SDN Share: all posts

Text to Image

Jamwa — Fri, 20 Feb 2009 04:19:44 PST

Simple class to convert a String into an image. Useful scenario is when you want to "hide" an email address on a web page from bots.

Search Engine Friendly URL Using Java Technology

Istiaque — Tue, 17 Feb 2009 22:45:33 PST

This writing is trying to solve a typical issue while using Search Engine Friendly URL in web application Using Java Technology

KeyListener in JComboBox

castever — Tue, 17 Feb 2009 09:09:53 PST

adding a KeyListener to a JComboBox

Unzip using java

jevat — Thu, 22 Jan 2009 03:52:07 PST

This code snippet shows an easy way to unzip a folder stucture with any depth using Java. It uses regular expressions that may differ for different platforms (JVMs), but this one worked on my Windows XP (for other JVMs you might have to change "\\\\" to "\\" or even "\\\\\\\\". I post this piece of snippet since I couldn't find one working example for unzipping a .zip file that may contain a folder structure of any depth! The problem with the existing solutions is the assumption that the zip file is a "one-level-deep" folder structure, i.e. one level of folders and their file contents. They couldn't handle folders containing folders containing folders etc.

Needed imports: import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.util.zip.ZipEntry; import java.util.zip.ZipInputStream; import java.io.FileNotFoundException; import java.io.IOException;

Recovery from an OutOfMemoryError

AndrewThompson64 — Tue, 13 Jan 2009 07:02:43 PST

The JavaDocs for Error state, in the first sentence..

"An Error is a subclass of Throwable that indicates serious problems that a reasonable application should not try to catch."

This advice has led to the fallacy that an OutOfMemoryError should not be caught and dealt with. But this demo. shows that it is quite easy to recover to the point of providing the user with meaningful information, and advice on how to proceed.

I aim to make my applications 'unreasonable'. ;-)

Prompt the user for an entire directory of files

AndrewThompson64 — Fri, 9 Jan 2009 18:24:22 PST

There are many occasions that an application requires a group of source media files to do it's job. Examples might be an image slideshow, a music jukebox, or a multi-pane document displayer.

This little demo shows a relatively easy way to prompt the user for an entire *directory* of source files to load, with the file types determined by file extension.

Simplified for purposes of demo. For general use, this code should be significantly refactored.

Easy Map

mikha_the_mike — Fri, 9 Jan 2009 08:46:23 PST

a generified one-liner to create maps of any size

Client-Side Architecture

Pilla.Gurumurty.Patrudu — Wed, 7 Jan 2009 23:05:32 PST

Java is an extraordinary programming language, and has remarkable success, on the server side. Earlier notions of the industry, that server holds everything and the client is a mere dumb browser, is fading rather quickly. Smart client technologies based on JavaScript are mushrooming day by day. There is currently a notion, on internet, that JavaScript is the future client, and jsp�s, web-services are servers, implying that java has no place on client side. Ironically, script engines rely on java, or have learnt many lessons from java. I feel that the client side, has a highly disorganized array of technologies, which could hamper development. In this article, I describe a neat idea on client side programming, using java.

Top things to know about the String class!

deepak_1your.com — Wed, 24 Dec 2008 02:36:15 PST

Most important facts about the most common class - String

Few things about toString()

Vayush — Sun, 21 Dec 2008 23:18:10 PST

Description toString() method and its types.

Capture image of component

AndrewThompson64 — Tue, 2 Dec 2008 23:38:42 PST

This simple code shows how to gain a BufferedImage of a Component.

The main() goes on to save the image as a .png file.

In case the formatting of code samples is still getting messed up here on the SDNShare site, you can also see the (formatted) source here.. http://pscode.org/fmt/sbx.html?url=/test%2Feg%2FComponentImageCapture.java&tab=2

Introdution To JSTL

Yuval_Zilberstein — Fri, 24 Oct 2008 15:17:37 PDT

Introdution To JSTL

jsapi masking() ext,flankers,premaskers and postmaskers

schizodog — Sun, 12 Oct 2008 07:53:27 PDT

i'm an MD and this is a sample code i used to remove masking on my sound card,experiments in psychology are yet to determine the efficacy of masking in real ilfe situation,will welcome any corrections or contributions

How to Change a Java Program into Reusable API

amajko — Mon, 22 Sep 2008 14:47:40 PDT

I am a mid-level java programmer who has come up with ways of improving my beginning java programs. One way is the expand the specifics of a Java program so that it can be used as an API, callable by other programs. This gives a flexibility to that program it hadn't had before. I am a test engineer for Java applications and have written many test plans and summary documents on various Java test cycles.

JSE Should have a Delimited File Class

extendJAVA — Mon, 22 Sep 2008 09:56:52 PDT

This class provides a Delimited File. It extends java.io.File and allows the user to use any String or char for the delimiter.

The Vibrating JFrame

Jamwa — Fri, 12 Sep 2008 10:12:07 PDT

Ever used msn messenger? Ever been "nudged" by the person you are chatting with? I bet so. Seen how the chat window vibrates on a nudge? Well, I have tried to replicate the vibrating effect with Java code. Enjoy

Law of Demeter Explained

N_i_X — Wed, 10 Sep 2008 11:17:14 PDT

Law of Demeter helps developer in ensuring encapsulation in day to day work.

Overriding Tip [Million Dollar Tip]

N_i_X — Wed, 3 Sep 2008 22:20:40 PDT

This is useful while overriding any class.

Don't use java.util.Stack class

N_i_X — Sat, 30 Aug 2008 23:35:51 PDT

java.util.Stack class is badly implemented in Java collection framework. This tech tip explains why not to use Stack class.

Strange Socket Behavior and Solution.

N_i_X — Mon, 25 Aug 2008 02:26:20 PDT

About Socket behavior.

LinkLabel Using the Desktop Class

AndrewThompson64 — Sat, 23 Aug 2008 02:01:44 PDT

There are a lot of link labels. This one uses the Java 1.6+ Desktop class for its functionality, and is thereby suitable for applets, applications launched using JWS, and 'standard' (non-JWS) desktop applications.

Defensive Loading of Trusted Applets

AndrewThompson64 — Sat, 16 Aug 2008 00:51:22 PDT

An example of loading trusted applets in a 'defensive' way, so that they provide logical feedback to a user who refuses the digitally signed code.

This applet provides a JEditorPane to view documents identified using a JFileChooser. If the user decides not to Run the digitally signed code, a standard message will be displayed in the JEditorPane to indicate what needs to be done, to enable the trusted version of the applet.

See also the live demo at http://pscode.org/test/docload/

Comma Separated Values (CSV) Splitter

corlettk — Thu, 7 Aug 2008 07:12:35 PDT

This is just another Whatever Separated Values string splitter. I thought someone might find it useful. It's only mark of distinction over the others (there are plenty) which I've looked at is they all trim the field-data, in this one trimming is configurable, apart from that it's an example of "raw" string parsing using Java. Tested on 1.6.0_04-b12 on Vista Pro.

Store Application Settings and Components

AndrewThompson64 — Sat, 26 Jul 2008 05:44:26 PDT

How do I find the application path?

This is a FAQ related to storing application configuration files, or accessing tools (e.g. a database or plug-in directory) used by an application.

The 'smart answer' to this question is "store the data in a sub-directory of user.home, based on the package name".

This is not a direct answer to the original question, but it is usually the best strategy to achieving a solution. Finding the application's path is tricky, and usually unnecessary.

Having provided this advice many times, I decided to write the code that implements it. After all - it is easier to link to an example, than to explain!

Page Navigation

Jayaganesh — Fri, 25 Jul 2008 04:26:32 PDT

This code sample navigates the number of pages listed from database contents in a JSP page in an efficient way.

Show Exported Date of a Oracle Dump File

thiru.k — Sat, 12 Jul 2008 13:09:45 PDT

Code sample to show oracle dump exported date.

TNSNames.ora parser

thiru.k — Sat, 12 Jul 2008 13:05:46 PDT

Oracle tnsnames.ora parser.

ScriptEngine JavaScript Evaluator

AndrewThompson64 — Fri, 11 Jul 2008 10:26:36 PDT

Example of using the ECMAScript (JavaScript) engine provide in J2SE 6 to evaluate simple JavaScript expressions.

The ECMAScript engine is the only one available 'out of the box', but others can be added using the service provider mechanism.

Dynamic width JComboBox

david_david — Thu, 10 Jul 2008 23:43:45 PDT

The popup of the JCombo will automatically increase its width according to its items width. It is useful to view the items to its full length.

JComboButton is an arrow button.

Applet Minimum Version Checker

AndrewThompson64 — Sat, 5 Jul 2008 09:07:55 PDT

An applet to check the Java version is the minimum needed to run another applet of interest. If not, it will redirect to a help/download page specified in the applet element.

This code is compatible with Java 1.1.

Using Grinder to Load Test a J2EE Web Application

Divya.Lekha — Mon, 30 Jun 2008 05:25:37 PDT

The article covers the approach we followed, learning, and issues we acquired in load testing using Grinder framework.

Do You Need to Parse XML to Get its Root Element?

javajava1 — Mon, 30 Jun 2008 03:24:15 PDT

This code is used to read the XML root tag of each input xml file. It uses a SAX parser for parsing files.

Implementing an XML FileName Filter

javajava1 — Mon, 30 Jun 2008 01:36:35 PDT

Sample code to write a filename filter to check for xml files, in other words check for files with extension .xml.

Sending Messages to a JMS Queue

javajava1 — Sun, 29 Jun 2008 22:49:00 PDT

Given is the code to connect to a JMS Queue. Object and send messages to the Queue.

Service Locator for the JNDI Tree

javajava1 — Sun, 29 Jun 2008 22:04:46 PDT

This class is implemented as a singleton class and is a central place for looking up objects in the JNDI tree. A useful utility which can be used to search EJBs, datasources or any other JNDI utilities in the JNDI tree.

Property Utility to Read Properties Files

javajava1 — Sun, 29 Jun 2008 21:55:00 PDT

This utility reads the property from the specified property file and returns the read object against the key. This utility can be used directly out of the box without any code changes.

