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1.What is the query used to display all
tables names in SQL Server (Query
analyzer)?
Ans: select * from
information_schema.tables
2.How many types of JDBC Drivers are
present and what are they?- Ans:There
are 4 types of JDBC Drivers
JDBC-ODBC Bridge Driver
Native API Partly Java Driver
Network protocol Driver
JDBC Net pure Java Driver
3.Can we implement an interface in a JSP?-
No
4.What is the difference between
ServletContext and PageContext?-
Ans:ServletContext: Gives the
information about the container.
PageContext: Gives the information about
the Request
5.What is the difference in using
request.getRequestDispatcher() and
context.getRequestDispatcher()?-
request.getRequestDispatcher(path): In
order to create it we need to give the
relative path of the resource,
context.getRequestDispatcher(path): In
order to create it we need to give the
absolute path of the resource.
6.How to pass information from JSP to
included JSP?- Using <%jsp:param> tag.
7.What is the difference between
directive include and jsp include?- <%@
include>: Used to include static
resources during translation time. JSP
include: Used to include dynamic content
or static content during runtime.
8.What is the difference between
RequestDispatcher and sendRedirect?-
RequestDispatcher: server-side redirect
with request and response objects.
sendRedirect : Client-side redirect with
new request and response objects.
9.How does JSP handle runtime
exceptions?- Using errorPage attribute
of page directive and also we need to
specify isErrorPage=true if the current
page is intended to URL redirecting of a
JSP.
10.How do you delete a Cookie within a
JSP?
Cookie mycook = new
Cookie(\"name\",\"value\");
response.addCookie(mycook);
Cookie killmycook = new Cookie(\"mycook\",\"value\");
killmycook.setMaxAge(0);
killmycook.setPath(\"/\");
killmycook.addCookie(killmycook);
11.How do I mix JSP and SSI #include?-
If you’re just including raw HTML, use
the #include directive as usual inside
your .jsp file.
<!--#include file="data.inc"-->
But it’s a little trickier if you want
the server to evaluate any JSP code
that’s inside the included file. If your
data.inc file contains jsp code you will
have to use
<%@ vinclude="data.inc" %>
The <!–#include file="data.inc"–> is
used for including non-JSP files.
12.I made my class Cloneable but I still
get Can’t access protected method clone.
Why?- Some of the Java books imply that
all you have to do in order to have your
class support clone() is implement the
Cloneable interface. Not so. Perhaps
that was the intent at some point, but
that’s not the way it works currently.
As it stands, you have to implement your
own public clone() method, even if it
doesn’t do anything special and just
calls super.clone().
13.Why is XML such an important
development?- It removes two constraints
which were holding back Web
developments: dependence on a single,
inflexible document type (HTML) which
was being much abused for tasks it was
never designed for; the complexity of
full SGML, whose syntax allows many
powerful but hard-to-program options.
XML allows the flexible development of
user-defined document types. It provides
a robust, non-proprietary, persistent,
and verifiable file format for the
storage and transmission of text and
data both on and off the Web; and it
removes the more complex options of
SGML, making it easier to program for.
14.What is the fastest type of JDBC
driver?- JDBC driver performance will
depend on a number of issues:
the quality of the driver code,
the size of the driver code,
the database server and its load,
network topology,
the number of times your request is
translated to a different API.
15.In general, all things being equal,
you can assume that the more your
request and response change hands, the
slower it will be. This means that Type
1 and Type 3 drivers will be slower than
Type 2 drivers (the database calls are
make at least three translations versus
two), and Type 4 drivers are the fastest
(only one translation).
16.How do I find whether a parameter
exists in the request object?
boolean hasFoo = !(request.getParameter(\"foo\")
== null
|| request.getParameter(\"foo\").equals(\"\"));
or
boolean hasParameter =
request.getParameterMap().contains(theParameter);
//(which works in Servlet 2.3+)
17.How can I send user authentication
information while makingURLConnection?-
You’ll want to use
HttpURLConnection.setRequestProperty and
set all the appropriate headers to HTTP
authorization. |