Java Quiz Program Using Database Based Serv Lets
Servlets is a very important topic of Java EE and all of the web applications frameworks such as Spring and Struts is built on top of it. This makes servlet interview questions a hot topic in interviews. Here I am providing a list of 50 servlet interview questions with answers to help you tackle most of the interview questions related to servlets and web applications in java.
java quiz program using database based serv lets
Ans: The Packages are used to separate the servlets under a directory to eradicate confusion among programmers working simultaneously on creating servlets on the same server. This can be done through the following steps:
I have created a web system using Java Servlets and now want to make JUnit testing. My dataManager is just a basic piece of code that submits it to the database. How would you test a Servlet with JUnit?
Servlets are the Java programs that run on the Java-enabled web server or application server. They are used to handle the request obtained from the webserver, process the request, produce the response, then send a response back to the webserver.
CGI is actually an external application that is written by using any of the programming languages like C or C++ and this is responsible for processing client requests and generating dynamic content. In CGI application, when a client makes a request to access dynamic Web pages, the Web server performs the following operations :
Following quiz provides Multiple Choice Questions (MCQs) related to Servlets Framework. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.
A servlet is a small Java program that runs within a Web server. Servlets receive and respond to requests from Web clients, usually across HTTP, the HyperText Transfer Protocol. Servlets can also access a library of HTTP-specific calls and receive all the benefits of the mature Java language, including portability, performance, reusability, and crash protection. Servlets are often used to provide rich interaction functionality within the browser for users (clicking link, form submission, etc.)
Servlets have a variety of ways to realize access to information. For the bulk of it, every method returns a specific result. Compared with CGI programs its information by making use of passed environment variables, One can see multiple advantages by using the servlet approach.
It is standard to have a single servlet instance for each registered name of the servlet. However, instead of this, it is also possible for a servlet to choose to have a pool of instances created for each of its names that all share the task of handling requests. These servlets indicate this action by implementing the javax.servlet.SingleThreadModel interface.
The core of the Servlet API is the javax.servlet package. It includes the basic Servlet interface, which all servlets must implement in one form or another, and an abstract GenericServlet class for developing basic servlets.
Unlike CGI and FastCGI, which use many processes to handle separate programs and separate requests, servlets are all handled by separate threads within the webserver process. Thus, the servlets are efficient and scalable. As servlets run within the web server, they can interact very closely with the server to do things that are not possible with CGI scripts.
Java Servlet technology and JavaServer Pages (JSP pages) are server-side technologies that have dominated the server-side Java technology market; they've become the standard way to develop commercial web applications. Java developers love these technologies for myriad reasons, including: the technologies are fairly easy to learn, and they bring the Write Once, Run Anywhere paradigm to web applications. More importantly, if used effectively by following best practices, servlets and JSP pages help separate presentation from content. Best practices are proven approaches for developing quality, reusable, and easily maintainable servlet- and JSP-based web applications. For instance, embedded Java code (scriptlets) in sections of HTML documents can result in complex applications that are not efficient, and difficult to reuse, enhance, and maintain. Best practices can change all that.
Similar to Common Gateway Interface (CGI) scripts, 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. Unlike CGI scripts, however, servlets run within the same process as the HTTP server.
In the simplest terms, then, servlets are Java classes that can generate dynamic HTML content using print statements. What is important to note about servlets, however, is that they run in a container, and the APIs provide session and object life-cycle management. Consequently, when you use servlets, you gain all the benefits from the Java platform, which include the sandbox (security), database access API via JDBC, and cross-platform portability of servlets.
Servlet technology is robust and scalable because of java language. Before Servlet, CGI (Common Gateway Interface) scripting language was common as a server-side programming language. However, there were many disadvantages to this technology. We have discussed these disadvantages below.
With Java EE annotations, the standard application.xml and web.xml deployment descriptors are optional. The Java EE programming model uses the JDK 6.0 annotations feature for Web containers, such as EJBs, servlets, Web applications, and JSPs. See WebLogic Annotation for Web Components and For more information about Java EE Web application technologies, see -138511.html.
JSPs and HTTP servlets can access all services and APIs available in WebLogic Server. These services include EJBs, database connections by way of Java Database Connectivity (JDBC), Java Messaging Service (JMS), XML, and more.
A servlet is a Java class that runs in a Java-enabled server. An HTTP servlet is a special type of servlet that handles an HTTP request and provides an HTTP response, usually in the form of an HTML page. The most common use of WebLogic HTTP servlets is to create interactive applications using standard Web browsers for the client-side presentation while WebLogic Server handles the business logic as a server-side process. WebLogic HTTP servlets can access databases, Enterprise JavaBeans, messaging APIs, HTTP sessions, and other facilities of WebLogic Server.
JSPs are Web pages coded with an extended HTML that makes it possible to embed Java code in a Web page. JSPs can call custom Java classes, called taglibs, using HTML-like tags. The WebLogic appc compiler weblogic.appc generates JSPs and validates descriptors. You can also precompile JSPs into the WEB-INF/classes/ directory or as a JAR file under WEB-INF/lib/ and package the servlet class in the Web archive to avoid compiling in the server. Servlets and JSPs may require additional helper classes to be deployed with the Web application.
Servlets are mostly used because they are platform-independent Java classes and are compiled to platform-neutral byte code. Java byte code can be loaded dynamically into and run by java enabled web server.
A servlet container is a part of Web server that provides network services depends on request and response are sent, MIME based requests and responses. It contains and manages servlets through their life cycle.@media(max-width: 1023px) .videocontentmobile min-height: 250px; @media(min-width: 1024px) .videocontentmobile min-height: 250px !important; if (typeof(pubwise) != 'undefined' && pubwise.enabled === true) pubwise.que.push(function() pubwise.renderAd('div-gpt-ad-9431967-3'); ); else googletag.cmd.push(function () googletag.display('div-gpt-ad-9431967-3'); googletag.pubads().refresh([gptadslots['div-gpt-ad-9431967-3']]); );
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