Charset.php

<?php
class ZendDbSchema_Validate_Db_Schema_Database_Mysql_Charset
    extends Zend_Validate_Abstract
{
    const ENGINE_EMPTY = 'databaseEngineEmpty';
    const INVALID      = 'databaseEngineInvalid';
    const NOT_AVAIBLE  = 'databaseEngineNotAvaible';

    protected $_messageTemplates = array(
        self::ENGINE_EMPTY => "Database engine can not be empty",
        self::INVALID      => 'Engine %value% is not valid engine type',
        self::NOT_AVAIBLE  => "Engine %value% is not avaible"
    );

    public function isValid($value)
    {
        $schema = null;
        if ($value instanceof ZendDbSchema_Db_Schema_Database) {
            $schema = $value;
            $value = $schema->getName();
        }

        if (empty($value)) {
            $this->_error(self::NAME_EMPTY);
            return false;
        }
        return true;
    }
}