-
What is the query used to display
all tables names in SQL Server
(Query analyzer)?
select * from information_schema.tables
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How many types of JDBC Drivers
are present and what are they?-
There are 4 types of JDBC Drivers
-
Can we implement an interface in
a JSP?- No
-
What is the difference between
ServletContext and PageContext?-
ServletContext: Gives the
information about the container.
PageContext: Gives the information
about the Request
-
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.
-
How to pass information from JSP
to included JSP?- Using <%jsp:param>
tag.
-
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.
-
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.
-
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.
-
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);
-
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.
-
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().
-
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.
-
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.
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).
-
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+)
-
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.