The Java extension is an extremely exciting tool. By learning how to use this module, you can extend PHP by the power of all available Java classes. To show you the basics of the Java extension, this article will cover installation and a few code examples of using PHP and Java together.

I have tried on Windows Installation. Need to check on linux

The following configuration has been tested with Apache 1.3.12, PHP 4.0.3 binaries from www.php4win.de plus the 4.0.3 Zend Optimiser and JDK 1.2.2 from java.sun.com. I have also tested this configuration with older versions of the JDK and windows 2000 later.

Step 1: Install the JDK. This is fairly simple, as the JDK installs without many questions. It might be useful to check your environment (autoexec.bat in Windows 9x and System under Control Panel in NT) and make sure the jdk1.x.x\bin directory is in your path.

This will make compiling your Java Classes easier. On Win9x add

to your autoexec.bat. On NT add

to the end of the PATH environment variable. It is also important to note in your autoexec.bat file, the PHP Java extension ignores the JAVA_HOME and CLASSPATH set up in the environment. This is important because these items must be set correctly in your php.ini file for the Java extension to work.

Step 2: Modifying your php.ini. You need to add something similiar to your php.ini file.

[java]
extension=php_java.dll
java.library.path=c:\web\php4\extensions\
java.class.path="c:\web\php4\extensions\jdk1.2.2\php_java.jar;c:\myclasses"

Typically, people put the extension=php_java.dll directive with the rest of the extensions, but it can sit happily under [java]. The java.library.path must be set in the location of the php_java.dll, and java.class.path must include the location of php_java.jar. The java.class.path should also include the path to other classes you may wish to use (note the double quotes!). In these examples, we will be talking about c:\myclasses. You should also note that the single period is ignored by PHP and Java. As far as we know, you cannot set PHP to look in the current directory for its Java classes.

Step 3: Testing your Install. Now, you’re ready to go. Create a PHP file that looks something like this:

<?php

  $system = new Java("java.lang.System");
  print "Java version=".$system->getProperty("java.version")." <br>\n";
  print "Java vendor=".$system->getProperty("java.vendor")." <p>\n\n";
  print "OS=".$system->getProperty("os.name")." ".
              $system->getProperty("os.version")." on ".
              $system->getProperty("os.arch")." <br>\n";

  $formatter = new Java("java.text.SimpleDateFormat","EEEE,
	MMMM dd, yyyy 'at' h:mm:ss a zzzz");
  print $formatter->format(new Java("java.util.Date"))."\n";

?>

If you have correctly installed everything, you should see some results like:

Java version=1.2.2
Java vendor=Sun Microsystems Inc.
OS=Windows 2000 4.10 on x86
Wednesday, June 18, 2009 at 10:22:45 AM India Standard Time