| XMLEncoder & DefaultPersistenceDelegate |
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Index ‹ java-programmer
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- 2
- External process output missingHello,
I'm using Runtime.getRuntime().exec(procedureFile) to run external
system commands stored in procedure files, and I get their output from
process.getInputStream().
This works OK in Windows, but when I try it in a Unix system I get the
direct output (i.e. procedure echos) but not the output from the
programs run by the procedure. For example:
#!/bin/sh
PATH=/bin:/usr/bin:/usr/local/bin:/usr/local/sysadm/bin:
export PATH
echo "Starting remote copy for $1"
scp -r $1 map@remotehost:/apps/myapp
echo "End of remote copy for $1"
would return the two echo messages, but not the output from scp.
Is there something that must be done or declared to get all the output
in Unix?
Thanks for any hint,
Guifre
- 2
- Announcing License Manager 2.25 for JavaLicense Manager allows you to license and protect your java code.
Create eval/temprorary licenses, enable and disable software features,
node locking.
For more information see
http://www.elevenprospect.com
Version 2.25 provides the following new features:
-JDK 1.5 support
-Ability to create licenses independent of jar files.
License Manager Team.
- 2
- Discussion on technologies-Bangalore & Chennai, IndiaHi!
A leading MNC is organising an informal event in Bangalore, India (Oct
6, 4 to 5 PM) and Chennai, India (Oct 14/15 - Tentative) to discuss
different aspects of a technology and its use in business.
The objective of the discussion is to
1. Understand the views of techies on various technologies and
platforms (Java, Linux, Unix, Microsoft etc)
2. Perception and image of each of the platforms/technologies
3. Utility of the engagement efforts taken up by the companies in the
form of events, communities etc..,
The duration would be 1 hour. You may participate in either Bang. or
Chennai.
To register send the following info to email***@***.com:
1. Profession:
2. Company name (may skip this if confidential):
3. Contact Number:
4. Location:
5. Technology working on:
6. IT Work experience (months, if applicable):
Participants, don't forget to collect goodies :)
- 3
- Beanshell self-reference causes memory leakDear All,
I have come across a phenomena in Beanshell, which I am pretty sure is
a bug. I have put together a very simple test. I wanted to know if
anyone has already come across this, before I submit a bug report.
I have included below the source for a very simple test which can be
run from the command line. Although the test prints out memory usage,
the phenomena is best observed using a memory tool such a JProfiler.
Unfortunately, I can't attach here a screen-shot from JProfiler to
graphically illustrate the problem.
The core issue is this:
If I setup a self-referencing circle with the Interpreter like so (in
standard Java code):
{
this.interpreter = new bsh.Interpreter();
this.interpreter.set( "ref", this );
}
It sets up objects in the JVM memory which can never ever be garbage
collected, even though there is no reference them, and the "this"
object is out of scope in the calling method.
This is in contrast to, say a HashSet:
{
this.set = new HashSet();
onethis.set.add( this );
}
This setup does appear to garbage collect when the "this" object goes
out of scope.
The code for Test.java is below. Its output follows. Note that after
the self-referencing setup, roughly 90Kb has not been garbage
collected, compared with 20Kb for the HashSet and 200 bytes for two
java objects.
Before tests
------------
10528
40
------------
Waiting ...
After object ref test
---------------------
26944
208
---------------------
Waiting ...
After HashSet test
------------------
158280
22760
------------------
Waiting ...
After Interpreter test
----------------------
362648
91352
----------------------
Waiting ...
If this test is run with JProfiler, it can be seen that both the
self-referencing Test objects, and the self-referencing HashSet setup
are successfully garbage collected.
But JProfiler shows the Interpreter still in memory after the object of
class Test has gone out of scope - at the very final part of the
program.
The Interpreter is not garbage collected.
Obviously, if you do this enough in an application, it will cripple it
for speed and eventually bomb out with an "Out of heap space" error.
Any thoughts?
