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ReflectionClass::isInstantiable

(PHP 5, PHP 7, PHP 8)

ReflectionClass::isInstantiable — Checks if the class is instantiable

Description

public ReflectionClass::isInstantiable(): bool

Parameters

This function has no parameters.

Return Values

Returns [true](reserved.constants.php#constant.true) on success or [false](reserved.constants.php#constant.false) on failure.

Examples

Example #1 ReflectionClass::isInstantiable() example

`<?php
class C { }

interface

iface {
function f1();
}

class

ifaceImpl implements iface {
function f1() {}
}

abstract class

abstractClass {
function f1() { }
abstract function f2();
}

class

D extends abstractClass {
function f2() { }
}

trait

T {
function f1() {}
}

class

privateConstructor {
private function __construct() { }
}$classes = array(
"C",
"iface",
"ifaceImpl",
"abstractClass",
"D",
"T",
"privateConstructor",
);

foreach( classesasclasses as classesasclass ) { reflectionClass=newReflectionClass(reflectionClass = new ReflectionClass(reflectionClass=newReflectionClass(class);
echo "Is $class instantiable? ";
var_dump($reflectionClass->isInstantiable());
}?>`

The above example will output:

Is C instantiable? bool(true) Is iface instantiable? bool(false) Is ifaceImpl instantiable? bool(true) Is abstractClass instantiable? bool(false) Is D instantiable? bool(true) Is T instantiable? bool(false) Is privateConstructor instantiable? bool(false)

Found A Problem?

shaun at slickdesign dot com dot au ¶

7 years ago

`` An example missing from the documentation is that ReflectionClass::isInstantiable will also return false for traits, as well as interfaces and abstract classes.

As for classes with private constructors, it is still possible to create an instance by either bypassing the constructor using ReflectionClass::newInstanceWithoutConstructor, or by ensuring the class has a method which can create a new instance.

The same is also true for protected constructors, however, the class can be instantiated from either parent or child methods, depending on where the constructor is defined.

``