Servlet to Output form Parameters

javajava1 — Fri, 27 Jun 2008 03:43:00 PDT

Sample servlet to get the parameters submitted via a html form and display those. A form should post parameters like txtUser and txtEmail to this servlet

Java Object Serialization

javajava1 — Fri, 27 Jun 2008 03:05:34 PDT

Sample code to test serialization and de-serialization in Java.

Send a Message to a JMS TOPIC for Asynchronous Communication

javajava1 — Fri, 27 Jun 2008 01:24:46 PDT

A sample utility to send a message to a peconfigured JMS topic on the Message Server. These messages will then be picked up by a subscriber or a message driven bean listening to that topic. The topic "jms/mytopic" should be configured on the server and appropriate url, security details and context factory details of the server need to be provided.

How to Have a Dynamic Client for a Web Service

javajava1 — Fri, 27 Jun 2008 00:18:45 PDT

A sample web service client which is dynamic in nature. On having a set of operations that can be invoked on a web service and on knowing the endpoint url any web service can be invoked without having to create a static client. The assumption here is that there is a web service called Company at the given url which exposes a addEmployee() operation to add an Employee and returns a string result. Since the url and the operation, both are string inputs this can be easily modified for any Web Service.

ZIP Compressor and Decompressor

javajava1 — Fri, 27 Jun 2008 00:06:49 PDT

A very useful utility for compressing, decompressing and creating xml using the ZIP APIs of Java.

Simple HttpHandler for Returning Content of a URL

mlk — Thu, 26 Jun 2008 06:02:25 PDT

Recently I needed to test an application that interacted with a web server. So to test I required a simple web server and Java 6 comes with one built in. The one built in to Java 6 requires handlers and I could not see any simple "return this file" type ones built in, so I made one. It and a simple test case are included below. Enjoy.

HTTP Headers from Browser to Web Server

javajava1 — Mon, 23 Jun 2008 21:39:44 PDT

Sample code to display http headers submitted by the browser to the web server.

Sample to Have a Servlet Output an Excel

javajava1 — Mon, 23 Jun 2008 21:34:05 PDT

A sample servlet to emit out data in xls format. Check out the code.

Home-Made AOP

g_baud — Fri, 20 Jun 2008 12:08:36 PDT

Rationale and fundamentals of AOP. Shows a simple AOP infrastructure implementation using only core Java libraries.

File Operations - Working With Files in Java

javajava1 — Fri, 20 Jun 2008 03:04:09 PDT

This is sample code to display how to work with files in Java, like creating and deleting files, listing directory contents and so on.

XML Schema Validator, Validating XML Files

javajava1 — Fri, 20 Jun 2008 02:56:10 PDT

A very simple utility to validate XML files against a given XML schema also called as the XSD. The reference to the XSD is provided in the XML file and this utility will validate the XML against that XSD.

Instant Equals Method

g_baud — Thu, 19 Jun 2008 23:27:30 PDT

Using EqualsBuilder to facilitate object equality comparisons.

Collection Size in Expression Language

g_baud — Thu, 19 Jun 2008 20:06:40 PDT

Accessing collection sizes through Expression Language (EL) in JSP or JSF.

My Own XML Parser

javajava1 — Thu, 19 Jun 2008 04:06:13 PDT

I had once written a basic XML parser and thought that I should share it with you. It is a simple parser and very good to know if you want to understand XML parsing basics.

A Useful Reflection Utility

javajava1 — Thu, 19 Jun 2008 03:59:56 PDT

This is a UI based utility application to test any class & its methods; to invoke the methods and obtain the results.

Boolean.TRUE or new Boolean(true)

javajava1 — Thu, 12 Jun 2008 01:09:58 PDT

Is it better to use the constructor or the static field while creating a boolean object? Small as it may seem this and other such instances can surely improve the performance of your application.

Sample to Create a SOAP Envelope Using SAAJ API and Send it to a Web Service

javajava1 — Sun, 8 Jun 2008 21:06:37 PDT

This is a sample Java code to create a SOAP envelope consisting of header and body and invoking the add method on a Calculator Web Service, which is already hosted. By replacing the url and adding more information to the body any Web Service can be invoked.

Converting Property File to XML

biju74 — Wed, 4 Jun 2008 20:40:40 PDT

Previously configuration data were stored as Property Files. Now-a-days it has been changed to XML. If you need to convert the existing property file to equivalent XML files, you can use the following code.

File Compression Utility

biju74 — Wed, 4 Jun 2008 02:59:28 PDT

This module can take any file as input and compress it into a zip file. It uses ZipOutputStream for compression.

Developing a Protocol for a Network Application

ggomez — Tue, 27 May 2008 17:31:10 PDT

Most of the advantages in Java are based in the facilities that give to the programmer for transfer data through the internet. But, even with Java keeping the connection and keeping track of all the packets that are received, it�s almost for sure that your application is going to need some kind of mini-protocol that communicate to your other application that you�re going to send text, a file, or maybe something that you don�t want to show to the user, like an update or a log file. A command based protocol is usually the first plan, most of the protocols work sending a command and a certain number of parameters, this make the remote application do something, like responding or something else.

JSF? What is it and how is it used?

javajava1 — Sun, 25 May 2008 21:26:35 PDT

JavaServer Faces technology is a server-side user interface component framework for Java technology-based web applications. This is sample code to demo the use of JSF.

Java Performance Tuning - A Practical Approach

bobypt — Tue, 20 May 2008 21:10:30 PDT

A practical guide to Java performance tuning.

Folder Change Detector

Jamwa — Mon, 19 May 2008 04:05:18 PDT

This simple program polls a given folder in order to detect any new files added into it.

'ScanArchive' a Utility Program to Search Files with in the .jar or .zip Files

pradeep.k — Wed, 7 May 2008 22:27:05 PDT

This small utility program can be used to search files with in the archive files. This can be used at the time of project development for searching .class files with in the large set of jars in the project.

Swapping Two Integer Variable Values Without Using a Temporary Variable

R34GTR — Tue, 6 May 2008 02:44:35 PDT

This class helps you to swap two integer values without using a third or a temporary variable. Here I have used the xor operator to achieve this. When swapping two variables you can use the xor operator like this so that you can reduce the cost of declaring another variable as it will take another memory point as well as after swapping the two variable values the third temporary variable gets obsolete and it is an unwanted cost.

Most Common Mistake With "if condition checking"

N_i_X — Mon, 28 Apr 2008 17:58:47 PDT

Are you writing "if conditions" in the right way? If you feel so, then also go through this TechTip. It will give you correct picture about it.

Catching Unhandled Exceptions

N_i_X — Wed, 23 Apr 2008 14:16:15 PDT

How to catch unhandled exceptions in any application.

Encoder and Decoder Text in Base64

copernico — Sun, 13 Apr 2008 09:15:07 PDT

Encodes a string of plain text codified a chain based 64. It's a class that contains a JFrame and two JTextArea.

Sample Code to Send Email

javajava1 — Wed, 2 Apr 2008 21:43:58 PDT

This is a small and concise sample code to send an email with attachment. It uses the Apache email libraries for accomplishing this.

System.out.printf()

Mahendra_Kariya — Wed, 2 Apr 2008 03:26:17 PDT

This new feature is introduced from J2SE 5.0.

JSP Database Page Generator

Jamwa — Tue, 1 Apr 2008 05:16:05 PDT

Do you ever display entries from a database into a jsp page and then realize that the rows are far to many so your page takes forever to load?

This TechTip will show you how to generate the pages automatically depending on the number of entries that you have. Comprising two pages, index.jsp will calculate the number of entries and call show.jsp which does the actual displaying of the pages.

Replace the variables with what suits your needs.

Compiling Applications Using GTK with Sun Studio

bnBertha — Thu, 20 Mar 2008 06:29:48 PDT

The GTK FAQ recommends adding `pkg-config gtk+-2.0 --cflags --libs` to the compile command line. Although this works, it doesn't really fit in with the ethos of separate compile and link configuration settings with Sun Studio.

Data Access Object Code for JPA

SyedSaifuddin — Fri, 14 Mar 2008 23:33:40 PDT

The is generic class to add, edit, delete and manipulate any object.

An example for each method is;

daoBean.addObject(user); daoBean.addObject(invoice);

daoBean.deleteObject(user,userid);

daoBean.deleteAllObject(user,userid[]);

List cols = new ArrayList(); Map condition = new HashMap(); cols.add("username"); cols.add("password"); condition.put("username", userId); condition.put("password", passwd); User user = (User) dao.getObjectByMapCondition(new User(), condition, cols);

Cancel Print Requests

SundoNuno — Fri, 14 Mar 2008 14:51:19 PDT

Information on canceling print requests.

Java Scripting Support Usage Example

kirill.klenski — Thu, 13 Mar 2008 03:54:17 PDT

A small code snippet illustrating the usage of Java scripting engine included in JDK 6 distribution.

Change the Length of a Password

SundoNuno — Wed, 5 Mar 2008 08:00:14 PST

This TechTip covers how to change the length a password.

Change Solaris DNS Client Settings

Rajeeva — Tue, 4 Mar 2008 17:35:54 PST

Here's how to change Solaris DNS client settings (resolv.conf).

How to Generate a Unique ID

javajava1 — Thu, 28 Feb 2008 20:51:50 PST

The code below provides a mechanism to generate a unique string ID based on the IP address of the machine, the date and time and a random number.

JAVA Programmers Do it With GWT

k-e-n — Sun, 24 Feb 2008 18:58:14 PST

How to call Java server-side methods from a web client without touching JavaScript, HTML, or CSS.

Creating a Table Model Using javax.swing.table.AbstractTableModel

R34GTR — Fri, 22 Feb 2008 11:16:52 PST

This table model class has extended javax.swing.table. AbstractTableModel class and override the AbstractTableModel methods to use with the custom object class. By using this model it is easy to develop a JTable.

Arrays vs Collection For Primitive Types

javajava1 — Wed, 20 Feb 2008 20:12:19 PST

Creating the instances of wrapper classes for primitive types and then adding them to a collection is more time consuming, instead arrays of primitive can be used. This will not only occupy less memory, execution will also be fast.