Regards,
Stewart
import java.io.*;
import java.util.*;
import bsh.*;
public class Test
{
private static Runtime r = Runtime.getRuntime();
private static long baseline = 0L;
public static void main(String[] args)
throws Exception
{
System.gc();
baseline = (r.maxMemory() - r.freeMemory());
report("Before tests");
twoObjectTest();
report("After object ref test");
hashSetTest();
report("After HashSet test");
interpreterTest();
report("After Interpreter test");
}
private Test ref = null;
private HashSet<Test> s = null;
private Interpreter i = null;
private static void twoObjectTest()
{
Test one = new Test();
Test two = new Test();
one.ref = two;
two.ref = one;
}
private static void hashSetTest()
{
Test one = new Test();
one.s = new HashSet<Test>();
one.s.add( one );
}
private static void interpreterTest()
throws EvalError
{
Test one = new Test();
one.i = new Interpreter();
one.i.set( "ref", one );
}
private static void report(String string)
throws IOException
{
char[] lines = new char[string.length()];
Arrays.fill(lines, '-');
System.out.println( );
System.out.println( string );
System.out.println( lines );
System.out.println( (r.maxMemory() - r.freeMemory() - baseline) );
System.gc();
System.out.println( (r.maxMemory() - r.freeMemory() - baseline) );
System.out.println( lines );
System.out.println("Waiting ...");
new BufferedReader( new InputStreamReader( System.in )).readLine();
}
/**
* I thought this might solve the problem, but of course, it never
gets called.
*/
protected void finalize()
throws Throwable
{
i.set( "ref", null );
i.unset( "ref" );
i = null;
}
}
- 3
- Bug#285014: java-common; correction for README.Debian-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Package: java-common
Version: 0.222
Severity: minor
In the file /usr/share/doc/common-java/README.Debian, the following lines:
They can be found at
/usr/share/doc/java-common/debian-java-faq.html
and
/usr/share/doc/java-common/debian-java-policy.html
should probably read:
They can be found at
/usr/share/doc/java-common/debian-java-faq/index.html
and
/usr/share/doc/java-common/debian-java-policy/index.html
Thanks,
- --
Barry Hawkins
All Things Computed
site: www.alltc.com
weblog: www.yepthatsme.com
Registered Linux User #368650
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.5 (GNU/Linux)
iD8DBQFBuRhC7bZ6kUftWZwRAtOTAKDMHWW9jUWEaqVC/qZHq+Cq/T+ohwCfeqHZ
nSqMQ2c9L16CzGJOOw+FoMo=
=0S/K
-----END PGP SIGNATURE-----
--
To UNSUBSCRIBE, email to email***@***.com
with a subject of "unsubscribe". Trouble? Contact email***@***.com
- 3
- Using Apache Derby in Tomcat applicationHeya,
I'm trying to integrate Derby as an embedded db into the Roller web log
app on Tomcat. All the FAQs and install instructions describe how to
1. create the jdbc/rollerdb JNDI resource and DataSource in the
server.xml file.
2. place the Derby JDBC driver in Tomcat's common/lib subdir
I have a couple problems with this:
1. I don't control the Tomcat installation and don't have access to the
common/lib directory. However, I do have access to a CATALINA_BASE dir
in my home directory and to the app's WEB-INF directory.
2. Without putting the driver in common/lib, the existing instructions
cause exceptions trying to find the Derby driver...obviously derby.jar
isn't in common/lib but is instead in my app's WEB-INF/lib directory.
3. Creating a global JNDI resource and DataSource in server.xml is
causing the exceptions in #2 above.
So, can anyone help me understand how to add the DataSource resource and
JNDI entry somewhere just local to the app itself. I'm trying to put
this information into WEB-INF/web.xml, but I'm not sure this is
possible. Any thoughts?
Thanks for your help!
Regards,
John O'Conner
- 3
- 9
- org.xml.sax.helper Event problemsTrying to use org.xml.sax parser, extended DefaultHandler to
handle my xml while parsing.
However, DefaultHandler.characters(...) were called twice while
parsing one text element. Seems two events were fired instead of one,
and this only happens occasionally.
Any idea what could have caused this behavior?
Sam Zhang
- 9
- My Girlfriend Naked 504Photos of my busty girlfriend naked
http://24.116.180.212:89/myhomeporn/Girlfriend.scr
ytclxvejwzpkbdxsjlj
- 11
- GUI over command line applicationHi there!
