Shadab Khan

i've recently started experementing with ide's/editor....i used JBuilder for a while..its pretty decent..but i found it to be a little slow at times(or is it my machine?? )...i switched to eclipse 2 weeks back and so far iam loving it!! and what's more its free!!..i have started recommending it to collegues/friends and everyone seems to be loving it too

Hi
i have some confusion regarding how connection pooling is implemented..i have been doing some digging in to this lately but the more i read the more confused i get. i have some doubts here, will any of the posters here kindly clear them
a. Do i have to connect to my database via the DataSource method to take advantage of the connection pooling provided by my app server?..i have read conflicting information about this suggesting that Connection Pooling will not be provided to my app if i use DriverManager.getConnection()
b. if i chose to use the DataSource method do i have to implement the ConnectionPoolDataSource interface to provide the connection pooling for my app?
c. what is the best way to implement my own custom Connection pool?
Thanx

Hi
iam trying to oracle 8i through a simple JDBC program.iam able to connect to the db using the thindriver but when i try to connect it through OCI iam getting the following exception
Exception in thread "main" java.lang.UnsatisfiedLinkError: no ocijdbc8 in java.library.path at java.lang.Throwable.fillInStackTrace(Native Method) at java.lang.Throwable.fillInStackTrace(Compiled Code) at java.lang.Throwable.<init>(Compiled Code) at java.lang.Error.<init>(Error.java:50) at java.lang.LinkageError.<init>(LinkageError.java:43) at java.lang.UnsatisfiedLinkError.<init>(UnsatisfiedLinkError.java:42) at java.lang.ClassLoader.loadLibrary(Compiled Code) at java.lang.Runtime.loadLibrary0(Runtime.java:470) at java.lang.System.loadLibrary(System.java:778) at oracle.jdbc.oci8.OCIDBAccess.logon(OCIDBAccess.java:233) at oracle.jdbc.driver.OracleConnection.<init>(OracleConnection.java:269) at oracle.jdbc.driver.OracleDriver.getConnectionInstance(Compiled Code) at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:266) at java.sql.DriverManager.getConnection(Compiled Code) at java.sql.DriverManager.getConnection(DriverManager.java:137) at JdbcTest.main(Compiled Code)

Most likely questions you are going to get are :

Servlets and JSP
difference between servlet and a jsp?/..when to use one over another??
MVC Architecture, difference between model 1 and model 2??
life cycle of a servlet and a jsp?
difference between include tag and include directive?/
difference between forward and redirect??

what are the different ways of session handling ??..which is the preferred one?? and why??
different scopes in JSP?
Weblogic
how do you deploy a web application in weblogic?/..the directory structure etc
difference between managed server and adminstered server in weblogic?
ejb
why ejb??
difference between session bean and entity bean??
difference between stateful and stateless session bean??
difference between container managed and beanmanaged persistence??
what's new in ejb 2.0?

expect some questions on databases and JDBC
and be quite thorough with the projects that you've put you on ur resume..bulk of the questions will revolve around this.
Best of Luck

Most likely questions you are going to get are :
Servlets and JSP
difference between servlet and a jsp?/..when to use one over another??
MVC Architecture, difference between model 1 and model 2??
life cycle of a servlet and a jsp?
difference between include tag and include directive?/
difference between forward and redirect??

what are the different ways of session handling ??..which is the preferred one?? and why??
different scopes in JSP?
Weblogic
how do you deploy a web application in weblogic?/..the directory structure etc
difference between managed server and adminstered server in weblogic?
ejb
why ejb??
difference between session bean and entity bean??
difference between stateful and stateless session bean??
difference between container managed and beanmanaged persistence??
what's new in ejb 2.0?

expect some questions on databases and JDBC
and be quite through with the projects that you've put you on ur resume..bulk of the questions will revolve around this.
Best of Luck

yea..chris is right..you've gotta put your bean in the session..only then you can retrieve the set values
something like this will work
//NameServlet.java
NameBean bean=new NameBean();
bean.setName("satish");
HttpSession session=request.getSession(true);
session.setAttribute("mybean",bean);
ServletContext context=getServletContext();
RequestDispatcher rd;
rd=context.getRequestDispatcher("/Name.jsp");
rd.forward(req,res);
And in Name.jsp
<jsp:useBean id="mybean" scope="session" class="Bean.NameBean"/>
<%!mybean=(Bean.NameBean)session.getAttribute("mybean");%>
<%=mybean.getName()%>

