<?php
/*
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the MIT license. For more information, see
 * <http://www.doctrine-project.org>.
 */

namespace Doctrine\ORM\Query\Expr;

/**
 * Expression class for DQL from
 *
 * 
 * @link    www.doctrine-project.org
 * @since   2.0
 * @author  Guilherme Blanco <guilhermeblanco@hotmail.com>
 * @author  Jonathan Wage <jonwage@gmail.com>
 * @author  Roman Borschel <roman@code-factory.org>
 */
class From
{
    /**
     * @var string
     */
    protected $from;

    /**
     * @var string
     */
    protected $alias;

    /**
     * @var string
     */
    protected $indexBy;

    /**
     * @param string $from      The class name.
     * @param string $alias     The alias of the class.
     * @param string $indexBy   The index for the from.
     */
    public function __construct($from, $alias, $indexBy = null)
    {
        $this->from    = $from;
        $this->alias   = $alias;
        $this->indexBy = $indexBy;
    }

    /**
     * @return string
     */
    public function getFrom()
    {
        return $this->from;
    }

    /**
     * @return string
     */
    public function getAlias()
    {
        return $this->alias;
    }

    /**
     * @return string
     */
    public function getIndexBy()
    {
        return $this->indexBy;
    }

    /**
     * @return string
     */
    public function __toString()
    {
        return $this->from . ' ' . $this->alias .
                ($this->indexBy ? ' INDEX BY ' . $this->indexBy : '');
    }
}