I have a command line application. It does something and prints texts on the
screen with Syste.out.println(). And now I want to make another program that
has a GUI and can start/stop this first one and can catch the text printed
on the screen and show it in the textarea. Can it by done? How?
Regards,
Marcin
- 12
- specifiy9ing new JVM options??Hi,
Can anyone point me to some resources on explaining specifying new JVM
options? For example, some java profilers have some jvm options like
-XRunprofilerDLL or -Xrunpri . How are these things handled?
I know the basics of proifiler implementing a profiler agent talking
to jvm through jvmpi. But I am not sure how they start themselves and
load the tobeprofiled app. And it seems we can also "attach"
themselves when the app is running provided the pid is known for the
target jvm. How is this working?
Thanks.
- 12
- JProgressBar... need assiatance pleaseI'm playing with the idea of showing a JProgressBar in a small App' I trying
to make.
I want to display the progress of an array being populated....however I cant
seem to get the bar to show the actual % state before it reaches 100%
Am I missing something out?
Please help me if you can..
Thanks...
#######################
CODE BELOW
#######################
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ArrayRandom extends JFrame {
protected final int size = 100000;
protected int[] prodRandm = new int[size];
protected int min = 0;
protected int max = 100;
protected JProgressBar progress;
protected JButton start;
public ArrayRandom() {
setSize(300,50);
progress = new JProgressBar();
progress.setStringPainted(false);
progress.setIndeterminate(true);
start = new JButton("Start");
ActionListener act = new ActionListener() {
public void actionPerformed(ActionEvent e) {
progress.setMinimum(min);
progress.setMaximum(max);
progress.setIndeterminate(false);
progress.setStringPainted(true);
for (int i = 0; i < size; i++) {
prodRandm[i] = i;
progress.setValue((i/1000)+1);
progress.setString((i/1000)+1+" %");
}
}
};
start.addActionListener(act);
getContentPane().setLayout(new BorderLayout(10,10));
getContentPane().add(progress, BorderLayout.CENTER);
getContentPane().add(start, BorderLayout.WEST);
}
public static void main(String[] args) {
ArrayRandom frame = new ArrayRandom();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
- 12
- history.back problem with firefoxHi,
I have 2 submit buttons in a jsp page. One of them takes me to
page2.jsp and also passes the values enetered to page2.I have a link
in the page2 that does a history.back to come to the previous page to
make any chnages necessary. Now after making my changes, instead of
going to page2.jsp if I want to submit the page, Instead of submitting
the page it takes me to page2.jsp again.
This problem is only with firefox. It works fine with IE. Can anyone
help me on this?
- 13
- TemplatePrinter copiesI am trying to get a template to print multiple copies of a page. I thought
it would be as simple as setting:
printer.copies = 10;
printer.collate = true;
printer.usePrinterCopyCollate = true;
This does not work. Do I have to program a for loop in the template to
print each copy or is IE supposed to be creating the multiple copies
(collated or not depending on the collate variable I set). The loop should
be easy enough, but I was expecting IE to take care of it for me.
Thanks,
David
- 16
- Really simple one...I've managed to download, install and compile a swing program for the Mac OS
9.2. Now I want to run it, but I don't know how! (I'm a non-mac user!). How
do you run it (its not a jar)!
|
| Author |
Message |
lasandell
|
 Posted: 2005-11-6 1:37:00 |
Top |
java-programmer, XMLEncoder & DefaultPersistenceDelegate
I am trying to encode EventObject's as XML using XMLEncoder. As
subclasses of EventObject/AWTEvent are generally NOT java beans (they
do not provide a nullary constructor), I have to provide an instance of
DefaultPersistenceDelegate which specifies which properties are set by
the constructor. I tried to this with ActionEvent as follows:
encoder.setPersistenceDelegate( ActionEvent.class, new
DefaultPersistenceDelegate(
new String[] {"source", "ID", "actionCommand", "modifiers",
"when"} )
);
Unfortunately, when I call encoder.writeObject with an argument of type
ActionEvent, I get the following exception:
java.lang.NoSuchMethodException: <unbound>=Class.new(null, Integer,
"1", Integer, Long);
Continuing ...
java.lang.Exception: XMLEncoder: discarding statement
XMLEncoder.writeObject(ActionEvent);
Continuing ...
