Blogs

Accessing local variables even after methods finish (in Java)

At times we write methods in Java classes with local variables that we need to access even after the methods finish execution. Here's an example:
 
public class FinalLocalVariableTest {
    public static void main(String[] args) {
        final int x = 5;

Java Programmatic Browser

At times you need to visit web sites, login, navigate through pages, select portions of HTML, click on links, check for the existence of a form, submit the form,.... and do all these things programmatically. So you need a programmable web browser that can execute and have a cup of tea while it will do the job.

Java programmatic browser

Apache Axis2 WS-Security message signing vulnerability (Version 1.5.1)

Note: See the bottom of this page to download the sample code used.

Rampart is the Apache Axis2 module that implements the WS-Security features. To add such features to your Web service, Axis2 provides two different configuration mechanisms. One depends on WS-SecurityPolicy and is the approach that is preferred. The other approach is known as the “parameter based configuration”.

Is MVC a design pattern or an architectural pattern?

MVC which stands for Model-View-Controller describes a software pattern that you can use in interactive computer systems. To understand if it is a design pattern or an architectural pattern, let's look at what these two are:

Architectural pattern: Concerned with the subsystems of an application with their relationships and collaborations with each other.

Design pattern: Concerned with the (further small) components of a subsystem with their relationships and collaborations with each other.

Configuring Genius G-Note 7100 in Linux

Recently I bought this device to draw online. Even though the internal storage device was auto detected when the USB cable was plugged in, the pen (or graphics tablet) function didn't work without installing the "wizardpen" driver.

Sample X.509 certificate collection with public/private keys (for Java)

If you want to test your Java application which requires digital certificates, here's a collection of such certificates with associated public/private keys in .jks format (the Java standard format - Java Key Store).

For example, you can use these to test Web services or enable SSL support of a Java server (and clients - if you want).

Java client connecting to an https resource via a proxy server that needs authentication

This doesn't look to be something trivial that you can simply do by passing the URL, proxy server host, port, user name and password to an already available class and getting the connection established.

Validating an XML document against a given XML Schema in Java

Many XML validators exist. Here's how you may implement an XML validator in Java. At times you may need to take a programmatic approach like this.

Poor man's telnet program

About 10 years ago I wanted to write a telnet client in PHP. My need was to login, execute some commands and logout. I was lazy to read the telnet protocol details. Hence I used the following approach to do it which worked for my purpose. Let your programming language be Java, C, C++, PHP, C# or anything else. It needs to have a TCP socket creation facility (TCP networking).

Here are the steps: