final
PHP 5 introduces the final keyword, which prevents child classes from overriding a method by prefixing the definition with final. If the class itself is being defined final then it cannot be extended.
Example #1 Final methods example
<?php
class?BaseClass?{
???public?function?test()?{
???????echo?"BaseClass::test()?called\n";
???}
???
???final?public?function?moreTesting()?{
???????echo?"BaseClass::moreTesting()?called\n";
???}
}
class?ChildClass?extends?BaseClass?{
???public?function?moreTesting()?{
???????echo?"ChildClass::moreTesting()?called\n";
???}
}
//?Results?in?Fatal?error:?Cannot?override?final?method?BaseClass::moreTesting()
?>Example #2 Final class example
<?php
final?class?BaseClass?{
???public?function?test()?{
???????echo?"BaseClass::test()?called\n";
???}
???//?Here?it?doesn't?matter?if?you?specify?the?function?as?final?or?not
???final?public?function?moreTesting()?{
???????echo?"BaseClass::moreTesting()?called\n";
???}
}
class?ChildClass?extends?BaseClass?{
}
//?Results?in?Fatal?error:?Class?ChildClass?may?not?inherit?from?final?class?(BaseClass)
?>Note: Properties cannot be declared final, only classes and methods may be declared as final.
← Magic Methods
Object Cloning →
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