It is apparently unable to find the constructor due to the first
argument being null. However, "source" in my ActionEvent happens to not
be null. "source" is a property from EventObject rather than
ActionEvent, and I think this may be part of the problem. I have read
another post that says XMLEncoder has problems with superclass
properties.
Anybody have any ideas?
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lasandell
|
| Posted: 2005-11-6 1:49:00 |
Top |
java-programmer >> XMLEncoder & DefaultPersistenceDelegate
Oh one thing I forgot to mention... "source" is a transient property. I
don't know if XMLEncoder pays attention to the "transient" keyword,
however.
|
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lasandell
|
| Posted: 2005-11-6 1:55:00 |
Top |
java-programmer >> XMLEncoder & DefaultPersistenceDelegate
OK this is was horrible case of overconfidence.... it turns out that
getSource() is indeed returning null. I'm not sure why though, the
ActionEvent was generated by a Swing button; it should have that as its
source!
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Index ‹ java-programmer |
- Next
- 1
- How do I open a device in non-blocking mode?I'm a little stuck. I have a Linux device (a character device, like a
serial port) called /dev/cm15a0. I can't use RXTXcomm as it doesn't
recognize the device (and I'm having trouble recompile RXTX). I need
to open the device in non-blocking mode and read and write bytes
to/from the device. Any pointers?
--
Linux Home Automation Neil Cherry email***@***.com
http://www.linuxha.com/ Main site
http://linuxha.blogspot.com/ My HA Blog
Author of: Linux Smart Homes For Dummies
- 2
- Configuring Tomcat to NOT use webapps directorycurrently my webapps directory is something like:
C:\java\netbeans3.5.1\tomcat406\webapps
This is where the Netbeans install put it. I want to move the
directory to something a little more convenient to work with like:
c:\webapps
All I can find in the Tomcat configuration file is:
<Host name="localhost" debug="0" appBase="webapps" unpackWARs="true">
but if I change appBase to anything like "c:\webapps" or "c:/webapps"
it doesn't work. Can anybody tell me how to move the appBase
directory outside of the Tomcat or Netbean directory?
Thanks in advance.
Dean
- 3
- Changing button colors in a loopHi all:
I am working on a task that should imitate an elevator. I have two vertical
rows of round buttons "Up" and "Down" When a circle is selected randomly by
the program, the circle becomes yellow and the elevator moves to that
button.
Here is what I did:
1. created a class Circle where I save buttons' parameters
2. saved Circle objects in an array
3. drew the buttons depending on their parameters
4. generated a random number, matched it with an array index and assigned
the object color to yellow.
Everything is fine except that I can't figure out how to change colors of my
buttons in a loop. Help would be greatly appreciated!
import javax.swing.*;
import java.awt.*;
import java.util.*;
public class Elevator3 extends JPanel
{
private int n = 40;
private int width = 200;
private int floors = 10;
private int interval = 1000;
private boolean selected = false;
private Circle[] buttons = new Circle[2*(floors-1)];
public Elevator3()
{
build();
JFrame frame = new JFrame("Elevator3");
setBackground(Color.WHITE);
setFont(new Font("SansSerif", Font.PLAIN, Math.round(n/3)));
frame.getContentPane().add(this);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(width, n*(floors+2) );
frame.setVisible(true);
}
public void build()
{
Random r = new Random();
int buttonPick;
int timeUntilNextButton = r.nextInt(interval);
for (int k =0; ; k++)
{
if (timeUntilNextButton-- ==0)
{
buttonPick = r.nextInt(2*(floors-1));
//populate my buttons array here - how??
