39 Advanced Java Servlet Tutorial | Java Web application both client and server side form validatio

Advanced Java Servlet Tutorial #Example Java Web application for both client Side and server side form validation having the ability to execute server-side form validation only when client side form validation are not done!
Cases:
1) If client Side Validation are not done then Server side Validation must be done.
OR
2) If Client side are validation are done then server side validation should not be done.


Note: In "VoterApp" both client side & server side form validation are enabled but server side form validation will be executed only when client side form validation are not done.

Deployment Directory Struture (VoterApp):

VoterApp
--------
|-------input.html
|-------validation.js
|-------WEB-INF
|-----web.xml
|-----classes
|-------VoterServ.java
|-------p1
|-----VoterServ.class

Before Compiling VoterServ.java file do confirm that servlet-api.jar is placed in environment variable/classpath.

Request URL:
http://localhost:2020/11VoterApp/input.html

- To make javascipt code as the reusable code in multiple form page & to hide javascript from end users through Right click on page select option as "View Page Source" option of browser window, its not recommended to write JavaScript code directly in .html file, that means write this javascipt code in separate file like .js (Ex: bootstrap.js/ Validation.js) file and link that file with multiple .html file.

- return statement without value stop the execution of current method definition & returns the control to the called method.