In this tutorial you will learn about java.sql.Connection interface, and how to use this interface to get a connection to the database
In this tutorial you will learn about java.sql.Connection interface, and how to use this interface to get a connection to the databaseJDBC Connection is an interface of java.sql.*; package. An connection object represents a connection with specific database. A single application can have more than one Connection object with a single database or more databases. It create a session with a database, this session have the Sql statement to execute and results are returned.
You can get a information about a connection Connection.getMetaData() method. This method returns a MetaData object, that contains the information about database and tables.
To create a connection with database you need to call a method DriverManager.getConnection("ConnectionURL");. This returns a reference of a connection to the connection object.
Class.forName("com.mysql.jdbc.Driver");
The above code registers the river for MySql database.
Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306/student","userName","userPassword");
Now lets see an example to establish the connection to the MuSql database.
At first create a database named 'student' in MySql and then create a table named 'student'.
CREATE TABLE student (
RollNo int(9) PRIMARY KEY NOT NULL,
Name tinytext NOT NULL,
Course varchar(25) NOT NULL,
Address text
);
JDBCCOnnectionExample .java
package roseindia.net;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
public class JDBCCOnnectionExample {
Connection connection = null;
public JDBCCOnnectionExample() {
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e) {
System.out.println(e.toString());
}
}
public Connection createConnection() {
Connection con = null;
if (connection != null) {
System.out.println("Cant create a connection");
} else {
try {
con = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/student", "root",
"root");
System.out.println("Connection created Successfully");
DatabaseMetaData dbMetaData = con.getMetaData();
ResultSet dbInfo = dbMetaData.getCatalogs();
System.out.println("Getting Concurrency of MetaData");
System.out.println(dbInfo.getConcurrency());
} catch (SQLException e) {
System.out.println(e.toString());
}
}
return con;
}
public static void main(String[] args) throws SQLException {
JDBCCOnnectionExample jdbccOnnectionExample = new JDBCCOnnectionExample();
Connection conn = jdbccOnnectionExample.createConnection();
conn.close();
}
}
| Connection created Successfully Getting Concurrency of MetaData 1007 |