Pass by Value or Reference

virag — Tue, 19 Feb 2008 06:59:41 PST

We discuss about object parameters being passed by value or reference.

Generics, Enhanced for Loop, C Style Formatting in JDK 1.5

javajava1 — Mon, 18 Feb 2008 20:01:54 PST

JDK 1.5 features like generic types, an enhanced for loop, C style formatted input/output are described briefly in this article with appropriate code samples.

Why No Null Check Before Instance of Operator?

javajava1 — Wed, 13 Feb 2008 20:43:22 PST

Why null check is not required before the instance of operator.

A JTree Model Wich Allows Only Leafs to be Selected

melqkiades — Mon, 11 Feb 2008 08:46:47 PST

This small class will allow you to build a JTree that does not allow parent nodes to be selected, just leafs.

Call Java APIs from JavaScript via AJAX

aharihar — Tue, 5 Feb 2008 12:46:48 PST

In this article, we discuss the details on invoking a Java APIs from Javascript via AJAX.

Faster Mechanism To Create Double Object

javajava1 — Sun, 3 Feb 2008 19:57:08 PST

Creating Double object using the double primitive type vs. the string constuctor

Avoid Checking Null When Using Instanceof

R34GTR — Thu, 31 Jan 2008 03:54:54 PST

void sampleMethps(String param) {

if (param != null) { /// NO NEED OF THIS LINE

if (param instanceof String) { // YOUR CODE GOES HERE } } /// NO NEED OF THIS LINE }

EJB 3.0 Features

javajava1 — Wed, 30 Jan 2008 20:05:07 PST

This article briefly covers the important aspects of the EJB 3.0 specification. The article provides an overview of the new or enhanced features available in the EJB 3.0 specs

Daylight Saving Time and Date Based Calculations in Java

javajava1 — Tue, 29 Jan 2008 02:41:26 PST

This article talks about daylight saving time and how it effects date based calculations in Java.

Autoboxing and Auto-Unboxing of Primitive Types

Mari — Mon, 28 Jan 2008 00:36:49 PST

A short code sample to denote how autoboxing and auto unboxing of primitve types can be done.

JPEG Image Save Using Java.imageIO

Napagoda — Mon, 21 Jan 2008 03:17:32 PST

Alternative code for com.sun.media package.

Numeric Input With JTextField

aranovB — Mon, 14 Jan 2008 08:05:03 PST

How we can filter user input on a JTextField to allow only numbers to be entered.

We create a class derived from PlainDocument (NumericInputDoc) and set the document of our JTextfield object like this:

numInput.setDocument(new NumericInputDoc());

Simple Directed Graph Implementation

Pau_carre — Fri, 11 Jan 2008 10:50:15 PST

Simple directed graph implementation that uses collections and generics.

Accessing Remote Java EE Beans

merturk — Tue, 1 Jan 2008 06:03:14 PST

Hello everyone, here it is a quick info about how to access remote Java EE beans using JNDI lookup.

Avoid Null Pointer Exceptions While Comparing String Data With Constants

kirankumarr — Fri, 28 Dec 2007 08:15:08 PST

When we compare data with constants we can avoid Null pointer exceptions by following this simple technique.

Need of Thread Pools

Nistelrooy — Tue, 25 Dec 2007 23:20:17 PST

This tech tip explains the need of thread pools and where they should be used.

How To Get Remote User From Entity Beans

merturk — Sat, 15 Dec 2007 13:25:37 PST

Hi everybody, this is a simple entity bean retrieves authenticated user information.

Progress bard, Keyboard

artemb — Mon, 10 Dec 2007 13:18:40 PST

Progress bar with lights on keyboard

Browse All Files In A Directory and Sub-directory

artemb — Mon, 10 Dec 2007 12:51:22 PST

Browse all files in a directory and sub-directory and do something to file.

RSS Reader, HTTPURLConnection

sriprasad — Mon, 10 Dec 2007 08:35:42 PST

This code snippet briefs how to create URL object, HTTPURLConnection and how to retrieve RSS feeds of a given RSSURL. This sample can be used to implement desktop NewsReader/RSS Reader applications.

Writing a String[] To A File

1cMas5_cow — Wed, 5 Dec 2007 12:34:22 PST

This code will write a String[] to a file.

Loading Resources From Your JAR File

1cMas5_cow — Wed, 5 Dec 2007 12:25:36 PST

How to load a resource from the application's JAR file.

More Efficiency With A Dedicated Variable Object

1cMas5_cow — Wed, 5 Dec 2007 12:11:49 PST

This simple solution can save lots of time and code.

Animating Swing components (Part 2)

Nelbins — Mon, 3 Dec 2007 07:24:32 PST

In Part 1 I showed how to write a class to animate JComponents. This method is good because it can be used to animate any JComponent, allowing you to use a single class to animate several different components and create a theme to your GUI. The disadvantage of this method is that it's animation capabilities are restricted to the methods in JComponent such as setBackground(). Any attempt to use the Graphics object to paint won't work as Swing will paint over anything you do.

Here I will demonstrate how to write a more powerful animation class, but with the disadvantage that it is restricted to individual JComponent implementations, such as a JButton.

Animating Swing Components

Nelbins — Mon, 3 Dec 2007 07:01:17 PST

Standard Swing components are fine, but sometimes you need to perk up your GUI with components which stand out from the rest. How about adding some animation to your JComponents?

Here I will demonstrate two different approaches to animation and provide examples of both.

Adding New User Account To Solaris

Rajeeva — Mon, 26 Nov 2007 21:44:35 PST

This tech tip describes how to add a new user to the Solaris system.

Send Junit Results to Log File Using ANT

thinkblock — Mon, 26 Nov 2007 21:43:59 PST

If your Junit tests are producing very long out put in the console you will have problems trying to figure out where all the exceptions happened. It would be great if you can direct the output to a log file. You can use an ANT `logfile` option to do this.

How to use SwingWorker Thread?

simplestring.com — Mon, 19 Nov 2007 10:58:43 PST

This is the simple example to use the SwingWorker thread in Swing applications. The SwingWorker.java is not a part of JDK, you need to download it. I also attached the SwingWorker.java code.

Pop-up Toolbar

jkost — Thu, 15 Nov 2007 01:52:32 PST

This is the code of a pop-up toolbar that is used when there is no space left in your toolbar and you wish to group buttons together in one button. When the button is clicked the toolbar pops up with a group of buttons for you to choose. It accepts an array of Actions, or JButtons, to be added to the toolbar. You can modify the size of the buttons, hence of the toolbar.

Float/Double To Rounded INT Without Math.Round() (Logical)

Amit.Panchal — Fri, 9 Nov 2007 10:11:03 PST

The following code demonstrates how one can cast a float/double to a rounded int without Math.round().

Swapping Two Int Variables Without Extra Variable (Logical)

Amit.Panchal — Fri, 9 Nov 2007 09:48:18 PST

Following code demonstrates how one can swap 2 int variables without using a temporory variable in a code.

Hacking the JComboBox Renderer

Amigo — Wed, 7 Nov 2007 11:48:31 PST

Hacking the JComboBox Renderer to customize your display

Nice Execute SQL Query Method

Slawomire — Fri, 2 Nov 2007 05:37:36 PDT

This method can execute sql query and return list of user specified beans. You can specify your sql parameter in object table, and define a bean class.

Universal Execution of SQL Query

Slawomire — Fri, 2 Nov 2007 04:30:57 PDT

Simple method that execute sql statement and return list of bean that are results of this query.

When to Use Weak References with Listeners

Amigo — Tue, 30 Oct 2007 11:49:35 PDT

When to use Weak References with Listeners and when not to use them

Generate Basic Getters and Setters More or Else Similar to Eclipse

prashant_jalasutram — Mon, 29 Oct 2007 07:24:42 PDT

Sample Code generates getters and setters given a field name. Though not perfect but shows may be how Eclipse achieves this feature.

Loading Jar Files To Classpath

R34GTR — Wed, 24 Oct 2007 22:37:31 PDT

This class will help you to add the location of your jar file/s to an arraylist and the program will automatically load it to the system classpath.

How to Get Arrylist Object in Java Program From Servlet When Using URLConnection For Calling Servlet By Java

navinmail — Thu, 18 Oct 2007 04:01:58 PDT

How to get arrylist object in Java program from servlet when using URLConnection for calling servlet by Java.

Performing A LDAP Search Using Java

ashwini83 — Tue, 16 Oct 2007 02:19:47 PDT

The Java Naming and Directory Interface or JNDI was introduced with Java 1.3. As the name suggests, it provides naming and directory functionality to Java programs in an implementation-independent manner. JNDI provides very good access to LDAP directories.

The following is a simple example program which executes an LDAP search based on search filter arguments and displays an attribute from the result returned.

How To Create Own MP3 Player Using JMF 2.1

RajeshKrGupta — Thu, 11 Oct 2007 16:48:27 PDT

When I used the the Linux, I saw there was not any "MP3 player" which was ease to use like "Window Media Player" and other players on "Windows Platform", here is a code sample to create your own MP3 player by using Java Media Frmaework 2.1 which unique functionality of "Platform Independency".

NOTE: To deploy this code you must have installed JMF 2.1. This code is tested on NetBeansIDE 6.0 Beta 1.

Using FileWriter to Write to a File

tygerberg — Thu, 11 Oct 2007 11:00:38 PDT

This code sample shows a different way of using FileWriter. It's very easy writing to files using this method.

Connect to a FTP Site Via Proxy With Authentication

seemant_shrivastava — Wed, 10 Oct 2007 02:55:03 PDT

Connect to a FTP site via proxy with authentication.

Singleton Defeated in Cluster Deployments

gsluthra — Thu, 4 Oct 2007 23:19:48 PDT

How depending on a singleton can land you in trouble when your application is deployed in clustered servers.

Type Password Will Take **** While We Retrieving

Vijay9999.vijay9999 — Thu, 4 Oct 2007 05:12:17 PDT

Type password will take **** while we retrieving this value using request we will get exact typed password in between this what is happening.

Finding GMT time Irrespactive of Timezone Including Daylight

Vineet_Goel — Mon, 1 Oct 2007 17:09:19 PDT

Finding GMT time is difficult as there is no straight API available which calculates the GMT time.

Saving Images

artemb — Sat, 29 Sep 2007 10:07:28 PDT

Saves images from a web page.

Pythagorean Triplets Generator

artemb — Fri, 28 Sep 2007 18:48:47 PDT

Generates a list of triplets(a,b,c) where a

Digital Signature Serialization Deserialization To - From File

Jose_paul — Fri, 28 Sep 2007 00:52:22 PDT

Code snippet explains writing the signature, original data, signed data to files and read it back.

Then verify the signature.

Acquiring pixel data from an Image object using PixelGrabber class

nddprasanth — Wed, 26 Sep 2007 04:00:48 PDT

PixelGrabber class available in java.awt.image packate can be used to access pixels of an Image object. PixelGrabber class can acquire pixel data synchronously or asynchronously. It can store pixel values in a user-specified array or create a suitable array itself.

The following example shows how to use PixelGrabber class to get pixel data from an Image object.

How to Use Mouse Events in Swing

nddprasanth — Wed, 26 Sep 2007 03:57:11 PDT

Mouse events are generated by the following types of user interaction:

*A mouse click *A mouse entering a component's area *A mouse leaving a component's area

Any component can generate these events, and a class must implement MouseListener interface to support them.

Alphanumeric Validation in Javascript

nddprasanth — Wed, 26 Sep 2007 02:15:46 PDT

This function can be called whenever you want to validate a textfield from entering alphanumeric values.You just need to specify the characters that are allowed to be entered in the "else if" part in the code.

Swapping Two Integers In One Statement Without Using A Temporary Variable

indianium — Tue, 25 Sep 2007 21:57:58 PDT

Just a language hack

Using Final in The SWITCH Statement

jindagi — Tue, 25 Sep 2007 21:54:09 PDT

I have found something good regarding COMPILE time checking of BREAK statements in SWITCH statement (for some conditions).

Distance Between Two Geographic Points

Baiborodin — Mon, 24 Sep 2007 16:12:26 PDT

Do you need to calculate distance between two points on the map but you don't know how to do it? It's very simple task.

Process EJB QL Query That Returns More Than One Item

Saeed_Zarinfam — Wed, 12 Sep 2007 11:15:14 PDT

Process EJB QL query that returns more than one item.

Find The File Path Of A Given File Name Inside A Root Directory/Directory

R34GTR — Wed, 12 Sep 2007 01:50:13 PDT

This utility class helps you to Find the path of a given filename with its file extension in a given root directory. The user has to provide the root directory he wants to search for and the filename with its extension (ex: letter.doc ) to lookup for which will return the exact path the file resides in your system. The beauty of the program is that once an instance of the FileFinder class is created it will not worry about loading the file structure again which will speed up the file search.

Shuffling Elements of an Array

.@_ — Tue, 11 Sep 2007 03:17:08 PDT

Very simple way to shuffle elements of an array of any kind of object.

Attach an Entity With Merg() Method (for method parameter)

Saeed_Zarinfam — Sun, 9 Sep 2007 01:26:58 PDT

EntityManager.merge() method cannot attach method parameter.

Sun App Server (or Glassfish) Windows Service Problem (when log off server)

Saeed_Zarinfam — Sat, 8 Sep 2007 21:50:32 PDT

Problem: When Sun Java application server or Glassfish installed on Windows 2003 server as windows service works proper, but when the user logs off, the application server does not have any service.

HOWTO: Ensure Correct JAVA Look and Feel at Program Startup

uuklanger — Fri, 7 Sep 2007 07:12:35 PDT

Lets face it, the default Java Look and Feel kind of sucks. It looks ok but when you have it next to a native app, it sticks out. Fortunately, the guys at SUN have made it easy to setup your JAVA program to automatically use the system look and feel.

HOWTO: Use Netbeans and ANT to Auto-run Jarsigner

uuklanger — Fri, 7 Sep 2007 06:46:08 PDT

There are times when you need to sign jar files. In my world it is is all the time since I tend to favor Java WebStart applications. There are techniques using ANT to auto sign JAR files, however, they require you to include your store password which is ok if your code remains internal but may not be so good if you post it to Google Code.

To get around this, there is a pretty easy to implement solution. I, being the Netbeans fan, will describe it from the Netbeans perspective, however, ANT is ANT so it should work using anything.

Creating Documentation with a WIKI System

utta — Thu, 6 Sep 2007 11:15:29 PDT

A project wiki is a good method to create an alive documentation for a software product. On JavaForge there is a good example wiki, designed for collaborating in documentation issues for an open source project. This is made available by the underlying collaboration platform CodeBeamer.

An Interesting Way To Draw a Complex Shape In 2D Graphics

pravinth — Fri, 31 Aug 2007 13:58:11 PDT

There are many ways to eliminate the difficulties in drawing complex shapes. Here only a single sector of a circle based image is defined and using this all other similar sectors are drawn.

What To Do If NIS User is Not Getting His Home Directory

SATEESH-CONSOLE — Wed, 29 Aug 2007 09:12:24 PDT

If a NIS user is getting a "/" instead of their home directory, this is what an administrator should do to resolve the problem.

Finding the Datetime Difference Between Two Dates

R34GTR — Mon, 27 Aug 2007 00:41:54 PDT

This class will provide you with an integer value for date time differences using java.util.Calendar class. You only have to provide the two date time values you want to find difference for plus the locale, timezone and the differential type such as in years or months, etc.

Using StyleConstants to Add Color to a JTextPane

andrew_malcolm — Sun, 26 Aug 2007 01:58:38 PDT

A subclass of JTextPane that allows output in color, complete with a test program.

Java Code to Grab Google Search Result (Not as Simple as It Appears)

TheZhang — Sat, 25 Aug 2007 23:15:15 PDT

It seems we can use standard class URLConnection to retrieve the content of a Google search result page. In fact it does not work. Google web server check for the User-Agent http headers before sending out response. The default user agent of JVM is "Java Agent", hence Google rejects the request by a 403 error code.

To get around with this, one simple way is to use the -D"http.agent=Mozilla/4.0" argument in the java command line. If we want to do it in pure java code, the below is a sample code. Note, the response http headers are included in the returning string.

Writing Good Interfaces

CurtainDog — Fri, 24 Aug 2007 03:14:38 PDT

Here is a brief summary of why interfaces rock, and the characteristics of good interfaces.

Multiple Return Type

Just_Him — Thu, 23 Aug 2007 22:33:23 PDT

In the signature declaration we can have only one return type like public return_type functionName()

New Event-Driven Interprocess Communications

cantelo — Thu, 23 Aug 2007 16:48:04 PDT

This article shows a new way to communicate Java with command-line processes. Instead of using the current Java API for interprocess communication, this article presents a new API named Jiipco! (http://sourceforge.net/projects/jiipco), that can be used to generate events from stdout and stderr output coming from a command-line process.

Working with Multipart Forms

efferus — Wed, 22 Aug 2007 00:57:01 PDT

Uploading and posting files using the Apache Commons Fileupload and the HttpPoster.

Colored Jtextarea

artemb — Tue, 21 Aug 2007 09:13:23 PDT

Set the background of a text area to a different color, and you can also paint on the text area.

Hiding The Mouse Cursor

artemb — Tue, 21 Aug 2007 08:33:25 PDT

How to hide the mouse cursor in your program.

Posting a Form with Java Code

Nistelrooy — Fri, 17 Aug 2007 06:45:26 PDT

We generally post forms with html. Here is a code sample that explains how to post a form with Java code.

Text Email to HTML Converter

mad.javaist — Thu, 16 Aug 2007 19:06:21 PDT

The code sample converts text email body into nicely formatted HTML, which can be directly sent to JTextPane for display. Uses mostly regular expressions replacements. Does this: - color codes replied portions marked with >, depth up to 6 - makes hyperlinks from email addresses and weblinks (a bit flaky on weblinks though) - converts _xxx_ into underscores, *xxx* into bolds - 'original message' headers and tabbed text converted to neat tables

Set fface="monospaced", fsize="3", htmltm should contain your text email.

Do We Allow Multiple Inheritance in Java?

The_Developer — Tue, 14 Aug 2007 03:43:01 PDT

Multiple Inheritance

Adding a Second IP Address

praveeng_cet — Tue, 14 Aug 2007 00:35:40 PDT

How to add a second IP address to your network card.

Contract Problem: Absence of Throws Exception in EventListener Method - ActionPerformed()

ljubad — Mon, 13 Aug 2007 05:02:24 PDT

Did you recognize that actionPerformed method from EventListener interface doesn't throw any Exception?

If you implement this method with public void actionListener(ActionEvent event) throws Exception, you would break the interface contract of the parent class.

To solve this problem you might make ActionListenerAdapter whitch throws Exceptions.

How to Upload Files Using JavaServer Pages

Jamwa — Mon, 13 Aug 2007 03:30:15 PDT

This is a simple JSP page that can upload files to a specified folder in the server. There is a Windows and a Linux version, though the procedures involved are more or less the same. The Windows version was tested on a Microsoft Windows 2000 Professional system whereas the Linux companion was done on Red Hat 9.0. The web server of service was Apache Tomcat 5.5 in both cases.

Recursive Function

ProcessQ — Fri, 10 Aug 2007 06:55:42 PDT

Hello all, I wrote a simple recursive function to traverse a directory, listing all files and folders. I wish if someone can give me a better solution to the same sample code provided, using multi threading concept. Currently the sample code takes a lot of time to traverse the root directory. WARNING!!! If you have a slow computer and you are traversing a large set of directories then the application may hang. Use and run the code at your risk.

Calling Main() Method of Another Class

Nistelrooy — Fri, 10 Aug 2007 03:56:26 PDT

This tip tells you how to call the main method of another class.

Object Cloning makes a Shallow Copy and not Deep Copy: Be Careful

Nistelrooy — Fri, 10 Aug 2007 01:30:36 PDT

Clone an object using java.lang.Cloneable.clone() makes a shallow copy and not a deep copy of the object being cloned. This tech tip explains the difference between the two.

Blinking Keyboard

artemb — Thu, 9 Aug 2007 10:17:04 PDT

Show how to blink the keyboard lights.

