/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * particular file as subject to the "Classpath" exception as provided

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 */

package java.sql;

/**

 * The interface that every driver class must implement.

 * <P>The Java SQL framework allows for multiple database drivers.

 *

 * <P>Each driver should supply a class that implements

 * the Driver interface.

 *

 * <P>The DriverManager will try to load as many drivers as it can

 * find and then for any given connection request, it will ask each

 * driver in turn to try to connect to the target URL.

 *

 * <P>It is strongly recommended that each Driver class should be

 * small and standalone so that the Driver class can be loaded and

 * queried without bringing in vast quantities of supporting code.

 *

 * <P>When a Driver class is loaded, it should create an instance of

 * itself and register it with the DriverManager. This means that a

 * user can load and register a driver by calling

 * <pre>

 *   <code>Class.forName("foo.bah.Driver")</code>

 * </pre>

 *

 * @see DriverManager

 * @see Connection

 */

public interface Driver {

    /**

     * Attempts to make a database connection to the given URL.

     * The driver should return "null" if it realizes it is the wrong kind

     * of driver to connect to the given URL.  This will be common, as when

     * the JDBC driver manager is asked to connect to a given URL it passes

     * the URL to each loaded driver in turn.

     *

     * <P>The driver should throw an <code>SQLException</code> if it is the right

     * driver to connect to the given URL but has trouble connecting to

     * the database.

     *

     * <P>The <code>java.util.Properties</code> argument can be used to pass

     * arbitrary string tag/value pairs as connection arguments.

     * Normally at least "user" and "password" properties should be

     * included in the <code>Properties</code> object.

     *

     * @param url the URL of the database to which to connect

     * @param info a list of arbitrary string tag/value pairs as

     * connection arguments. Normally at least a "user" and

     * "password" property should be included.

     * @return a <code>Connection</code> object that represents a

     *         connection to the URL

     * @exception SQLException if a database access error occurs

     */

    Connection connect(String url, java.util.Properties info)

        throws SQLException;

    /**

     * Retrieves whether the driver thinks that it can open a connection

     * to the given URL.  Typically drivers will return <code>true</code> if they

     * understand the subprotocol specified in the URL and <code>false</code> if

     * they do not.

     *

     * @param url the URL of the database

     * @return <code>true</code> if this driver understands the given URL;

     *         <code>false</code> otherwise

     * @exception SQLException if a database access error occurs

     */

    boolean acceptsURL(String url) throws SQLException;

    /**

     * Gets information about the possible properties for this driver.

     * <P>

     * The <code>getPropertyInfo</code> method is intended to allow a generic

     * GUI tool to discover what properties it should prompt

     * a human for in order to get

     * enough information to connect to a database.  Note that depending on

     * the values the human has supplied so far, additional values may become

     * necessary, so it may be necessary to iterate though several calls

     * to the <code>getPropertyInfo</code> method.

     *

     * @param url the URL of the database to which to connect

     * @param info a proposed list of tag/value pairs that will be sent on

     *          connect open

     * @return an array of <code>DriverPropertyInfo</code> objects describing

     *          possible properties.  This array may be an empty array if

     *          no properties are required.

     * @exception SQLException if a database access error occurs

     */

    DriverPropertyInfo[] getPropertyInfo(String url, java.util.Properties info)

                         throws SQLException;

    /**

     * Retrieves the driver's major version number. Initially this should be 1.

     *

     * @return this driver's major version number

     */

    int getMajorVersion();

    /**

     * Gets the driver's minor version number. Initially this should be 0.

     * @return this driver's minor version number

     */

    int getMinorVersion();

    /**

     * Reports whether this driver is a genuine JDBC

     * Compliant<sup><font size=-2>TM</font></sup> driver.

     * A driver may only report <code>true</code> here if it passes the JDBC

     * compliance tests; otherwise it is required to return <code>false</code>.

     * <P>

     * JDBC compliance requires full support for the JDBC API and full support

     * for SQL 92 Entry Level.  It is expected that JDBC compliant drivers will

     * be available for all the major commercial databases.

     * <P>

     * This method is not intended to encourage the development of non-JDBC

     * compliant drivers, but is a recognition of the fact that some vendors

     * are interested in using the JDBC API and framework for lightweight

     * databases that do not support full database functionality, or for

     * special databases such as document information retrieval where a SQL

     * implementation may not be feasible.

     * @return <code>true</code> if this driver is JDBC Compliant; <code>false</code>

     *         otherwise

     */

    boolean jdbcCompliant();

}