Contrast with JavaScript HTML Formsto invoke Java Server Pages Structure of Forms Query strings Java Server Pages Sent From Browser To Serverfor JSP

JSPJava programs run on/executed by server Javascript- executed by browser – gives dynamic effects HTML - used by browser - to define content & layout - At request of client - Results returned to client in HTML page versus:

JavaScript R-R Request HTML page retrieves html page returns page to client client (browser) executes Java script containing JavaScript CLIENT-SIDE SCRIPT server Apache Tomcat Request-Response Protocol

Java Server Page R-R client Requests JSP page server returns HTML + Results browser displays page executes JSP code Compiled first time only Handles extensions like.jsp or.html differently compiles JSP code retrieves page from storage SERVER-SIDE SCRIPT replaces JSP with results

HTML Forms User enters data. Browser sends data To server that sent Form. Form identifies server program that processes the data. name age submit Input fields Triggers transmission of data to server Submit button Form

HTML Form Please enter data HTML for Form: Source: Chapter03/example6a.html Program on server Submits request to server Sends data in query-string Variable names Name: Major:

From: Browser TO: Server ? firstName=aaa&major=zzz WHEREWHOWHAT JSP program - on server - requested by HTML Form Data for JSP program Query string Triggered by Form

Using HTML Formsto invoke Java Server Pages Structure of HTML Forms Structure of Query stringsSent to Server from Browseras JSP data Preview