<?php
interface Permissions {
public function isReadable();
public function isWritable();
}
class ReadOnly implements Permissions {
public function isReadable() {
return true;
}
public function isWritable() {
return false;
}
}
class WriteOnly implements Permissions {
public function isReadable() {
return false;
}
public function isWritable() {
return true;
}
}
class ReadWrite implements Permissions {
public function isReadable() {
return true;
}
public function isWritable() {
return true;
}
}
class Field {
private $name;
private $permissions;
public function __construct($name, Permissions $permissions = null) {
$this->name = (string) $name;
$this->permissions = $permissions ?: new ReadOnly;
}
public function getName() {
return $this->name;
}
public function isReadable() {
return $this->permissions->isReadable();
}
public function isWritable() {
return $this->permissions->isWritable();
}
}
$a = new Field('a');
var_dump($a->isReadable());
var_dump($a->isWritable());
$b = new Field('b', new ReadWrite);
var_dump($b->isReadable());
var_dump($b->isWritable());