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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.