JDBC driver registered in 3 ways

MySQL to drive for example, describes three ways to register the driver's

1: Class.forName ( "com.mysql.cj.jdbc.Driver"); // load the database driver

. 1  Package com.pine.interview.jdbc;
 2  
. 3  Import the java.sql.Connection;
 . 4  Import the java.sql.DriverManager;
 . 5  Import java.sql.SQLException;
 . 6  
. 7  public  class Driver1 {
 . 8      public  static  void main (String [] args) throws a ClassNotFoundException, SQLException {
 . 9          the Class.forName ( "com.mysql.cj.jdbc.Driver"); // load database driver 
10          String URL = "JDBC: MySQL: // localhost: 3306 / Pine serverTimezone = UTC? "; // database connection sub-protocol 
11         Connection conn = DriverManager.getConnection(url, "root", "root");
12         System.out.println(conn);
13         conn.close();
14     }
15 }

2: System.setProperty ( "jdbc.drivers", "com.mysql.cj.jdbc.Driver"); // load database driver

. 1  Package com.pine.interview.jdbc;
 2  
. 3  Import the java.sql.Connection;
 . 4  Import the java.sql.DriverManager;
 . 5  Import java.sql.SQLException;
 . 6  
. 7  public  class Driver2 {
 . 8      public  static  void main (String [] args) throws a ClassNotFoundException, SQLException {
 . 9          System.setProperty ( "the jdbc.drivers", "com.mysql.cj.jdbc.Driver"); // load database driver 
10          String URL = "JDBC: MySQL: // localhost: 3306 ? / Pine serverTimezone UTC = "; // database connection sub-protocol 
11         Conn = the DriverManager.getConnection Connection (URL, "the root", "the root" );
 12 is          System.out.println (Conn);
 13 is          conn.Close ();
 14          / ** 
15              * may be introduced simultaneously driving a plurality of jdbc intermediate colon ":" separated
 16                such System.setProperty ( "the jdbc.drivers", "XXXDriver: XXXDriver: XXXDriver");
 . 17           * / 
18 is      }
 . 19 }

3: new com.mysql.cj.jdbc.Driver (); // load database driver

. 1  Package com.pine.interview.jdbc;
 2  
. 3  Import the java.sql.Connection;
 . 4  Import the java.sql.DriverManager;
 . 5  Import java.sql.SQLException;
 . 6  
. 7  public  class Driver3 {
 . 8      public  static  void main (String [] args) throws SQLException {
 . 9          new new com.mysql.cj.jdbc.Driver (); // load database driver 
10          String URL = "JDBC: MySQL: // localhost: 3306 / Pine serverTimezone = UTC?"; // database connection sub-protocol 
11         Connection conn = DriverManager.getConnection(url, "root", "root");
12         System.out.println(conn);
13         conn.close();
14     }
15 }

Recommended Method 1, Method 2, Method 2 wherein the plurality of driving time registration can

Method 3 is not recommended, because it will compile-time dependencies mysql driver package, and a static block will register for driving, examples of the new Driver out superfluous useless

As shown below: