Steps To Develop Web Application using Java
2)
servlet components are web components we need servlet API to create web
components, servlet API is not available inside JRE, so we need to add servlet API
explicitly.
select created Java project and add servlet API, from external jar location, it is available inside configure build path.
3) servlets
program executed inside servlet container, servlet container available inside
web server like tomcat so we should add server to Java class path.
after adding servlet API and server(tomcat), our setup is almost ready.
4) write code.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| package com.smarttechguides; | |
| import java.io.IOException; | |
| import java.io.PrintWriter; | |
| import javax.servlet.GenericServlet; | |
| import javax.servlet.ServletRequest; | |
| import javax.servlet.ServletResponse; | |
| public class HelloWorld extends GenericServlet { | |
| @Override | |
| public void service(ServletRequest request, ServletResponse response) throws IOException { | |
| PrintWriter writer = response.getWriter(); | |
| writer.print("Hello World.."); | |
| writer.close(); | |
| } | |
| } |
here service method is request processing method, it is an abstract method available inside GenericServlet class. we are writing our own business logic inside this method.
5) create Html file for displaying result on browser.
index.html
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| <html> | |
| <head> | |
| <meta charset="ISO-8859-1"> | |
| <title>hello world</title> | |
| </head> | |
| <body> | |
| <h1>print helloo...</h1> | |
| </body> | |
| </html> |
6) Finally, we need to map our servlet program with URL pattern inside WEB-INF.
because our tomcat server looking the servlet component with its mapping URLs.
web.xml
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| <?xml version="1.0" encoding="UTF-8"?> | |
| <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" | |
| xmlns="http://java.sun.com/xml/ns/javaee" | |
| xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" | |
| id="WebApp_ID" version="3.0"> | |
| <display-name>PRINT HELLO</display-name> | |
| <welcome-file-list> | |
| <welcome-file>index.html</welcome-file> | |
| </welcome-file-list> | |
| <servlet> | |
| <servlet-name>component</servlet-name> | |
| <servlet-class>com.smarttechguides.HelloWorld</servlet-class> | |
| </servlet> | |
| <servlet-mapping> | |
| <servlet-name>component</servlet-name> | |
| <url-pattern>/urlname</url-pattern> | |
| </servlet-mapping> | |
| </web-app> |
No comments:
Post a Comment