calling statically and dynamically same method - php

Question

i'm writing a php class that is like an orm.
I have a method, that can be called statically or instanciated, and it must work in both cases.
Can you see what's wrong.
Basically is an object called Model.
When created it creates a table based on the inherited class.
For example:
Podcast extends Model ....
There are some functions like this that needs to be called statically and dynamically.
for example:
$podcastList = Podcast::findAll($db);
I get all podcasts objects from DB without need to have a podcast object instanciated.
But i can also do:
$podcast = new Podcast($db)
$podcastList = $podcast->findAll(); //no db here.... passed before
$db is a class i wrote to make operation on Database. IT simply does with OOP, what mysql_* do with functions. I'm not using PDO, i may use in future, but now i use mysql_* :P
that are the incriminated functions
public static function findAll($db=NULL, $self=NULL) {
if($self == NULL) {
$self = new static($db);
} else {
$self = $this;
}
$self->tableName = "";
$self->db = NULL;
$is_static = !(isset($this) && get_class($this) == __CLASS__);
if($is_static) {
//die(__CLASS__ . "::" . __FUNCTION__ . " CALLED STATICALLY");
if(!$self->db) {
die(__CLASS__ . "::" . __FUNCTION__ . " CALLED STATICALLY AND DB IS NULL");
//It stops here!
}
$self->tableName = $self->genTableName();
} else {
$self->db = $this->db;
$self->tableName = $this->tableName;
}
$query = "SELECT * FROM {$self->tableName}";
$r = $self->db->exec($query);
if(!$r) {
die(__CLASS__ . ":Error " . __FUNCTION__ . " record: " . $self->db->getError());
}
if($self->db->countRows($r) == 0) {
return NULL;
}
$objects = array();
while($row = $self->db->fetch($r, DBF::FETCH_ASSOC)) {
$objectClass = __CLASS__;
$object = new $objectClass($this->db);
//TODO Do it dinamically indipendently of column name
$f = get_class_vars($objectClass);
foreach ($f as $field => $value) {
$chuncks = explode("_", $field);
if($chuncks[0] == "f") {
$object->{$field} = $row[$chuncks[2]];
}
}
$objects[] = $object;
}
return $objects;
}
public function __call($name, $arguments) {
if ($name === 'findAll'){
return static::findAll($arguments, $this);
}
}
Both are part of a class.
Thank you for the help !

Answer 1

There's a lot wrong with this code. More important than your many logic mistakes (why are you setting $self = $this, then $self->db = NULL, then $self->db = $this->db?) is that you are misunderstanding what it means to be able to call static functions dynamically in PHP. The object $this simply doesn't exist in a static method. The call $podcast->findAll() looks non-static, but it's still static.
To do what you want to do, here are some options:
leave the function static and call findAll($this->db, $tablename) as needed
put the function into the db class and call it with parameter tablename
EDIT:
The second in my list is how I would do it. This is because you already have to have a db object in your original example, and there is nothing in particular that makes the function's purpose only suited to Podcast objects and not to, say, any other object representing database rows.
//calling examples:
$podcastlist = $db->findAll('Podcast');
$podcast = new Podcast($db);
$podcastlist = $podcast->findAll();
public class db {
....
function findAll($classname, $tablename=NULL) {
if(!isset($tablename)) {
//let's pretend you put default table names as class constants
$tablename = get_constant($classname.'::DEFAULT_TABLE');
}
$query = "SELECT * FROM {$tableName}";
$r = $this->exec($query);
if(!$r) {
throw new Exception("Error " . __FUNCTION__ . " record: " . $this->getError());
}
if($this->countRows($r) == 0) {
return NULL;
}
$objects = array();
while($row = $this->fetch($r, DBF::FETCH_ASSOC)) {
$object = new $classname($this);
//the following is an easier way to do your original foreach
foreach($row as $field=>$value) {
if(property_exists($classname, "f_".$field)) {
$object->{'f_'.$field} = $value;
}
}
$objects[] = $object;
}
//something you forgot:
return $objects;
}
}
public class Podcast extends Model {
....
public function findAll($tablename=NULL) {
return $this->db->findAll(class_name($this), $tablename);
}
}