JButton Icon Changer

artemb — Thu, 9 Aug 2007 08:36:41 PDT

Change the icon on a Jbutton with every click.

No Need for Accessors and Mutators

1cMas5_cow — Wed, 8 Aug 2007 19:19:53 PDT

Here is a simple way to not need accessors and mutator methods in your code.

Writing Less Code When Using If()

1cMas5_cow — Wed, 8 Aug 2007 16:19:21 PDT

This is an easy way to write less code when using if then statements.

Reusable Method To Draw Image On a JPanel

1cMas5_cow — Wed, 8 Aug 2007 15:52:08 PDT

This method lets you draw images on a panel by simply supplying the Image and a Graphics.

Problems with ArrayList: Be Careful

Nistelrooy — Wed, 8 Aug 2007 06:50:45 PDT

ArrayList is simple and most frequently used but can give a serious performance blow.

Enter Text In To A Site's Texbox

artemb — Tue, 7 Aug 2007 10:36:06 PDT

How to enter text on a web page through java

7 Times Faster Replacing Than String Class's Replace() Method

Nistelrooy — Tue, 7 Aug 2007 00:02:13 PDT

This article gives a faster option of String replacing over String class's replace() method.

Desktop Event Alerter

Jamwa — Mon, 6 Aug 2007 04:54:31 PDT

A simple sliding effect desktop event alerter. Uses JWindow and threads to give the sliding effect.

Tool Support

P.G.Patrudu — Sat, 4 Aug 2007 04:31:28 PDT

Abstract : Tool vendors are often required to implement several interfaces on objects. Typically the modules of the tool would invoke these interface methods during execution. If objects were to implement all the interfaces required by these tools, then the application code could get submerged in the tools implementation logic. This article explains the widely prevalent solution and attempts to extend it to cover new frontiers.

Framework For a Unit Class For a Java RTS

1cMas5_cow — Thu, 2 Aug 2007 14:48:20 PDT

This class will help you in writing an RTS by allowing you to create one class to handle all your units and structures. This class is a basic framework for this job.

Math Library

artemb — Thu, 2 Aug 2007 06:58:23 PDT

Did you ever need an advanced math library for your program, but can't write one and don't know which to use. You can use the Apache Math Library.

Code to Simplify Random Number Generation

1cMas5_cow — Wed, 1 Aug 2007 14:14:56 PDT

A reusable method to simply create random numbers when needed.

Important Note When Using Paint() or PaintComponent()

1cMas5_cow — Wed, 1 Aug 2007 14:09:34 PDT

An important thing to note when using a paint() method.

Types of Games

artemb — Wed, 1 Aug 2007 06:40:26 PDT

Describes the different types of games that can be written in Java.

Limit Textbox

artemb — Tue, 31 Jul 2007 16:26:28 PDT

Limit the amount of chars entered into a text field.

Change Text Color in a Game for Flashing

1cMas5_cow — Tue, 31 Jul 2007 15:00:09 PDT

This code will make a color changing text with 4 colors. It is easily extended.

Framework For An Application Timer

1cMas5_cow — Tue, 31 Jul 2007 14:37:34 PDT

This is a simple framework for a timer in Java.

Mills To Time

artemb — Tue, 31 Jul 2007 11:58:41 PDT

Convert the System.currentTimeMillis() to time.

Constructor

artemb — Tue, 31 Jul 2007 10:40:16 PDT

This code sample shows how to call a different constructor of the same class.

Key Writer

artemb — Tue, 31 Jul 2007 10:20:15 PDT

Writes the users key presses to a file, for your application.

Draw Grid

artemb — Tue, 31 Jul 2007 08:58:32 PDT

Code to draw a custom grid.

Decimal Counter

artemb — Tue, 31 Jul 2007 08:04:40 PDT

A simple class that counts the number of places after the decimal.

Link Counter

artemb — Tue, 31 Jul 2007 07:52:57 PDT

Counts the link on the page.

Reading from Unknown Length InputStream and Storing Read Data into Byte Array

.@_ — Tue, 31 Jul 2007 05:15:27 PDT

The read(byte[]) method of InputStream requires the length of inputstream data to be known. So here is the solution for storing the data read from unknown length input stream into a Byte Array.

Easier Way to Track Mouse in Custom Components

1cMas5_cow — Tue, 31 Jul 2007 00:30:21 PDT

This technique can be used to track the mouse's position for collision testing of the mouse, among other things. It can even be used to draw rough custom cursors or to help do event handling in custom buttons, if you write a custom GDI.

Find String Permutations - excellent program

upnishad — Mon, 30 Jul 2007 23:33:09 PDT

I found an excellent way to find the String Permutations using a recursive function call.

Beginnings of a Java Shell

1cMas5_cow — Mon, 30 Jul 2007 21:45:59 PDT

This code can be used as the framework for a Java shell.

Custom Layout

artemb — Mon, 30 Jul 2007 19:45:06 PDT

An easy way to create a custom layout.

Tool to Search Wikipedia With Firefox

1cMas5_cow — Sat, 28 Jul 2007 18:23:18 PDT

This GUI will take any query you give it and open the Wikipedia page it finds in Firefox.

Easy Code to Type in Letters From a String

1cMas5_cow — Sat, 28 Jul 2007 11:05:59 PDT

If you ever had a program that needed to type in letters into a text field then this code will do it. It accepts a character array of lowercase letters and numbers. It has different delays for each key to keep it life like.

Configuring Java on Linux

1cMas5_cow — Sat, 28 Jul 2007 10:48:14 PDT

A simple guide to setting up a fully functional Java installation when then official instructions end.

The Need For A Plan

1cMas5_cow — Sat, 28 Jul 2007 10:25:59 PDT

A short tech tip about how to improve application performance through better planning.

Storing and Accessing Objects Programmatically

stevehaggaipersonal — Fri, 27 Jul 2007 11:03:16 PDT

Here is a brief description on how to store objects dynamically. There are certain times when the coder does not know the number of objects or data in advance. It is for such situations that I am writing this tech tip.

Simple Numeric Only Text Field

elisha.ebenezer — Thu, 26 Jul 2007 23:36:27 PDT

A simple code snippet on making a JTextField to accept only numbers.

What NOT To Do When You Use Robot To Move Cursor

1cMas5_cow — Thu, 26 Jul 2007 18:09:53 PDT

I was writing some code to make the cursor bounce on the desktop, but I couldn't get cursor control back. So here is what I learned.

A Very Simple Way to Skip Part of Code Without Using Comment Symbols

.@_ — Thu, 26 Jul 2007 13:55:35 PDT

Cool way to skip part of a code while testing a method without using // or /* */ comment symbols.

Aetas: Simple Tool & Eye Candy GUI

ashishlijhara — Thu, 26 Jul 2007 12:38:21 PDT

Aetas (Latin word for time) is a simple application with eye candy GUI and animation.

Printing Classes

DataVirtue — Thu, 26 Jul 2007 11:45:42 PDT

A set of classes to ease your printing troubles in Java. Mostly for newbies distraught with the highly configurable yet difficult printing model. These classes can be easily modified to print more than text. Also included is a class to easily generate labels with iText.

Integrating Simian with ANT to Find Code Duplication

Arvind — Thu, 26 Jul 2007 06:40:51 PDT

Integrating simian framework with project ant build enables developers to find code duplications. Code duplication(s) are extremely difficult when you are involved in large project with different development approaches.

The Real Difference: == and equals()

Nistelrooy — Thu, 26 Jul 2007 04:47:45 PDT

Generally people get confused while making String Comparisons with == and equals(). This tech tip explains how it really is.

Few Garbage Collection Myths: All Wrong

Nistelrooy — Thu, 26 Jul 2007 04:35:19 PDT

There are few widespread myths about garbage collection that sometimes add fuel to the fire.

Moving from Linux to Solaris

1cMas5_cow — Wed, 25 Jul 2007 08:50:21 PDT

I tried the free Solaris 10 DVD, and have written this guide to easily transitioning from Linux to Solaris.

Overriding the Maximized Bounds of a JFrame

vicsstar — Wed, 25 Jul 2007 07:13:15 PDT

This example shows the use of the setMaximizedBounds() method to override the behavior of a frame in terms of its location and size when maximized by specifying the maximized bounds of the frame, irrespective of the default location and size of the frame.

A Simple and Flexible Encryption

1cMas5_cow — Wed, 25 Jul 2007 06:33:18 PDT

A simple and customizable Java source file that can be built right into your application without any understanding of Java cryptography and using only built in Java components (by that i mean only stuff that ships with Java 1.6.0 Update 2).

Watching the Sun with Java

1cMas5_cow — Wed, 25 Jul 2007 05:58:09 PDT

Have you ever wanted to build a program to check on the SOHO mission any time? In this article, I'll take you step by step using NetBeans IDE and the Internet to achieve this goal.

Create a Confusing Secret Code

1cMas5_cow — Wed, 25 Jul 2007 05:35:26 PDT

This is a flexible and simple way of encrypting and decrypting. This is an encryption/decryption file I wrote called y2k.java. I wrote it because integrating strong codes like blowfish into Java is very difficult. I tried to, but couldn't get blowfish to integrate with my application. So I developed this unique code. Change it at will. I publish my software under GNU v.2!

Using Java Crypto APIs for Encryption & Decryption

smahmoud@gmail.com — Wed, 25 Jul 2007 04:19:52 PDT

This class includes two reusable functions for encrypting byte array using single/triple DES and for decrypting an encrypted byte array.

For myself, I used it to encrypt ATM card PIN number before sending it to HSM for PIN verification.

Know Location of Class File in Application

PanKaJ — Tue, 24 Jul 2007 13:19:15 PDT

Code to check which Java class from the current classpath is being used by your application.

Easy Way to Change Screens in Java Based Games

1cMas5_cow — Sat, 21 Jul 2007 10:37:06 PDT

Using a feature I developed when I played around with java game development, you can easily switch from ANY point in the game, be it game play, menu, about page, you name it. All this is controlled by a single integer.

Removing Stateful Session Bean

makkar — Fri, 20 Jul 2007 13:32:58 PDT

Removing Stateful Session Beans is important to avoid the need for passivation, minimize container overhead, and provide better performance.

