Accessing database with JDBC through Java

JDBC Example to access Database

import java.sql.*;

public class JdbcConnect{
  public static void main(String[] args) {
  System.out.println("JDBC Example.");
  Connection connnection = null;
  String url = "jdbc:mysql://localhost:3306/";
  String dbName = "student";
  String driver = "com.mysql.jdbc.Driver";
  String userName = "root"; 
  String password = "root";
  try {
  Class.forName(driver).newInstance();
  connnection  = DriverManager.getConnection(url+dbName,userName,password);
  System.out.println("Connected to the database");
  connnection .close();
  System.out.println("Disconnected from database");
  } catch (Exception e) {
  e.printStackTrace();
  }
  }
}

Connection: This is an interface in java.sql package that specifies connection with specific database like: MySQL, Ms-Access, Oracle etc and java files. The SQL statements are executed within the context of the Connection interface.

Class.forName(String driver): This method is static. It attempts to load the class and returns class instance and takes string type value (driver) after that matches class with given string.

DriverManager: It is a class of java.sql package that controls a set of JDBC drivers. Each driver has to be register with this class.

getConnection(String url, String userName, String password): This method establishes a connection to specified database url. It takes three string types of arguments like:

url: - Database url where stored or created your database

userName: - User name of MySQL

password: -Password of MySQL

con.close(): This method is used for disconnecting the connection. It frees all the resources occupied by the database.

printStackTrace(): The method is used to show error messages. If the connection is not established then exception is thrown and print the message.