. Execute the SQL query via connection
26. String query = "SELECT * FROM EMPLOYEE";
27. stmt = con.createStatement();
28. rs = stmt.executeQuery(query);
29. 
    
30. // 4. Process the result
31. while (rs.next()) {
32. int id = rs.getInt("empid");
33. String name = rs.getString("empname");
34. long age = rs.getLong("age");
35. double salary = rs.getDouble("salary");
36. BigDecimal serialNumber = rs.getBigDecimal("serialnum");
37. boolean status = rs.getBoolean("status");
38. /*
39. * BLOB - Binary Large Object that contains a variable amount of
40. * data. Values are treated as binary strings.We don't need to
41. * specify length while creating a column
42. */
43. Blob picture = rs.getBlob("emppicture");
44. 
    
45. System.out.println("emp id: " + id);
46. System.out.println("emp name: " + name);
47. System.out.println("emp age: " + age);
48. System.out.println("emp salary: " + salary);
49. System.out.println("emp serial no: " + serialNumber);
50. System.out.println("Is emp active?: " + status);
51. System.out.println("emp photo: " + picture);
52. 
    
53. }
54. } catch (Exception e) {
55. System.out.println("exception occured due to : " + e);
56. } finally {
57. 
    
58. // 5. Close all the JDBC objects
59. try {
60. if (con != null) {
61. con.close();
62. }
63. if (stmt != null) {
64. stmt.close();
65. }
66. if (rs != null) {
67. rs.close();
68. }
69. } catch (Exception e) {
70. System.out.println("exception occured in finally block : " + e);
71. }
72. }
73. }
74. }

Output: 

emp id: 101

emp name: ishaan

emp age: 21

emp salary: 9000

emp serial no: 11229933994439101

Is emp active?: true

emp photo: 👨