Isolating Javascript Event Handling

VJ108 — Wed, 18 Jul 2007 20:11:24 PDT

A short tip on isolating event handling for your controls.

The Management Package (java.lang.Management)

RahulSharna — Fri, 13 Jul 2007 06:24:08 PDT

The below content describes usage of the set of APIs provided with Java Devolopment Environment in order to Manage & Monitor Current Java Platform.

Mechanism and System for Representing and Processing Rules

P.G.Patrudu — Fri, 13 Jul 2007 05:49:26 PDT

Abstract : The aim of any language is to provide means for representing/describing ideas and concepts. Programming languages are no exception to this norm. The core of conceptualization revolves around, finding the minimum set of notions, which could describe, all programming scenarios. Determining the minimum set of notions, for a generalized scenario, is a tall order, but is much sought, by the programming community. The following is an endeavor, which provides basis, for the minimum set of notions, in terms of an extendable framework.

Where On Earth Does NetBeans Keep It's Library Manager Records

Jeveloper — Wed, 11 Jul 2007 11:04:26 PDT

IDEs have their own little world within our system (OS) and the more advanced they are, the harder it is to migrate them to a e.g. new computer with existing IDE (same one) but moving plugins, libraries, etc. proved to be far from easy.

Small But Handy InitCap Method

Jeveloper — Wed, 11 Jul 2007 11:03:00 PDT

I had a need to initialize the first letter e.g. SERGE would become Serge hence i wrote this method that you can use freely.

Everyone who uses Oracle knows the initcap() is a handy function.

A Common JDBC Pitfall

namespace1 — Wed, 11 Jul 2007 05:11:09 PDT

Fact: When you get a JDBC connection, you use it to create prepared statements, callable statements, and ResultSets.

Use List Of Beans To Display On JSP

seetaramRao — Wed, 11 Jul 2007 05:07:26 PDT

It is easy to use list of beans to display the beans on JSP.

The Enhanced For Loop (for-each loop)

sri-duke — Tue, 10 Jul 2007 22:22:34 PDT

An easy way of iterating through an array or a Collection.

A Brief Set of Constructor Rules

filestream — Tue, 10 Jul 2007 12:12:44 PDT

Herein are some rules regarding constructors.

Final Variable

siva_20081976 — Tue, 10 Jul 2007 10:43:34 PDT

class level final variable must be intialized whether used or not method level final variable need not be initialized if not used

Performance impact with trycatch and if condition

PanKaJ — Thu, 5 Jul 2007 03:23:50 PDT

its better to use if condition if you are not sure about value being test is null or not. But if you are sure that 99% of time, value being tested is not null, then you should go for try-catch block.

Careful while using parenthesis

pandian — Tue, 3 Jul 2007 05:42:38 PDT

This code sample tells that brackets should not be used in all places. Careful analysis should be done before using brackets or else it will lead to mistakes like the one in this program.

An important tip for BufferedOutputStreams

sri-duke — Mon, 2 Jul 2007 22:32:23 PDT

Don't forget to call flush() on the BufferedOutputStream after you finish writing a file.

Tag files to encapsulate and reuse html.

lacroix1547 — Fri, 29 Jun 2007 19:09:01 PDT

How cool are tag files. It is a great standard/ideSupported way to encapsulate and reuse html. Those things are not only important for fully equiped programming languages. Look at this tag-file revamp of a classic example.

A simple and efficient way to browse all files in a directory and its sub-directories.

sri-duke — Fri, 29 Jun 2007 00:17:52 PDT

This technical tip defines a powerful way to browse all files in a particular folder and its sub-folders, and do some tasks on each file.

Singleton Using Double Checked Locking

elisha.ebenezer — Thu, 28 Jun 2007 01:39:53 PDT

How to ensure that one and ONLY one instance would be created while trying to make a singleton.

Elements Ordering In Priority Queue

padma.asrani — Wed, 27 Jun 2007 10:22:12 PDT

A tip on how to Traverse elements within Priority Queue in order.

Generate toString()

rushitpatel — Wed, 27 Jun 2007 07:58:05 PDT

toString() provides a simple, convenient mechanism for debugging classes during development, by translating object state into text. But toString() is very tedious to code as an off if any field get updated , we need to update toString(), so I had written a method which will take class as input and generate toString() using reflection .

StringBuffer or StringBuilder

henry_martin — Wed, 27 Jun 2007 07:41:11 PDT

Here's a tip on when to use StringBuffer and when to use StringBuilder.

Easy Tip to Center a JFrame on the Screen

sri-duke — Wed, 27 Jun 2007 01:12:00 PDT

A simple way to avoid displaying a JFrame at the top-right corner of the screen.

How To Monitor Every Copy On Windows

arjenve — Tue, 26 Jun 2007 23:59:08 PDT

In this text I will explain how to see every text copied to the system clipboard without using polling or an external library. To implement the code I read the source-code of the jdk that is now available on openjdk.net.

How To Insert Photo Into Database

JustPratik2107 — Tue, 26 Jun 2007 23:13:08 PDT

Enter photo into database

How To Get Parameter Meta Data From JDBC

JustPratik2107 — Tue, 26 Jun 2007 23:10:03 PDT

Below is to get parameter data from JDBC

How To Get Attachment File Name

JustPratik2107 — Tue, 26 Jun 2007 23:08:03 PDT

How to get attachment file name.

Autoboxing: The Basics

MangoDwarf — Sun, 24 Jun 2007 17:42:22 PDT

Autoboxing is a newly added feature as of Java 5 and is intended to make a Java programmer's life easier by allowing the implicit wrapping and unwrapping of a primitive within a wrapper object.

This article provides a behind-the-scenes look at autoboxing at its basic level.

Making images in a jsp page

biojae — Sat, 23 Jun 2007 17:11:13 PDT

creating an image in a jsp page is simple

PROGRAM FOR LOGIN FORM

datatycoon — Thu, 21 Jun 2007 11:08:40 PDT

sample login form using jlabel

Boolean object creation performance

PanKaJ — Thu, 21 Jun 2007 10:43:15 PDT

Improve performance when creating Boolean class objects

Loading a webpage

biojae — Wed, 20 Jun 2007 17:50:55 PDT

How to load a web page for parsing or other tasks

FloatingButton

artemb — Wed, 20 Jun 2007 15:46:20 PDT

Cool floating button click it to make it disappear. You think its so easy let's see you try it

How to OOP with a card game

artemb — Wed, 20 Jun 2007 07:59:35 PDT

How to break up your program in to logical objects, card game is used as an example.

An important difference between two classes

KeDeSol — Wed, 20 Jun 2007 06:08:30 PDT

Difference between ClassNotFoundException and NoClassDefFoundError

Getting Square Root of BigDecimal

ag2uki@yahoo.co.uk — Wed, 20 Jun 2007 03:31:56 PDT

How to find the correctly rounded positive square root of a BigDecimal value.

Overriding the equals method

pluff — Wed, 20 Jun 2007 00:36:06 PDT

This article is about the common mistakes one can make using and overriding the equals method.

Convert Binary to Decimal Swing Demo

Shahid_Raza — Tue, 19 Jun 2007 21:05:08 PDT

This program will accept the binary number and convert and display corresponding decimal number in textfield after pressing button change. If user enters any wrong binary number, it prompts a message box as an invalid binary number.

A cool tip on equals method when working with StringBuilder/StringBuffer/String class Objects

padma.asrani — Tue, 19 Jun 2007 13:19:17 PDT

Avoiding possible false values when comparing StringBuffer StringBuilder or String Objects using equals method

Varying Class file size with IF conditions

PanKaJ — Tue, 19 Jun 2007 11:55:18 PDT

In Java, IF condition can do trick in generated bytecode for class file.

Assigning a matrix element to a zero rank variable

Tsangpo — Tue, 19 Jun 2007 10:45:01 PDT

Extracts a value stored in a matrix so that it can be used with zero rank variables (non-matrices). This function is a user friendly front-end to DOT_PRODUCT() intrinsic function.

USAGE: VARIABLE = EX(MATRIX, INDEX)

Send multiple ESMTP mails simultaneously

deargopinath — Tue, 19 Jun 2007 09:18:37 PDT

This is an extract from Java Application built using NetBeans. It uses the concept of 'Multithreading' to send certain number of e-mails with a specific attachment to multiple respondents simultaneously.

This application can be used to test perfromance of * ESMTP Server * ESMTP filtering on Firewall

Split a String to perform search by words and search by cuotes ( " )

SCJD-Gabriel — Tue, 19 Jun 2007 08:21:08 PDT

This code separates your words using a white space as a delimiter, and also group a set of words inside of doble coutes ( " )

Convert a wilcard expression to a regex

Alpha.23 — Tue, 19 Jun 2007 07:22:54 PDT

Simple how-to on how to convert a wildcard expression to a regex.

Close a Dialog if the ESC Key is typed (Java 1.4+)

D.Wieser — Tue, 19 Jun 2007 06:06:57 PDT

Utility class used to close a dialog if the ESC Key is pressed. If a dialog or one of it's child components has the focus and the ESC Key is pressed then a "window is closing" event is dispatched to the dialog.

@Override and static method overriding

Narendra_Das — Mon, 18 Jun 2007 06:13:54 PDT

If a method marked with @Override fails to correctly override a method in one of its superclasses, the compiler should generate an error .But Why it is not giving?

Power of @Override in Java

Narendra_Das — Mon, 18 Jun 2007 04:42:20 PDT

This is showing the power of @Override in java5

Formatted text in your JOptionPanes

pmuurray@bigpond.com — Sat, 16 Jun 2007 21:10:28 PDT

Combine HTML and JOptionPanes for visual impact.

round gauge widget built from Swing components

larryfulkerson — Fri, 15 Jun 2007 23:14:07 PDT

This is a simple round gauge you could use as a progress monitor that I built from Swing components

Old NASA style counter widget

larryfulkerson — Fri, 15 Jun 2007 12:36:08 PDT

An old style NASA style counter widget built from Swing Components

A Sample File Uploader

Narendra_Das — Fri, 15 Jun 2007 05:02:09 PDT

Here is the Code Sample for Socket based File Uploader that can be used for file uploading purpose.I had tested the application for .pdf,.doc,and .jpg files .Those file types are successfully uploaded and open in their respective applications.

