Gateway for Preparing Interviews
What do you understand by client side and server side templating The modern Rich Internet Applications (RIA) use the design concept of “single page web design”, where a single rich page makes ajax based service calls to render different sections of a page instead of the traditional approach of loading a new page of each user action.The “single page web design” … Read more
Explain different ways of creating a thread Threads can be used by either: Extending the Thread class. Implementing the Runnable interface. Using the Executor framework (this creates a thread pool) By extends: class Counter extends Thread { //method where the thread execution will start public void run(){ //logic to execute in a thread } //let’s see how to start the … Read more
What types of comments are available in the JSP? There are two types of comments that are allowed in the JSP. They are hidden and output comments. A hidden comment does not appear in the generated HTML output, while output comments appear in the generated output. Example of hidden comment: < % – – This … Read more
In the Servlet 2.4 specification SingleThreadModel has been deprecated, why Because it is not practical to have such model. Whether you set isThreadSafe to true or false, you should take care of concurrent client requests to the JSP page by synchronizing access to any shared objects defined at the page level. Can you give some … Read more
Why is locking of a method or block of code for thread safety is called “synchronized” and not “lock” or “locked When a method or block of code is locked with the reserved “synchronized” key word in Java, the memory (i.e. heap) where the shared data is kept is synchronized. This means,When a synchronized block … Read more
How do you restrict page errors display in the JSP page You first set “Errorpage” attribute of PAGE directory to the name of the error page (ie Errorpage=”error.jsp”)in your jsp page .Then in the error jsp page set “isErrorpage=TRUE”. When an error occur in your jsp page it will automatically call the error page. How … Read more
What is JSP tag file A source file containing a reusable fragment of JSP code that is translated into a tag handler when a JSP page is translated into a servlet. What is JSP container A container that provides the same services as a servlet container and an engine that interprets and processes JSP pages … Read more
What is the difference between sleep(), suspend() and wait() Thread.sleep() takes the current thread to a “Not Runnable” state for specified amount of time. The thread holds the monitors it has acquired. For example, if a thread is running a synchronized block or method and sleep method is called then no other thread will be … Read more
How can I set a cookie and delete a cookie from within a JSP page Cookie mycook = new Cookie(“name”,”value”); response.addCookie(mycook); Cookie killmycook = new Cookie(“mycook”,”value”); killmycook.setMaxAge(0); killmycook.setPath(“/”); killmycook.addCookie(killmycook); What is JavaServer Pages Standard Tag Library (JSTL A tag library that encapsulates core functionality common to many JSP applications.JSTL has support for common, structural tasks … Read more
When init() and Distroy() will be called init() is called whenever the servlet is loaded for the first time into the webserver.it performs certain one time activities which are required during the lifetime of the servlet.It may be some initialisation of variables or a database connection. Destroy will be called whenever the servlet is removed … Read more