Magento 1.8 Database – Problems Saving Data to DB – Fatal Error: Cannot Call Abstract Method

Creating a custom module Im facing many problems saving data to DB. My code look like this:

config.xml:

<modules>
    <Pricebinc_Shipping>
        <version>0.1.0</version>
    </Pricebinc_Shipping>
</modules>
<global>
    <models>
        <shipping>
            <class>Pricebinc_Shipping_Model</class>
            <resourceModel>shipping_resource</resourceModel>
        </shipping>
        <shipping_resource>
            <class>Pricebinc_Shipping_Model_Resource</class>
            <entities>
                <shipmentlist>
                    <table>shipping_shipmentlist</table>
                </shipmentlist>
            </entities>
        </shipping_resource>
    </models>
    <resources>
        <shipping_setup>
            <setup>
                <module>Pricebinc_Shipping</module>
            </setup>
            <connection>
                <use>core_setup</use>
            </connection>
        </shipping_setup>
        <shipping_write>
            <connection>
                <use>core_write</use>
            </connection>
        </shipping_write>
        <shipping_read>
            <connection>
                <use>core_read</use>
            </connection>
        </shipping_read>
    </resources>

In Model I have three files. a- model/shipmentlist.php

class Pricebinc_Shipping_Model_Shipmentlist extends Mage_Core_Model_Abstract {

   public function _construct()
     {
         parent::_construct();
         $this->_init('shipping/shipmentlist');
     } 
}

Model/Resource/Shipmentlist.php with code:

class Pricebinc_Shipping_Model_Resource_Shipmentlist extends Mage_Core_Model_Resource_Db_Abstract
{
    protected function _construct()
    {
        parent::_construct();
        $this->_init('shipping/shipmentlist', 'autoid');
    }
}

autoid is my primary key.

and Model/Resource/Shipmentlist/collection.php with code:

class Pricebinc_Shipping_Model_Resource_Shipmentlist_Collection extends Mage_Core_Model_Resource_Db_Collection_Abstract
{
    protected function _construct()
    {
        parent::_construct();
        $this->_init('shipping/shipmentlist');
    }
}

finally I have a controller and trying to save data using the following code:

public function newAwbAction()
{
            $shipcontact = ''.$this->getRequest()->getPost('shipContact');
            $shipper = ''.$this->getRequest()->getPost('shipper');
            $shipaddr1 = ''.$this->getRequest()->getPost('shipAddr1');
            $shipaddr2 = ''.$this->getRequest()->getPost('shipAddr2');

            $magentoShippingModel = Mage::getModel('shipping/shipmentlist');
            $magentoShippingModel->setData('shipContact', $shipcontact);
            $magentoShippingModel->setData('shipper', $shipper);
            $magentoShippingModel->setData('shipAddr1', $shipaddr1);
            $magentoShippingModel->setData('shipAddr2', $shipaddr2);
            $magentoShippingModel->save();

}

Im receiving the following error ->
Fatal error: Cannot call abstract method Mage_Core_Model_Resource_Abstract::_construct() in C:\Zend\Apache2\htdocs\app\code\local\Pricebinc\Shipping\Model\Resource\Shipmentlist.php on line 6

If I change Model/Resource/Shipmentlist.php to

class Pricebinc_Shipping_Model_Resource_Shipmentlist extends Mage_Core_Model_Resource_Db_Abstract
{
    protected function _construct()
    {
        $mainTable = 'shipping_shipmentlist'; // check the node in the config.xml
        $idFieldName = 'autoid'; // whatever the column is named.
        $this->_init($mainTable, $idFieldName);
    }
}

I receive the following error ->
Fatal error: Call to a member function getConnection() on a non-object in C:\Zend\Apache2\htdocs\app\code\core\Mage\Core\Model\Resource\Db\Abstract.php on line 322

any help appreciated.