For testing this application follow the steps.

1.run UploadServer first.

2.run Uplodder next.

3.You have to edit the File names with their respctive path inside the code.I had tried it in a windows based machine.

a moving graph widget built using Swing components

larryfulkerson — Fri, 15 Jun 2007 00:24:05 PDT

This is a moving graph widget built using Swing components

An Ammeter widget build from Swing components

larryfulkerson — Thu, 14 Jun 2007 21:03:30 PDT

A working ammeter sort of widget built from swing components

New Way to Specify Bit-Ness with Sun Studio 12 Compilers

richard_friedman — Fri, 8 Jun 2007 15:46:59 PDT

The Sun Studio 12 compilers now us the -m64 flag to invoke compilation of 64-bit objects

How To Download Files With Authentication

Jean_Paul_1986 — Fri, 8 Jun 2007 14:52:01 PDT

Hello everyone. This is a program I wrote similar to the other one that downloads files with user name and password authentication.

How To Download Files In Java

Jean_Paul_1986 — Fri, 8 Jun 2007 14:38:59 PDT

Hello everyone. This is a simple file downloader I wrote some time ago, I would like to share it. :D

Visual Regex Tool

TuringPest — Fri, 8 Jun 2007 12:11:07 PDT

A Visual Tool for Creating Regular Expressions

Using JSTL in your own custom tags

mkoryak — Fri, 8 Jun 2007 11:26:01 PDT

This code will allow you to use JSLT expressions for you custom tags, so you can pass a paramter like this param="${some.crazy.deeply.nested.thing}"

in this example i expect a Date object from the expression, change as needed, and put into Tag

(stolen from my own blog at: http://notetodogself.blogspot.com/2007/03/using-el-in-custom-tags-as-attributes.html )

An Easy Way To Change The Look And Feel Of Any GUI

Jean_Paul_1986 — Thu, 7 Jun 2007 18:03:27 PDT

Hi everyone... This is another of my favourite classes. I wrote it a lot of time ago and I use it to change the look and feel of my applications on an easy and fast way.

A Class To Make Queries To The Windows Registry

Jean_Paul_1986 — Thu, 7 Jun 2007 15:31:12 PDT

Hi,,, this is a class I wrote some time ago to be able to identify some of the hardware characteristics of the local machine using java.

Avoiding JDBC catastrophe: Properly close your JDBC resources

cotton.m — Thu, 7 Jun 2007 09:31:51 PDT

This article looks at why closing JDBC related resources properly is important and what "closing properly" actually means.

Identifying the client side JRE Vendor and Version

maple_shaft — Thu, 7 Jun 2007 07:23:26 PDT

If your JSP or HTML page needs to be aware of what JRE vendor and version is running on the client side, then this nifty little detection applet mixed with some clever JavaScript will provide that information to you.

apply SSL on Sockets

eaaje — Thu, 7 Jun 2007 05:03:53 PDT

simple example for SSL on Sockets

Sending emails through java

will-code-for-food — Thu, 7 Jun 2007 00:46:48 PDT

Uses Java Mail API.

Story behind int and Integer in polymorphism

qUesT_foR_knOwLeDge — Wed, 6 Jun 2007 15:46:35 PDT

Before reading this have a look at this. There is a link between the post in this link http://www.sdnshare.com/view.jsp?id=532 and the post which I an making below.

Difference between int and Integer in Polymorphism

qUesT_foR_knOwLeDge — Wed, 6 Jun 2007 14:55:13 PDT

Here is some phenomenon, when it comes to polymorphism. Run the code and have a look at the ouput. Compare the output with the output that you otherwise expected.

Reflective method binding

YAT_Archivist — Wed, 6 Jun 2007 14:37:06 PDT

Class.getMethod is limited in that it only returns methods with the exact argument types you specify. The JLS defines the way in which method invocations are bound, and this code replicates that algorithm to a fair degree. It's an updated version of 1.4 code, so has no support for variable arity or autoboxing. For some purposes it may be appropriate to remove UnconstructableMethodException and just return the method anyway.

Unique String code generation

gdupont — Wed, 6 Jun 2007 13:59:39 PDT

This class allow to generate a unique code as a String or an int for a String object using a specified algorithm. I tried to optimize the "KeyMaker" (where does it come from ?) using a pool of Keymaker (one for each algorithm used) and a kind of cache. I don't know if it is really optimized at all (since the cache has no limit...) but it has been useful in one of my program.

I did not provide any test (I should have made JUnit), but the call if really simple through the public static methods and it appears to work well for my application.

Comparing date at a specified scale

gdupont — Wed, 6 Jun 2007 13:15:30 PDT

This class was dedicated to a simple task : comparing two different and providing the difference in accordance to a time scale. For example, instead of saying that between 2007/06/04 and 2007/06/06 their is 1234.... milllisecs, it can say their is 2 days or 48 hours, depending on the scale you choose. I provide the class and a simple JUnit which only test the correct behavior with known dates.

Commands for Sun Studio 12 Compilers and Tools

richard_friedman — Wed, 6 Jun 2007 12:31:19 PDT

A list of the Sun Studio command-line tools, organized by functionality, with links to their man pages.

The Omniscient Universal Answer Machine

TuringPest — Wed, 6 Jun 2007 11:14:27 PDT

Get the Answer to ANY Conceivable Question From this Program

Connection Pool

filestream — Wed, 6 Jun 2007 08:11:04 PDT

A connection pool

PreparedStatements: Basic usage examples and why they are important.

cotton.m — Wed, 6 Jun 2007 08:06:30 PDT

This article looks at the three reasons you should be using PreparedStatement in your code vs. Statement: portability, security and performance.

Deploying Java Applets With Family JRE Versions in Java Plug-in for Internet Explorer

maple_shaft — Wed, 6 Jun 2007 06:33:15 PDT

JRE Family Versioning can be a good solution to verify that your applets will only be run against a specific JRE Family.

Store Object into Byte Array

Deepak-Bhatia — Wed, 6 Jun 2007 06:20:04 PDT

This tech tip shows how to store java object into byte array.

Defensive Copying

YoGee — Wed, 6 Jun 2007 05:35:33 PDT

An introduction to defensive copying.

Analyzing dependencies

kajbj — Wed, 6 Jun 2007 04:04:41 PDT

There are lots of code samples and libraries that try to solve dependencies. Many of them do not list dependencies to classes that are referenced by local variables or annotations. This is a fairly simple example that uses ASM (a bytecode manipulation framework) to resolve dependencies. ASM is similar to BCEL, but it's faster and smaller.

The example (that doesn't try to find dependencies caused by reflection) uses ASM 3.0, so you need to download it first.

JPA Hibernate class path

fagossa@gmail.com — Tue, 5 Jun 2007 15:42:12 PDT

libraries required to make Hibernate JPA actually works

Replace "." using regexp

kajbj — Tue, 5 Jun 2007 13:20:35 PDT

Many beginners have problems when they are trying to replace a dot using regexp.

Using Reflection to Get Private Array Lengths

TuringPest — Tue, 5 Jun 2007 12:40:48 PDT

General Purpose Code to Retrieve the Length of a Private Array

MultiMap - a map from keys to sets of values

YAT_Archivist — Tue, 5 Jun 2007 12:27:11 PDT

An analogue to map which supports multiple mappings for a single key. (Mathematically this is a relation).

A JPanel that stands out

filestream — Tue, 5 Jun 2007 12:22:21 PDT

A JPanel that stands out from the crowd. Ever have the need for a JPanel that stands out from the rest of your GUI? Well, use this JPanel. It has borders that makes it visually appealing. I use it in BorderLayout.SOUTH of my JFrame. Try it yourself and watch your boss give you that raise your deserved last year.

RadioButtons in a JTable Cell

sriprasad — Tue, 5 Jun 2007 12:15:30 PDT

Add JRadioButton to a table Cell.

Associating JARs with J9 in Windows Mobile

YAT_Archivist — Tue, 5 Jun 2007 12:15:14 PDT

How to associate .jar files with J9 in Windows Mobile.

Regression by least squares

YAT_Archivist — Tue, 5 Jun 2007 12:06:41 PDT

This class provides immediate support for polynomial regression of a data set, with the option of forcing the polynomial through the origin, and also a framework to build regression methods which find weights for arbitrary independent basis functions.

There is one dependency, on Jama, a linear algebra package available from NIST.

Please forgive the inevitable mangling of the Javadoc, but there's no documentation that I can see telling me what forms of escape are supported, and this is my first submission to the SDN Share.

Minimize a JFrame to SystemTray

Dalzhim — Tue, 5 Jun 2007 10:57:11 PDT

When enabling the usage of the System Tray for an application, the most annoying part definitely is to make sure that an application will behave normally on platforms which do not have a System Tray!

This JFrameTray class (yes I know the name is pretty ugly) will minimize to the SystemTray according to the settings you are using (goes to tray when window is minimized or closed, or both, or none) using the TrayVisibilityMode you wish (Always visible, Never visible, Visible when JFrame isn't) on platforms which provide a SystemTray, and will use the defaultCloseOperation otherwise.

Unexpected Non-Polymorphism

CeciNEstPasUnProgrammeur — Tue, 5 Jun 2007 10:45:29 PDT

Sometimes, polymorphism and inheritance combined just won't work...

Getting an IP address range from a String and an int

cotton.m — Tue, 5 Jun 2007 08:51:07 PDT

Sometimes you need to calculate a range of IP's (a start and stop IP address) from a given address and an int representing the range. This code does this for IP4 addresses.

The enclosed sample includes a main for a simple demonstration.

A JTable With Alternating Row Colours

filestream — Tue, 5 Jun 2007 08:32:21 PDT

A JTable with alternating gray and white rows so that content is more readily distinguishable. Modify as you see fit. Your mileage may vary. Do not spindle, fold, or mutilate. This code should not be used by women who are pregnant, nursing, or may become pregnant.

