Error message Strict standards: Non-static method should not be called statically in php

Question

I have the following php. However when I see the index.php I get the following error message.

Strict standards: Non-static method Page::getInstanceByName() should not be called statically in /var/www/webworks/index.php on line 12

I am hoping someone can tell me how to fix the problem.

index.php

// { common variables and functions
include_once('ww.incs/common.php');
$page=isset($_REQUEST['page'])?$_REQUEST['page']:'';
$id=isset($_REQUEST['id'])?(int)$_REQUEST['id']:0;
...

// { get current page id
if(!$id){
    if($page){ // load by name
        $r=Page::getInstanceByName($page);
        if($r && isset($r->id))$id=$r->id;
    }
    if(!$id){ // else load by special
        $special=1;
        if(!$page){
            $r=Page::getInstanceBySpecial($special);
            if($r && isset($r->id))$id=$r->id;
        }
    }
}

// { load page data
if($id){
    $PAGEDATA=(isset($r) && $r)?$r : Page::getInstance($id);
}
else{
    echo '404 thing goes here';
    exit;
}
...
...

ww.incs/common.php

<?php
require dirname(__FILE__).'/basics.php';
...
...

ww.incs/basics.php

session_start();
if(!function_exists('__autoload')){
    function __autoload($name) {
        require $name . '.php';
    }
}
...
...

Page.php

class Page{
    static $instances             = array();
    static $instancesByName     = array();
    static $instancesBySpecial   = array();
    function __construct($v,$byField=0,$fromRow=0,$pvq=0){
        # byField: 0=ID; 1=Name; 3=special
        if (!$byField && is_numeric($v)){ // by ID
            $r=$fromRow?$fromRow:($v?dbRow("select * from pages where id=$v limit 1"):array());
        }
        else if ($byField == 1){ // by name
            $name=strtolower(str_replace('-','_',$v));
            $fname='page_by_name_'.md5($name);
            $r=dbRow("select * from pages where name like '".addslashes($name)."' limit 1");
        }
        else if ($byField == 3 && is_numeric($v)){ // by special
            $fname='page_by_special_'.$v;
            $r=dbRow("select * from pages where special&$v limit 1");
        }
        else return false;
        if(!count($r || !is_array($r)))return false;
        if(!isset($r['id']))$r['id']=0;
        if(!isset($r['type']))$r['type']=0;
        if(!isset($r['special']))$r['special']=0;
        if(!isset($r['name']))$r['name']='NO NAME SUPPLIED';
        foreach ($r as $k=>$v) $this->{$k}=$v;
        $this->urlname=$r['name'];
        $this->dbVals=$r;
        self::$instances[$this->id] =& $this;
        self::$instancesByName[preg_replace('/[^a-z0-9]/','-',strtolower($this->urlname))] =& $this;
        self::$instancesBySpecial[$this->special] =& $this;
        if(!$this->vars)$this->vars='{}';
        $this->vars=json_decode($this->vars);
    }
    function getInstance($id=0,$fromRow=false,$pvq=false){
        if (!is_numeric($id)) return false;
        if (!@array_key_exists($id,self::$instances)) self::$instances[$id]=new Page($id,0,$fromRow,$pvq);
        return self::$instances[$id];
    }
    function getInstanceByName($name=''){
        $name=strtolower($name);
        $nameIndex=preg_replace('#[^a-z0-9/]#','-',$name);
        if(@array_key_exists($nameIndex,self::$instancesByName))return self::$instancesByName[$nameIndex];
        self::$instancesByName[$nameIndex]=new Page($name,1);
        return self::$instancesByName[$nameIndex];
    }
    function getInstanceBySpecial($sp=0){
        if (!is_numeric($sp)) return false;
        if (!@array_key_exists($sp,$instancesBySpecial)) $instancesBySpecial[$sp]=new Page($sp,3);
        return $instancesBySpecial[$sp];
    }

question from:https://stackoverflow.com/questions/65651427/php7-4-non-static-method-should-not-access-as-static

Answer 1

Your methods are missing the static keyword. Change

function getInstanceByName($name=''){

to

public static function getInstanceByName($name=''){

if you want to call them statically.

Note that static methods (and Singletons) are death to testability.

Also note that you are doing way too much work in the constructor, especially all that querying shouldn't be in there. All your constructor is supposed to do is set the object into a valid state. If you have to have data from outside the class to do that consider injecting it instead of pulling it. Also note that constructors cannot return anything. They will always return void so all these return false statements do nothing but end the construction.