JDBC Driver Connection URL

MySQL Tutorials - Herong's Tutorial Examples

∟JDBC Driver Connection URL

Describes the connection URL format and how to create connection objects with the DriverManager class.

If you want to use the DriverManager class to create connection objects, you need to know how to make a connection URL that provides access information to the MySQL server. The MySQL connection URL has the following format:

jdbc:mysql://[host][:port]/[database][?property1][=value1]...

  host - The host name where MySQL server is running.
         Default is 127.0.0.1 - the IP address of localhost.

  port - The port number where MySQL is listening for connection.
         Default is 3306.

  Database - The name of an existing database on MySQL server.
         If not specified, the connection starts no current database.

  Property - The name of a supported connection properties.
         "user" and "password" are 2 most important properties.

  Value - The value for the specified connection property.

Here are some example connection URLs:

jdbc:mysql://localhost:3306/test?user=root&password=TopSecret
jdbc:mysql://:3306/test?user=root&password=TopSecret
jdbc:mysql://localhost/test?user=root&password=TopSecret
jdbc:mysql://localhost:3306/?user=root&password=TopSecret
jdbc:mysql://localhost/?user=root&password=TopSecret
jdbc:mysql://:3306/?user=root&password=TopSecret
jdbc:mysql:///test?user=root&password=TopSecret
jdbc:mysql:///?user=root&password=TopSecret

I wrote the following program to validate some of the connection URLs listed above:

/* MySqlConnectionUrl2.java
 * Copyright (c) 2005 HerongYang.com. All Rights Reserved.
 */
import java.sql.*;
public class MySqlConnectionUrl2 {
  public static void main(String [] args) {
    Connection con = null;
    try {
      con = DriverManager.getConnection(
        "jdbc:mysql://localhost:3306/test?"
        + "user=root&password=TopSecret");
      System.out.println("Connected with host:port/database.");
      con.close();

      con = DriverManager.getConnection(
        "jdbc:mysql://:3306/test?"
        + "user=root&password=TopSecret");
      System.out.println("Connected with default host.");
      con.close();

      con = DriverManager.getConnection(
        "jdbc:mysql://localhost/test?"
        + "user=root&password=TopSecret");
      System.out.println("Connected with default port.");
      con.close();

      con = DriverManager.getConnection(
        "jdbc:mysql://localhost:3306/?"
        + "user=root&password=TopSecret");
      System.out.println("Connected with no database.");
      con.close();

      con = DriverManager.getConnection(
        "jdbc:mysql:///?"
        + "user=root&password=TopSecret");
      System.out.println("Connected with properties only.");
      con.close();

    } catch (Exception e) {
      System.err.println("Exception: "+e.getMessage());
    }
  }
}

Here is the output of running the above program on my MySQL Server 8 with default settings and JDK 12.

herong> javac MySqlConnectionUrl2.java

herong> java -cp .;\local\lib\mysql-connector-java-8.0.17.jar
   MySqlConnectionUrl2

Connected with host:port/database.
Connected with default host.
Connected with default port.
Connected with no database.
Connected with properties only.

Note that:

The DriverManager.getConnection() method will automatically load JDBC driver implementation class, com.mysql.cj.jdbc.Driver. There is no need to load it with Class.forName("com.mysql.cj.jdbc.Driver") call as shown in the previous example.
mysql-connector-java-8.0.17.jar does support the new authentication method, "caching_sha2_password", since the "root" user account was created with the default option of "caching_sha2_password".