timeUntilNextButton = r.nextInt(interval);
}
}
//adding "Down" buttons
for (int i=1, count=0; i < floors; i++, count++)
{
if (count == buttonPick)
selected = true;
else
selected = false;
buttons[count]= new Circle(n*2, n*i, selected, Math.round(n/2));
}
//build an array of "Up" circles
for (int i=2, count=floors-1; i < floors+1; i++, count++)
{
if (count == buttonPick)
selected = true;
else
selected = false;
buttons[count]= new Circle(n, n*i, selected, Math.round(n/2));
}
}
public static void main(String[] args)
{
new Elevator3();
}
protected void paintComponent(Graphics g)
{
super.paintComponent(g);
//draw buttons
for (int i=0; i < buttons.length; i++)
{
g.setColor(buttons[i].getColor());
g.fillOval(buttons[i].getX(), buttons[i].getY(),
buttons[i].getWidth(), buttons[i].getWidth());
}
}
}
class Circle
{
private int x;
private int y;
private Color c;
private boolean pressed;
private int width;
public Circle(int xCoordinate, int yCoordinate, boolean selected,
int diameter)
{
x = xCoordinate;
y = yCoordinate;
pressed = selected;
width = diameter;
if (pressed)
c = Color.YELLOW;
else
c = Color.LIGHT_GRAY;
}
public Color getColor()
{
return c;
}
public int getX()
{
return x;
}
public int getY()
{
return y;
}
public int getWidth()
{
return width;
}
}
- 4
- class not found within IEHi,
I've written an applet. It properly works with Mozila. But with
Internet Explorer it says "Class [the applet's name] not found" or
something.
What is the problem? How can I fix it?
Thank you,
Siamak
- 5
- File upload with JSF.....Hi,
i'm a new user of java. I have a question. I have to develop a JSF
application that make user able to:
1) Upload a txt file
2) Showing to user columns and rows numbers of file.
For this second operation i'have developed a java application that
receive a txt file from a BufferedReader and counts rows and columns
number.
My questions are:
1) How can i realize file upload with JSF?
2) In which format a file is uploaded?
3) Can i use my java application for counting rows and columns number
of file?
Can you help me?Please use easy concepts because i'm inexpert.....
- 6
- JTable row selection (left and right mouse)Is it possible to be able to allow users to use either the left or the right
mouse button to select one or more
rows in a JTable, and upon the selection, be able to tell which mouse button
they used to select the row(s)?
I have 15 tables on the screen. The user needs to select one or more rows
from one table (the source)
and then the same number of rows in another table (the destination) and then
I need to swap the row
data from both tables. So, I need a way to differentiate between the
selections on the source and the
destination tables.
Thank you.
- 7
- Balanced TreeI was wondering if there were a built in (or freely available) library for
handling balanced trees.
I find many projects use them or could benefit from them.
:)
- 8
- Is it possible to write an applet that reads image and data files from web server that is easy for end users?My background:
4th year computer science student.
The school that I am studying at teaches a lot of java, but they haven't
ever touched upon applets. I don't have much experiance with applets and
I find that applets are excercising my patience. I thought I would
attempt to write an involved applet and the program I was writing was
working very well and I was pleased with the way it as coming out. I
then put it on a web server and discovered all of the security problems
with running applets off of the web. I am at a point now where I might
want to totally abandon the project using java and move over to c++ and
just write an app that uses an exe.
I have done a lot of searching on the net for the info that seems to be
eluding me. I am searching for and It is not clear to me if I can do
what I wish to do without all of the damn security exceptions.
My main question:
I want to develop an application that runs from a browser window as an
applet using Java. I want to be able to read files from the same server
and directory structure which has the html files. The files that I would
be reading would be jpg's and gif's and either text files or binary
files for the data. It would also be nice to write to the directory, but
at this point I would just be satisfied to be able to just read files.
The users that I expect to use this applet are not expected to be very
competant computer users. It is very important that the applet just run
from a link or other simple method. Can I do this from a jar file
without having to use certificates and/or java policy file
modifications.
I don't want to give up on java just yet, but this security thing is
killing it for me.
I have even thought about planting the data within the source code, but
that to me seems too damn messy, and just plain wrong.
I would just like if people could tell me one way or another if my
program would be possible.
