Servlets Interview Questions and Answers

Ques 6. Given the request path below, which are context path, servlet path and path info?

Ans. /bookstore/education/index.html

context path: /bookstore
servlet path: /education
path info: /index.html

Ques 7. What is filter? Can filter be used as request or response?

Ans. A filter is a reusable piece of code that can transform the content of HTTP requests,responses, and header information. Filters do not generally create a response or respond to a request as servlets do, rather they modify or adapt the requests for a resource, and modify or adapt responses from a resource.

Ques 8. When using servlets to build the HTML, you build a DOCTYPE line, why do you do that?

Ans.

Ques 9. What is new in ServletRequest interface ? (Servlet 2.4)

Ans. The following methods have been added to ServletRequest 2.4 version:
public int getRemotePort()
public java.lang.String getLocalName()
public java.lang.String getLocalAddr()
public int getLocalPort()

Ques 10. Request parameter How to find whether a parameter exists in the request object?

Ans. 1.boolean hasFoo = !(request.getParameter("foo") == null || request.getParameter("foo").equals(""));
2. boolean hasParameter = request.getParameterMap().contains(theParameter);
(which works in Servlet 2.3+)