0
JSP and Servlets
JSP (JavaServer Pages) are Java programs encoded within webpages that research and generate pertinent results. Servlets, on the other hand, are objects (programs) that handle requests from users and provide results based on these requests.
261 Questions
JavaServer Pages (JSP) is a Java technology that helps software developers serve dynamically generated web pages based on HTML, XML.
How you convert int to string in jsp?
The same way you would in a regular java program.
int i = 10;
String s = i + "";
after the above line of code the variable s will have "10" as a string value...
People who are suspected of having an intestinal blockage or who suffer from narrowing of the esophagus or any other part of the intestinal tract should not use psyllium.
How do you give connection between HTML and java servlet?
You cannot. HTML is a static file and it cannot interact with a Java Servlet. A Servlet can always redirect to a HTML page but the other way round cannot happen.
The OLAP allows Nabisco to accurately track sales and consumer preferences
With the Eyeball Method, the dieter's hand is used to judge portion sizes. For low fat proteins (chicken and fish), the portion should be approximately the size and thickness of the dieter's palm.
A servlet is nothing but Java code that runs in a container. It generates HTML & other contents that get displayed in the web page that we see. It is purely coded in Java, so the benefits and restrictions of all regular Java classes apply here too. Servlets are compiled to form a platform neutral bytecode (All java code is platform neutral, isnt it? Serlvet is no different). Upon request, this bytecode file is loaded into a container. Some containers (servlet engines) are integrated with the Web server, while others are plug-ins or extensions to Web servers that run inside the JVM. Servlets look the same as static Web pages to the client, but they really are complete programs capable of complex operations.
Why do you use superclass init method inside your init method in a servlet?
Because, that is how all Java classes work. When a class is initialized/created all the classes it extends from (its super classes) need to be initialized as well.
Is it mandatory to learn servlets before JSP?
No. But, knowledge of Servlets would be an added advantage if you are learning JSPs
Difference between HTTP servlet and Generic servlet?
The difference is that a GenericServlet has no defined protocol (it is "generic"), while HttpServler uses the HTTP protocol. HttpServlet is a subclass of GenericServlet with the purpose of creating a servlet for a web site.
In any JSP Page, there are a bunch of implicit objects that are available for the programmer to use. It contains a variety of information that can be used to display stuff on the page. The following JSP Implicit Objects are available for a programmer:
• request
• response
• out
• session
• config
• application
• page
• pageContext
What is servlet and why it is used?
servlet is a small program which run on serverside,and it can not be downloaded at client side.
java servlets dynamically extends the functionalities of a web server.
main use is:
session tracking: no of users (unique) visited u'r website.
in order to use cookies..
What are the components of jsp?
A JSP File Contents:
A JSP file can contain the following:
a. HTML contents
b. JavaScript
c. Java Code
Combining the features of the above 3 mentioned items; we get a powerful entity called the JSP. JSPs are used for the User Interface layer or the more colloquially called Front End layer of any J2EE application.
JSP Skeleton
Below is how a Skeleton JSP File would look like. (The file has to be saved as .jsp)
// Page Imports
<%@ page import = "com.xyz.ClassName %>
// Tag Library References
<%@ taglib URI = "path to Taglib file" prefix = "xx" %>
// here xx refers to the prefix with which the tag library will be referred to
// HTML Head & Title Content
// Java Script Content
// HTML Body & Form Contents
Note: Java code can be placed within the <% %> tags in the body part of the JSP page within the Body tags.
As you can see, a JSP file is pretty straightforward. Also, an important point to note here is the fact that, not all of the entities mentioned above are mandatory. You can include or exclude any of the entities mentioned above, based on your requirement and convenience.
JSP is used for the V part of the MVC Architecture.
MVC stands for Model-View-Controller Architecture and JSPs are used for the views.
You can refresh the web page by the thing below.
- By clicking the F5 function key or
- By clicking on the Refresh symbol in the Web Browsers task bar ( The one with two arrows pointing at one another in a circle. )
What is the difference between JSP and JSPX?
http://diaryproducts.net/about/programming_languages/java/convert_jsp_pages_to_jsp_documents_jspx_with_jsp2x
What is the difference between networking and servlet in java?
Networking is a basic action. A servlet in Java is a single part of networking, a single task.
JSP stands for Java Server Pages.
Java Server Pages have become an integral part of any J2EE application. They are used extensively because they can combine the features of HTML and Java. The difficulty level of JSP is half-way between HTML and pure Java. For simple tasks like displaying the current date, you write a normal HTML page and add only a small amount of Java as a scriptlet. For big tasks like processing a shopping cart, you use JSP as the mediator between the Web form and a component (Ex: Servlet) that has all the processing logic.
CGI, Perl, Active Server Pages etc were all the predecessors of Java Server Pages. Am not saying that the JSP Technology was built based on these technologies but it is safe to say that, the JSP Technology was created to overcome many of the shortcomings in the above mentioned technologies. Though the ASP technology is a web server scripting champion and is used very widely, the only problem is the Runs only in Windows Attitude of the technology. Unlike ASP, JSP has equivalent if not better features and can run in any environment making it an invaluable tool for enterprise application developers who don't want to be tied to the limitation of the system running only in Windows.
Not only does JSP run on all major platforms, but the JavaBeans used by these JSPs run on all major platforms as well.
JSP competes directly with ASP. In fact, you would be forgiven if you thought it was a copy. Sun took the same approach to JSP as it did with Java. Sun borrowed the syntax of its best competitor (ASP for JSP and C++ for Java) tweaked it a little, but built everything under the hood from scratch. Java syntax comes from C++, but it works on all platforms with no portability issues like C++ for the developer. Similarly, the JSP structure comes from ASP. The look and feel, and even some syntax is the same. However, ASP primarily uses Microsoft's versatile VBScript, while JSP uses the more powerful and portable Java and JavaScript.
doPost() is the method in the servlet that is used to service the Http requests submitted using the Post option.
HTML forms can be submitted in two ways using the Get method and the Post method. You can specify the method while declaring the form itself. So you will have two methods in the servlet doGet() and doPost() each for one of them
What is doGet method in servlet?
The doGet() method is the method inside a servlet that gets called every time a request from a jsp page is submitted. The control first reaches the doGet() method of the servlet and then the servlet decides what functionality to invoke based on the submit request. The get method called when the type of page submission is "GET"
There is another way of submitting requests from a jsp page is "POST" and when that happens it calls the doPost() method inside the servlet.
What is the difference between ASP and JSP?
ASP stands for "Active Server Pages"
JSP stands for "Java Server Pages"
asp(classic) is interpreted, which means the code has to be read each time a page is called. jsp is compiled into java classes which makes for a much faster page generation.
Classic asp(not the new .NET) has to rely on Active X, COM or other Microsoft technologies to really enhance functionality of the code. jsp can bring in every java capability.
Handling email in asprequires external components such as CDONTS or aspMail and was tricky to implement. JavaMail for jsp was a 10 minute download and was much easier to use.