Jean-Paul Lanaux
- 9
- PropertyChangeListener not recognizing changes to a putClientPropertyI must be missing out on something fundamental . . . why doesn't the
following code ever register a PropertyChangeEvent?
import java.beans.*;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.text.*;
public class PropTest extends JFrame {
private Boolean myBoolean = Boolean.FALSE;
public PropTest() {
super("PropertyChangeListener Test");
JPanel panel = new JPanel();
JButton button = new JButton(new BooleanAction("Button pushed"));
button.setText("Push me!");
panel.putClientProperty("myBoolean", myBoolean);
panel.addPropertyChangeListener("myBoolean", new BooleanListener());
panel.add(button);
panel.getInputMap().put(KeyStroke.getKeyStroke(KeyEvent.VK_SPACE, 0),
"space");
panel.getActionMap().put("space", new BooleanAction("Space
pressed"));
this.getContentPane().add(panel);
}
private class BooleanAction extends AbstractAction {
String title;
public BooleanAction(String title) {
super();
this.title = title;
}
public void actionPerformed(ActionEvent e) {
System.out.println(title);
System.out.println("Old value: " + myBoolean.toString());
myBoolean = new Boolean(!myBoolean.booleanValue());
System.out.println("New value: " + myBoolean.toString());
}
}
private class BooleanListener implements PropertyChangeListener {
public void propertyChange(PropertyChangeEvent e) {
System.out.println("Hey, you changed my value!");
}
}
public static void main(String[] args) {
PropTest propTest = new PropTest();
propTest.setResizable(false);
propTest.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
propTest.pack();
propTest.setVisible(true);
}
}
- 10
- Static fields accessed by getter/setter...what happens?(apology for duplicate post, I felt I posted in the wrong forum earlier.)
Could someone please enlighten me as to what will happen if I have:
public class MyClass
{
public static String someName = null;
public void setSomeName(String s)
{
someName = s;
}
public void getSomeString()
{
return someString;
}
}
I'm not sure how the static field is being handle using non-static getters/setters.
Thanks
Stacey
- 11
- JAVA ?Oracle Programmers wantedHighly experienced JAVA / Oracle programmers wanted for a three month
contract in South Africa (JHB). Must have had ERP experience with some
integration skills.Open source experience an added advantage. Must be able
to work in a team.
Email CV to email***@***.com
- 12
- checkbox ploblem pls help!!i was new in java and i now completed add the checkbox in each node but the
ploblem is i cant click the check box..
what should i do in next step... pls help me thank you..
following is my code
fileTree.setCellRenderer(new DefaultTreeCellRenderer()
{
public Component getTreeCellRendererComponent(JTree tree, Object
value,
boolean sel, boolean expanded, boolean leaf, int row, boolean hasFocus)
{
super.getTreeCellRendererComponent(tree, value, sel, expanded, leaf,
row, hasFocus);
JCheckBox chk = new JCheckBox();
chk.setContentAreaFilled(false);
chk.setEnabled(true);
//
chk.setBorderPaintedFlat(true);
chk.setOpaque(false);
JPanel jPanel = new JPanel(new BorderLayout());
jPanel.add(chk, BorderLayout.WEST);
jPanel.add(this, BorderLayout.EAST);
return jPanel;
}
--
Message posted via http://www.javakb.com
- 13
- HalfTruth=Lie (was: I'm still waiting for somebody to offer co...)> From: "Phlip" <email***@***.com>
> The good is the enemy of the best.
A half-truth is a lie.
A bicycle with only one wheel isn't useful.
Yin without yang isn't useful.
A glass half full but not half empty, or vice versa, is not the whole
picture.
For nearly every cliche there's an opposite which is equally valid in
different circumances.
Please choose which of the following activities you would most and
least like to participate in:
(1) Have bamboo shoots driven up under your fingernails.
(2) Undergo Chinese water torture.
(3) Be trapped in a large tank with one (1) pihrana.
- 14
- JavaDoc Ignore TagsHi all,
Is it possible to tel JavaDoc to ignore certain XDocLet tags, and/or not raise a warning that it is
unknown?
I am currently running JavaDoc through an Ant task, and wish to hide the warnings about my
@hibernate tags.
Regards,
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- sample jsp servlet application requiredHi geeks,
I'm a beginner in jsp and servlets, i want a sample JSP-SERVLET
applicaton with source code. Can you please tell me where can i get the
sample applications.
Thanks in advance...
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