PHP - Crear un nuevo ejemplo de clase dentro de otra clase

<?
class Class_One {
   
    var $name;
   
    function __construct($my_string) {
        $this->name = $my_string;
        echo 'Hello ' . $this->name;
    }
   
    function function_one() {
        echo 'Hello World';
    }
 
}
 
class Class_Two {
 
    function __construct() {
        $new_class_instance = new Class_One('Joan');
    }
}
?>

<?php
class one
{
    function two()
    {
        return 'Blue dog!';
    }
}

class three extends one
{
    function __construct()
    {

    }
}

$class = new three();

$class->two();
?>

 
public class ClassOne{
  public void SayHello(String name){
    Console.WriteLine(this.GetHello(name));
  }
 
  public String GetHello(String name){
    return String.Format("Hello: {0}",name);
  }
}
 
public class ClassTwo{
  private ClassOne _classOne = new ClassOne();
  public void SayHelloAndGreeting(String name, String greeting){
    Console.WriteLine(GetHelloAndGreeting(name, greeting));
  }
 
  public String GetHelloAndGreeting(String name, String greeting){
   return String.Format("{0} - {1}", _classOne.GetHello(name), greeting);
  }
  public ClassOne ClassOneInstance{get{return _classOne;}}
}
 
//Usage
public static void Main(String[] args){
  ClassTwo classTwo = new ClassTwo();
  classTwo.SayHelloAndGreeting("Jimmini Cricket", "Just greeting you");
  classTwo.ClassOneInstance.SayHello("Jimmini Cricket");
}
 

<?php
class Class_One {
   
    var $name;
   
    function __construct($my_string) {
        $this->name = $my_string;
        echo 'Hello ' . $this->name;
    }
   
    function function_one() {
        echo 'Hello World';
    }
 
}
 
class Class_Two {
 
    function __construct() {
        //$new_class_instance = new Class_One('Joan');
        Class_One::function_one();
    }
   
    function haha() {
        Class_One::function_one();
    }
}
$Test = new Class_Two(); //in constructor
$Test->haha(); // in method, you can name it function_one if you want
Class_One::function_one(); //this works also =)
?>

<?php
 
/*
    Utility class #1
*/
class hammer
{
    public function bang(){
        echo 'Bang! ';
        return;
    }
    public function pry(){
        echo 'Pry! ';
        return;
    }
}
 
/*
    Utility class #2
*/
class screwdriver
{
    public function loosen(){
        echo 'Loosen! ';
        return;
    }
    public function tighten(){
        echo 'Tighten! ';
        return;
    }
}
 
/*
    Implementer of utility classes
*/
class handyman
{
    /*
        A place to keep our utilities
    */
    public $toolbelt = array();
 
    public function __construct($tools = array())
    {
        foreach($tools as $tool)
        {
            /*
                http://www.php.net/get_class
                Make sure we only have one of any given tool, does not _have_ to be this way
            */
            $this->toolbelt[get_class($tool)] = $tool;
        }
        return $this;
    }
 
    /*
        http://www.php.net/manual/en/language.oop5.overloading.php#language.oop5.overloading.methods
    */
    public function __call($method_name, $args)
    {
        foreach($this->toolbelt as $tool)
        {
            /*
                http://www.php.net/is_callable
                See if the utility object has a callable method matching the one asked for
            */
            if(is_callable(array($tool, $method_name)))
            {
                /*
                    http://www.php.net/call_user_func_array
                    Forward the method call to the utility object along with the arguments
                */
                return call_user_func_array(array($tool, $method_name), $args);
            }
        }
        /*
            http://www.php.net/trigger_error
        */
        trigger_error("Do not have a tool that can $method_name!", E_USER_ERROR);
    }
}
 
$me = new handyman(array(new hammer(), new screwdriver()));
 
$me->bang();
$me->pry();
$me->tighten();
$me->loosen();
$me->gitrdone();
 
?>