Originally posted by Dale DeMott:

Actually if you could expand on this, I'd love to hear more about this question...
[ May 02, 2003: Message edited by: Dale DeMott ]

ok let me try again .. GenericServlet implements a servlet regardless of the protocol..its meant for servlets that are not neccessarily meant for the HTTP protocol..it provides a simple implementation of all the servlet lifecycle methods and it also has a service method in place but it takes the more "generic" ServletRequest and ServletReponse objects as parameters. i guess GenericServlet is probably in place because people back at Sun felt that in the near foreseeable future there might come a time when servlets might be run on protocols other than HTTP, at that time it will be easy to implement servlets for those particular portocols by extending the GenericServlet, so you probably will have one servlet class (like HttpServlet is for HTTP) for each of those protocols..ofcourse, right now servlets run only on the HTTP protocol..so you subclass from the HTTPServlet to implement a HTTP specific servlet

101. Why there are some null interface in java ? What does it mean ? Give me some null interfaces in JAVA ?
Null interfaces act as markers..they just tell the compiler that the objects of this class need to be treated differently..some marker interfaces are : Serializable, Remote, Cloneable

93. What is meant by Servlet? What are the parameters of the service method ?
A Servlet is a java class that extends the request-response model of an webserver. it recieves request from a client performs any neccessary operations..builds a response object and sends it back to the client.
The Parameteres of the service method are HttpServletRequest and HttpServletResponse objects

public void service(HttpServletRequest request, HttpServletResponse response)
114. What is meant by cookies ? Explain ?
A Cookie is a small bit of textual information send by an website to the browser with some information about the user. The browser sends it back to the webserver upon subsequent visits of the user to that particular website.
96. What is the difference in between the HTTPServlet and Generic Servlet ? Explain
A GenericServlet is a protocol independent servlet. The HttpServlet class extends the GenericServlet..it is meant specifically for the HTTP protocol

Hi
how do i make sure that only one object of my class is loaded in to memory at any given time??

This site has a pretty decent ejb mock test..check it out.
http://www.stormpages.com/jnagal/

hi
i was this question by an interviewer today..my answer was the compiler wont allow it..and then i went to lengths explaining him the concept of abstract classes and how they implemented in derived class and only then you can have objects of that type..but still he kept asking me why??..give me a particular reason!!..is there any particular answer to it??

109. Latest version of JDBC and new features.
The latest version of JDBC is JDBC 3.0 . Some of the new features that are included in it are :
Support for SavePoints
Improved Support CLOB and BLOB data types
Ability to open multiple Resultsets
Addition of Boolean Data type
Retrieval of auto-generated keys
i'll try to answer more questions when i get time..iam preparing for an interview myself

BTW Debashish Excellent job..it's posters like you that make this forum worth visiting

iam definitely interested...count me in too

ok kiddo.. found a weblogic 5 properties file hiding somewhere in the dark corners of my hard disk..so let me make this a bit more easier for you..iam pasting the JSP section from this file
# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
# WEBLOGIC JSP PROPERTIES
# ------------------------------------------------
# Sets up automatic page compilation for JSP. Adjust init args for
# directory locations and uncomment to use.
#weblogic.httpd.register.*.jsp=\
# weblogic.servlet.JSPServlet
#weblogic.httpd.initArgs.*.jsp=\
#pageCheckSeconds=1,\
#compileCommand=f:/jdk1.2/bin/javac.exe,\ #workingDir=g:/weblogic/myserver/classfiles,\
#verbose=true
locate this section in ur weblogic.properties file..remove those # marks at the beggining of each line...change the properties called "compileCommand" and "workingdir" according to ur local settings.
compileCommand -> the path to ur java compiler and
workingdir ->the path to the working directory which weblogic uses to store servlets generated after compiling jsps
save the file and restart the server.

its been a long time since i worked on weblogic 5..but let me try..
locate the Section titled "Weblogic JSP properties" in the weblogic.properites...uncomment the lines in this secion..this sets up the dynamic page compilation for .jsp page...This should do the trick
[ February 13, 2003: Message edited by: Troy Smith ]