数据源架构模式之行数据入口

<?php
/**
 * 行数据入口类
 */
class OrderGateway {
    /*定义元数据映射*/
    private $_name;
    private $_id;
 
    public function __construct($id, $name) {
        $this->setId($id);
        $this->setName($name);
    }
 
    public function getName() {
        return $this->_name;
    }
 
    public function setName($name) {
        $this->_name = $name;
    }
 
    public function getId() {
        return $this->_id;
    }
 
    public function setId($id) {
        $this->_id = $id;
    }
 
    /**
     * 入口类自身拥有更新操作
     */
    public function update() {
        $data = array(&#39;id&#39; => $this->_id, &#39;name&#39; => $this->_name);
 
        $sql = "UPDATE order SET ";
        foreach ($data as $field => $value) {
            $sql .= "`" . $field . "` = &#39;" . $value . "&#39;,";
        }
        $sql = substr($sql, 0, -1);
        $sql .= " WHERE id = " . $this->_id;
        return DB::query($sql);
    }
 
    /**
     * 入口类自身拥有插入操作
     */
    public function insert() {
        $data = array(&#39;name&#39; => $this->_name);
 
        $sql = "INSERT INTO order ";
        $sql .= "(`" . implode("`,`", array_keys($data)) . "`)";
        $sql .= " VALUES(&#39;" . implode("&#39;,&#39;", array_values($data)) . "&#39;)";
 
        return DB::query($sql);
    }
 
    public static function load($rs) {
        /* 此处可加上缓存 */
        return new OrderGateway($rs[&#39;id&#39;] ? $rs[&#39;id&#39;] : NULL, $rs[&#39;name&#39;]);
    }
 
}
 
/**
 * 为了从数据库中读取信息，设置独立的OrderFinder娄。
 */
class OrderFinder {
    public function find($id) {
        $sql = "SELECT * FROM order WHERE id = " . $id;
        $rs = DB::query($sql);
 
        return OrderGateway::load($rs);//这里返回的行对象
    }
 
    public function findAll() {
        $sql = "SELECT * FROM order";
        $rs = DB::query($sql);
 
        $result = array();
        if (is_array($rs)) {
            foreach ($rs as $row) {
                $result[] = OrderGateway::load($row);
            }
        }
 
        return $result;
    }
 
}
 
class DB {
 
    /**
     * 这只是一个执行SQL的演示方法
     * @param string $sql   需要执行的SQL
     */
    public static function query($sql) {
        echo "执行SQL: ", $sql, " <br />";
    }
}
 
/**
 * 客户端调用
 */
class Client {
    public static function main() {
        header("Content-type:text/html; charset=utf-8");
 
        /* 写入示例 */
        $data = array(&#39;name&#39; => &#39;start&#39;);
        $order = OrderGateway::load($data);
        $order->insert();
 
        /* 更新示例 */
        $data = array(&#39;id&#39; => 1, &#39;name&#39; => &#39;stop&#39;);
        $order = OrderGateway::load($data);
        $order->setName(&#39;xxxxxx&#39;);
        $order->update();
 
        /* 查询示例 */
        $finder = new OrderFinder();
        $order = $finder->find(1);
        echo $order->getName();
    }
}
 
Client::main();
?>