Using PHP with Java - Beanie Baby (
Page 7 of 7 )
Finally, how about
connecting PHP up to a Java Bean? Here's the Bean, a simple
Celsius-to-Fahrenheit-to-Celsius converter:
temperature.zipThe Bean exposes the following
methods:
getCelsius() - get the current value of the Celsius
property
getFahrenheit() - get the current value of the Fahrenheit
property
setCelsius(num) - set the current value of the Celsius property
to num
setFahrenheit(num) - set the current value of the Fahrenheit
property to num
convertCelsiusToFahrenheit(value) - convert Celsius value
to Fahrenheit
convertFahrenheitToCelsius(value) - convert Fahrenheit
value to Celsius
And here's a PHP script which combines user input with
the Temperature Bean to perform temperature conversion:
<html>
<head><basefont face="Arial"></head>
<body>
<h2>Temperature Converter</h2>
<?php
if($submit)
{
// data type conversion
setType($temp,"integer");
$myClass = new Java("Temperature");
if($units == "celsius" && $temp != "")
{
// use the Celsius functions
$myClass->setCelsius($temp);
// print result
echo $myClass->getCelsius()," <sup>o</sup> Celsius is
",$myClass->convertCelsiusToFahrenheit($myClass->getCelsius()),"
<sup>o</sup> Fahrenheit.";
}
else if($units == "fahrenheit" && $temp != "")
{
// use the Fahrenheit functions
$myClass->setFahrenheit($temp);
// print result
echo $myClass->getFahrenheit() , " <sup>o</sup>
Fahrenheit is ",
$myClass->convertFahrenheitToCelsius($myClass->getFahrenheit()) , "
<sup>o</sup> Celsius.";
}
else
{
echo "Please enter a valid temperature and scale";
}
}
else
{
?>
<form action="<? echo $PHP_SELF; ?>" method="post">
<input type ="text" name="temp" size="4" maxlength="4">
<select name="units">
<option value="celsius">Celsius</option>
<option value="fahrenheit">Fahrenheit</option>
</select>
<input type ="submit" name="submit" value="Convert">
</form>
<?
}
?>
</body>
</html>
This script consists of two parts: the form which allows the
user to select a temperature scale and enter a tempterature value, and the form
processor which actually uses the Bean to perform the conversion and display the
result.
Here's what the form looks like:
Once this form has been submitted, an object is
instantiated from the Temperature class, and the information provided by the
user is used to perform temperature conversion using the Bean methods described
above. The result is then displayed to the user.
Here's what the result
looks like:
Note that it's necessary to
convert the type of the form variable $temp from string to integer in order to
make it compatible with the arguments expected by the Bean - this data type
conversion is one of the important issues you will face when accessing Java
classes through PHP.
And that's about it for the moment. In case you'd
like to learn more, take a look at the following links:
The PHP manual's
Java pages, at
http://www.php.net/manual/en/ref.java.phpO'Reilly's
PHP and Java tutorial on O'Reilly ONLamp.com, at
http://www.onlamp.com/pub/a/php/2001/06/14/php_jav.htmlPHPBuilder's
PHP and Java tutorial, at
http://www.phpbuilder.com/columns/marknold20001221.php3See
you soon! Note: All examples in this article have been tested on Linux/i586 with
JDK 1.3.0, Apache 1.3.20 and PHP 4.1.1. Examples are illustrative only, and are
not meant for a production environment. Melonfire provides no warranties or
support for the source code described in this article. YMMV!
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