What is JDBC? Explain different types of JDBC drivers. Write a JDBC program to display student details from student table.

 JDBC (Java Database Connectivity) is a Java API used to connect and interact with a database. It provides a standard set of interfaces for accessing different types of databases using Java programming language.

There are four types of JDBC drivers:

1. JDBC-ODBC Bridge Driver: This driver uses an ODBC (Open Database Connectivity) driver to connect to the database. It is suitable for small applications that require connectivity to a single database.
2. Native-API Driver: This driver uses the database’s native API to connect to the database. It is platform-dependent and is not suitable for all databases.
3. Network Protocol Driver: This driver communicates with the database server using a network protocol specific to the database. It is suitable for all databases that support a network protocol.
4. Thin Driver: This driver is fully written in Java and communicates with the database server using a network protocol. It is platform-independent and is suitable for all databases that support a network protocol.

Here is an example of a JDBC program that displays student details from a student table:

import java.sql.*;
public class StudentDetails {
   static final String DB_URL = "jdbc:mysql://localhost/STUDENT";
   static final String USER = "username";
   static final String PASS = "password";
   public static void main(String[] args) {
      Connection conn = null;
      Statement stmt = null;
      try {
         // Register JDBC driver
         Class.forName("com.mysql.jdbc.Driver");

         // Open a connection
         System.out.println("Connecting to database...");

         conn = DriverManager.getConnection(DB_URL,USER,PASS);

         // Execute a query
         System.out.println("Creating statement...");
         stmt = conn.createStatement();
         String sql;
         sql = "SELECT id, name, age FROM student";
         ResultSet rs = stmt.executeQuery(sql);

         // Extract data from result set
         while(rs.next()){
            //Retrieve by column name
            int id  = rs.getInt("id");

            String name = rs.getString("name");
            int age = rs.getInt("age");

            //Display values
            System.out.print("ID: " + id);
            System.out.print(", Name: " + name);
            System.out.println(", Age: " + age);
         }

         // Clean-up environment
         rs.close();
         stmt.close();
         conn.close();
      } catch(SQLException se) {

         // Handle errors for JDBC
         se.printStackTrace();
      } catch(Exception e) {
         // Handle errors for Class.forName
         e.printStackTrace();
      } finally {

         // finally block used to close resources
         try {
            if(stmt!=null)
               stmt.close();
         } catch(SQLException se2) {
         } // nothing we can do
         try {
            if(conn!=null)
            conn.close();
         } catch(SQLException se) {
            se.printStackTrace();
         } // end finally try
      } // end try
      System.out.println("Goodbye!");
   }
}

In this program, we first register the JDBC driver, then establish a connection to the database using the provided username and password. We then execute a SQL query to retrieve student details from the student table, and display the results in the console. Finally, we clean up the resources and close the connection.