Easy Printing for JDK 1.4 and Below

The_Developer — Mon, 4 Jun 2007 23:53:52 PDT

Do you find yourself stuck on how to print in Java? Losing sleep by trying to figure out how you can easily print in that JTextComponent of yours? Well your never ending search has now been answered. Below is the code that you can use for your application:

Simply use it like: new PrintMe().print(YourJTextComponent);

Sample Code to Parse XML: Generate Its Replica with Custom Values

chiragpatel_05 — Mon, 4 Jun 2007 00:51:25 PDT

It will parse your Source xml file, create its replica and allows you to put your values inside elements. e.g. Source File:

Result File:

Put your value Put your value

Display Images in Table Cell

pandian — Tue, 29 May 2007 07:48:39 PDT

This code sample tells how to display images in a cell. This code can also be used for other objects provided the rendering code is changed appropriately.

Improving Performance of Program

vijaykhambe — Tue, 29 May 2007 04:50:08 PDT

More simple program will run more efficiently.

Scope of Objects

ishkmi — Mon, 28 May 2007 00:15:32 PDT

Scope of the objects when developing web apps

Validate Date String

jbodnar — Sun, 27 May 2007 04:43:14 PDT

Validate Date String

How To Close Frame Window

Pathankotiaboy — Sat, 26 May 2007 03:18:08 PDT

This closes the frame when a user presses the close button.

SVG Document Java Event Listener

jbodnar — Fri, 25 May 2007 12:56:58 PDT

SVG Document Java Event Listener

Batik SVGCanvas

jbodnar — Fri, 25 May 2007 12:55:39 PDT

Display SVG Document args[0] URL

Timer Task

jbodnar — Fri, 25 May 2007 12:52:58 PDT

Timer Task

Caller Class Name

jbodnar — Fri, 25 May 2007 12:51:03 PDT

Get the Caller Class Name

JavaMail Send Message

jbodnar — Fri, 25 May 2007 12:49:09 PDT

Send mail.

Java Util Logger

jbodnar — Fri, 25 May 2007 12:47:20 PDT

Java Logger

POI ReadWrite XLS file

jbodnar — Fri, 25 May 2007 12:42:50 PDT

Read and Write XLS File with POI

Write Oracle BLOB Field

jbodnar — Fri, 25 May 2007 12:40:46 PDT

Write Oracle BLOB Field

DataSource getConnection

jbodnar — Fri, 25 May 2007 12:38:19 PDT

DataSource getConnection

XML Config File

jbodnar — Fri, 25 May 2007 12:32:33 PDT

/* * Read and Parse XML Config File : * * * * * * */

Call a Web Service

jbodnar — Fri, 25 May 2007 12:30:12 PDT

Call a Web Service

JMS Send Message

jbodnar — Fri, 25 May 2007 12:19:15 PDT

Lookup Queue Connection Factory and Destination Send a Message

Convert Decimal to Any Base

gurpreet_gh761230 — Fri, 25 May 2007 04:36:43 PDT

Convert decimal to any base.

Rounding Number Up to the Specified Decimal Places

vijaykhambe — Fri, 25 May 2007 01:44:33 PDT

Rounding number up to the specified decimal places

Handling Expressions Involving Different Type Variables In the Left and Right Side

Java-For-Everything — Thu, 24 May 2007 23:07:50 PDT

The method of type casting from integer to float or double.

Copy Files Faster

alzoid — Thu, 24 May 2007 04:34:20 PDT

Use the nio package to make copying files faster.

Difference Between Two Dates

gurpreet_gh761230 — Wed, 23 May 2007 01:21:33 PDT

To compute the difference between two dates in years, months and days

Installed Looks and Feels

larryfulkerson — Tue, 22 May 2007 22:48:45 PDT

To get a list of the currently installed looks and feels on your system.

Script to Move the Selected Value From One List Box to Another

ajju.krishna — Tue, 22 May 2007 01:41:17 PDT

This Script is used to move the selected value from one List Box to Another as well as Sorting both the List Boxes.

Convert Decimal to Binary Number

waruna2003 — Mon, 21 May 2007 22:50:23 PDT

Convert Decimal to Binary Number

Send SNMP Traps for Applications Using Log4j

waruna2003 — Mon, 21 May 2007 22:36:58 PDT

Send SNMP Traps for applications using log4j

Java Archived Serialization

Vasile-Alin — Mon, 21 May 2007 03:37:43 PDT

A possibility to serialize big classes in archived files, to save disk space.

Non-Volatile Directed Graph of Enums

pmuurray@bigpond.com — Sun, 20 May 2007 18:07:07 PDT

Here's a couple of classes I did last year. A class that holds a directed graph of an enum, and one that uses that graph.

Loading Resources from the CLASSPATH

dbush21 — Fri, 18 May 2007 14:02:19 PDT

Two convenient methods for loading a resource from the CLASSPATH.

String Comparison

babukesavan — Fri, 18 May 2007 13:06:31 PDT

How to compare string values

Deleting Blank Spaces in a String

Stendeck — Fri, 18 May 2007 12:32:48 PDT

Deleting blank spaces [ \t\n\x0B\f\r] into a String using StringUtils and Split.

Variable Number of Arguments

pandian — Fri, 18 May 2007 07:41:26 PDT

As in C and C++, Java too supports Variable arguments. C and C++ support them using va_arg and something like that, but java simply uses the concept of arrays. While using it in a method, it will be similar to C and C++ but the usage is exactly the same as an array. This variable argument is supported by both objects and primitive data types.

Generic Methods to Work with Enums, Using Intersection Types

pmuurray@bigpond.com — Thu, 17 May 2007 22:37:37 PDT

Intersection types - a new feature in the Java language - allow one to deal with generic enumeration types that implement a known interface. An example use of this is referencing enumerations by methods other than their name or ordinal.

Passing Huge Data from Servlet to Applet

anuj2ee — Thu, 17 May 2007 12:19:22 PDT

To show large amount of data in applet JTable

Autoboxing: Getting Confused

Keyboarder — Thu, 17 May 2007 02:24:36 PDT

Dynamic Tooltip For Form Fields

henry_martin — Thu, 17 May 2007 01:57:02 PDT

The following code sample can be used to generate dynamic tooltip i:e tooltip that shows dynamic data (data generated at runtime) by making use of a very compact javascript function.

Initializing Instance Variables in Class....

JavaDiablo — Tue, 15 May 2007 12:13:46 PDT

If you initialize the variable in the class where it is declared, it can potentially get changed from the value assigned inside the constructor.....i.e. if you declare and initialize it null, and in constructor assign it say "bad", it can potentially become null again when you try to use it... We once encountered this problem, can't really exactly remember which step caused it, but we changed out coding guidlines to never initialize it when you are declaring it.. instead just declare it..like String name; instead of doing String name=null;

Multi Line Label with HTML Tags

syncjava — Tue, 15 May 2007 02:43:58 PDT

HTML tags can be used to create multi line Jlabels, JDialogs.

Literal strings and equalsIgnoreCase method

bogolubs — Thu, 10 May 2007 13:34:54 PDT

Avoid a possible NPE when comparing literal string to String var

Use static analysis to improve your code

PeterHendriks — Wed, 9 May 2007 00:39:10 PDT

There are several tools available for Java that provide feedback on the quality of your code. This tech tip points to several popular analysis tools that will find errors and improvements in your code automatically.

Maven new technology POM (Project Object Model)

hirenaik — Wed, 9 May 2007 00:28:25 PDT

Maven is represented to maintain large build. Rather then going with Ant build utility this would be next gen. If you study ant you must have a look of this concept. You can find your local repository for maven after installation with windows machine "XP" C:\Documents and Settings\Administrator\.m2

OutOfMemoryError - Heapdump and Netbeans Profiler to the rescue

ktukker — Tue, 8 May 2007 23:58:42 PDT

You got an "OutOfMemoryError" and a killed application? Try creating a Heapdump file and anlyze it with Netbeans.

Start Java 5 server VM with Hibernate Linux

waruna2003 — Tue, 8 May 2007 03:57:54 PDT

Start Java 5 server VM with Hibernate

My Idea of implementation

chiragpatel_05 — Tue, 8 May 2007 02:28:47 PDT

A Sample method can give you some idea to set bean properties with the request parameter values.

Mt: Migration of Java Text Parsing Code Windows to Linux

SyedSaifuddin — Sat, 5 May 2007 02:00:32 PDT

Migration of java text parsing code Window to Linux

Sending Data From Server To Client (Simple Networking)

Java-For-Everything — Fri, 4 May 2007 22:21:41 PDT

The following set of two code samples one for the server and for the client. We can send any data from the server program to the client program. Execute these programs in two separate command prompts. Execute the server program in one cmd promt and then the client program in another. Now you can type any text in the server and press enter.. it will be displayed in the client cmd prompt.

You can learn the lastModified date of the files most clearly in your language

A-j — Fri, 4 May 2007 12:41:38 PDT

You can learn last modified dates of files in your language

You can learn the lastModified date of the files most clearly

A-j — Fri, 4 May 2007 12:05:19 PDT

There is a method for learning the dates of the files in java.io.File: file.lastModified (). But this method returns a number of miliiseconds since 1970. Do not you want to learn the dates of the files most clearly?

The Way We Can Color The Text in Swing Components

kirankumarr — Thu, 3 May 2007 07:19:26 PDT

Here's a way to color the Java text components using simple HTML tags, instead of using complex rendering and repainting methods.

GlassFish and Vista - Interoperable out-of-the-box

Arun@Sun — Fri, 13 Apr 2007 17:57:17 PDT

This tech tip explains how to write a trivial Web service that interoperates between GlassFish and .NET 3.0 framework.

Introduction to Ajax for Page Authors

x27zebra — Thu, 12 Apr 2007 17:34:40 PDT

Describes various techniques that page authors can use to add Ajax functionality to a web application.

Change OS Version Number for a particular shell

Rajadurai — Thu, 12 Apr 2007 17:15:56 PDT

In some cases program fail to run just because the version of the OS is not what it expects. Here is a simple DTrace script that will change the version of OS for a process and all its children and its progeny.

Here is how to run this program.

1. Copy the code into a file. 2. Change permissions. 3. run it with the pid of the process to fix. 4. Cntrl C to get back to normal.