This post
highlights the difference between JSP and Servlet technologies.
Java
Servlet technology and JavaServer Pages (JSP pages) are server-side
technologies that become the standard way to develop web applications.
Most
importantly, if used effectively by following best practices, servlets and JSP
pages help separate presentation from content.
Servlets
support a request and response programming model. When a client sends a request
to the server, the server sends the request to the servlet. The servlet then
constructs a response that the server sends back to the client. When a client
request is made, the service method is called and passed a request and response
object. The servlet first determines whether the request is a GET or POST
operation. It then calls one of the following methods: doGet or doPost. The
doGet method is called if the request is GET, and doPost is called if the
request is POST.
Adding
more, Servlets are Java classes that can generate dynamic HTML content using
print statements.
out.println("<html><head><title>"+thisIsMyMessage+"</title></head>");
So, you
can embed HTML code into Java code.
A JSP
page is basically a web page with traditional HTML and bits of Java code. The
file extension of a JSP page is .jsp rather than .html or .htm, which tells the
server that this page requires special handling that will be accomplished by a
server extension. When a JSP page is called, it will be compiled (by the JSP
engine) into a Java servlet.
Importantly,
we can add dynamic content or Java Code inside an HTML Tag using JSP’s
Scriplets.
And
scriptlets, this is code fragments like:
<% String message = "Hello !"%>
<H2> Welcome and <%=message%>! </H2>
So, you can embed Java code into HTML code.
|
SERVLET
|
JSP
|
|
A servlet
is a server-side program and written purely on Java.
|
JSPs are HTML pages with .jsp
extension. JSP’s are extension of servlets to minimize the effort of
developers to write User Interfaces using Java programming.
|
|
Executes
inside a Web server, such as Tomcat
|
A JSP program is
compiled into a Java servlet before execution. Once compiled into a servlet,
it's life cycle will be same as of servlet. But, JSP has it's own API for the
lifecycle.
|
|
Servlets
run faster than JSP
|
JSP runs
slower because it has the transition phase for converting from JSP page to a
Servlet file.
|
|
Servlet has
the life cycle methods init(), service() and destroy()
|
JSP has the life cycle
methods of jspInit(), _jspService() and jspDestroy()
|
|
Difficult to
write as one has to write HTML tags within quotes(“<HTML>”) in Java.
Mixing HTML content inside Java is tedious.
|
Easier to
write than servlets as it is similar to HTML
|
|
Written in
Java, with a few additional APIs specific to this kind of processing. Since
it is written in Java, it follows all the Object Oriented programming
techniques.
|
One of the key
advantage is we can build custom tags using JSP API , which can be available as the re-usable
components with lot of flexibility
|
|
In MVC
architecture Servlet acts as controller.
|
In MVC
architecture JSP acts as view.
|
|
Servlet advantages include:
· Performance: get
loaded upon first request and remains in memory indefinitely.
· Simplicity: Run
inside controlled server environment.
· Session Management :
overcomes HTTP's stateless nature
· Java Technology : network access,
Database connectivity, j2ee integration
|
JSP Provides an extensive infrastructure for:
·
Tracking
sessions.
·
Managing
cookies.
·
JSP is Extensible: Can create custom tags to extend the
JSP functionality.
·
Separation of roles: Clearly identifies separation of
roles for Developers, Content Authors/ Graphic Designers/ Web Masters.
|
So if we need to return a view in case of servlet's , the only way is to create an html page in java with quotes and all,and then send them in response??? Correct??
ReplyDeleteCorrect :)
DeleteSo if we need to return a view in case of servlet's , the only way is to create an html page in java with quotes and all,and then send them in response??? Correct??
ReplyDeleteSuper Jasdhir sir
ReplyDeleteIn servlets view is an html page but in jsp view is jsp page onley. Is it correct?
ReplyDeleteThis is a great post thhanks
ReplyDelete