<?php
// require the files needed for this test
require_once ("../DCIObject.php");
require_once ("../DCIException.php");
require_once ("../Context.php");
interface rMoneySource {
function Withdraw($amount);
}
interface rMoneySink {
function Deposit($amount);
}
class rMoneySourceActions {
static function TransferFunds(rMoneySource $self, rMoneySink $dest, $amount) {
if ($self->Withdraw($amount))
$dest->Deposit($amount);
}
}
/**
* A base Account object. It's a dumb model, capable only
* of increasing and decreasing its balance. We can use
* roles to make different Account objects interact with each
* other.
*
* Contexts are "use cases". They call role methods to implement interactivity
* Role methods are "algorithms". They call various object methods to perform a task
*/
class Account
extends DCIObject
implements rMoneySource, rMoneySink {
protected $balance;
function __construct($initial_balance) {
parent::__construct();
$this->balance = $initial_balance;
}
function Withdraw($amount) {
if ($amount <= $this->balance) {
$this->balance -= $amount;
return $amount;
}
else
throw new DCIException("Insufficient Funds","Tried to withdraw $amount<br />{$this->balance} available.");
}
function Deposit($amount) {
$this->balance += $amount;
}
function GetBalance() { return $this->balance; }
}
class FeeAccount
extends Account {
function Deposit($amount) {
$this->balance += ($amount * .9);
}
}
/**
* The example code-- implemented as a context
*/
class TransferCtx extends Context {
function Execute(rMoneySource $source, rMoneySink $sink, $amount) {
$source->TransferFunds($sink,$amount);
}
}
/**
* Run the context and display the change in values
*/
$checking = new Account(1000);
$savings = new FeeAccount(500);
echo "<h3>Initialization Test:</h3>";
echo "Checking Account: $" . $checking->GetBalance() . "<br />";
echo "Savings Account: $" . $savings->GetBalance() . "<br /><br />";
$tm_ctx = new TransferCtx();
$tm_ctx->Execute($checking, $savings, 500);
echo "<h3>Transaction Test:</h3>";
echo "Checking Account: $" . $checking->GetBalance() . "<br />";
echo "Savings Account: $" . $savings->GetBalance() . "<br /><br />";
echo "<h3>Insufficient Funds Exception Test</h3>";
echo "Insufficient Funds Test:<br />";
$tm_ctx->Execute($checking, $savings, 1000);
?>
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