//====================================================================
// ConnectionManager.java
//====================================================================

package com.evident.database;

import java.sql.*;
import javax.sql.*;

/**
* Manages connections served by a JDBC DataSource, ensuring that
* each connection is released after its use.
*/
public class ConnectionManager {

    /** Manages database connections. */
    protected DataSource source;

    /**
    * Constructs a new ConnectionManager.
    * @param dataSource manages database connections.
    */
    public ConnectionManager( DataSource dataSource ) {
        source = dataSource;
    }

    /**
    * Obtains a connection for a (usage) and frees the connection when
    * finished. Rolls back any uncommitted changes if a SQL exception is
    * thrown during the (usage) of the connection.
    * @param usage a database connection usage.
    * @exception java.sql.SQLException if an exception is thrown during the
    * connection (usage).
    */
    public Object connectUsing( ConnectionUsage usage ) {
		boolean autoCommit = true;
        Connection connection = null;
        try {
            connection = source.getConnection();
			usage.prepare( connection );
            return usage.use( connection );
        } catch( SQLException e ) {
			usage.rollback( connection );
            e.printStackTrace();
            return null;
        } finally {
			usage.release( connection );
        }
    }
}