Like PHP, a JSP or Java Server Page file creates a website from the server, allowing more complicated functions than a basic HTML page. PHP and JSP files are text-based, so if your server generates a PHP file that should be displayed as a JSP, switching it over is easy. The browser displays a webpage based on the extension, so even if the code would be best displayed in JSP form, if the extension is PHP the browser displays it that way.
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Right-click the PHP file on your hard drive.
Select "Open with" and click "Notepad."
Select "Save As" from the "File" menu.
Click "Java Server Page (*.jsp)" from the format menu and click "Save." The code is now a JSP file and will be displayed on your website as such.