Overview of Interfaces and Classes used in this example

The java.lang.Class class

Objects of this class represent classes and interfaces in a running Java application. Class objects are constructed automatically by the Java Virtual Machine as classes are loaded.

Methods

• public static Class forName(String className) - This method is used for loading classes. It returns the Class object associated with the class or interface with the given string name.

The java.sql.DriverManager Class

This class maintains a list of registered Driver classes.

Methods

• public static Connection getConnection(String url) - This method can be used to establish a connection to the given database URL. The DriverManager selects an appropriate driver from the set of registered JDBC drivers.

The java.sql.Connection Interface

A Connection object represents a connection with the database. An application can have one or more connections with a database.

Methods

• public Statement createStatement() - It creates a Statement object for sending SQL statements to the database.

The java.sql.Statement Interface

The Statement object is used to send SQL statements to a database.

Methods

• public ResultSet executeQuery(String sql) - It executes an SQL statement that returns a single ResultSet object.
• public int executeUpdate(String sql) - It executes an SQL INSERT, UPDATE or DELETE statement.

The java.sql.ResultSet Interface

A ResultSet object contains the results of executing an SQL query.

Methods

• public boolean next() - It moves the cursor to the next row. A ResultSet cursor is initially positioned before the first row; the first call to the next() method makes the first row the current row.