Using Range Paging in ADF – an example

Introduction: We recently had a requirement for loading large chunks on data from Oracle table into a background process using Java and ADF framework.  We were not allowed to use “straight” SQL and had to stick to ADF framework!  It took a little bit of time to understand how range paging worked – you see,…More

JDeveloper memory settings

Did you just get the “JDev is low on memory” error? or you have a beast of an application where you are trying to initialize a tree with a million or so nodes? (I was!) So .. first thought is, its gotta be some “config” file (because I did not start JDev as a jar…More

Boggle Solver

Attempt 1: Use Arrays and Lists and a recursive function to loop over all letters in the boggle board and find all possible words of size [min-length] to size [max-length] where min-length >= max-length. Code: Apr 16, 2010 2:42:59 PM 1 package boggle; 2 3 import java.util.ArrayList; 4 import java.util.Arrays; 5 import java.util.HashSet; 6 import…More

Why do OJC and Javac differ?

Introduction: A certain developer wanted to specify Generic Type in his abstract Java class, like the Java Map interface and AbstractMap class, in the manner described in Code Sample A, below. Setup: – We have 2 environments desktop and remote hosts – Applications are built on the desktop in JDEV (11gR1) using OJC by default…More

Python + MySQL in Ubuntu (9.10)

Assuming you did a fresh install of Karmic Koala – Ubuntu 9.10 Here are the steps: – Install Python: apt-get install python2.6 – Install XAMPP/LAMP stack: sudo tasksel install lamp-server After you install follow the steps on setting up the root password see the notes here . – Install MySQLdb: I tried downloading the sourceforge…More

Stuff to read

Must read up more on these – download, test, play JGraph – http://www.jgraph.com/mxgraph.html Parallel port interfacing made easy – http://www.epanorama.net/circuits/parallel_output.html Wireless Rabbit Web Server – http://killerprojects.wordpress.com/2010/04/06/wireless-rabbit-web-server-802-11-bg-w-video/#more-53 Introduction to WI-FI, Wireless LAN basics, Wireless Security, Rabbit Wireless doc – http://www.rabbit.com/documentation/docs/manuals/WiFi/Introduction/WiFiIntro.pdf Introduction to ZigBee – http://www.rabbit.com/documentation/docs/manuals/ZigBee/Introduction/ZigBeeIntro.pdf I Make Projects – Wireless Detector  (Hooking up a vibe motor…More

Design Patterns

Introduction  In the realm of enterprise application development, Java 2 Platform, Enterprise Edition (J2EE) has long stood as a bastion of robustness and scalability. An intriguing facet of J2EE is its harmonious blend with the timeless design patterns delineated by the Gang of Four (GoF). This post delves into how the GoF patterns breathe life…More

Matrix manipulation

When solving Boggle, Sudoku or some n-by-n board game or when doing Image analysis or Parallel Computing – it is often useful to be able to represent one-dimensional data structures in 2-dimension and vice-versa. Simple formulae exists for doing this conversion, as illustrated below: Converting from Row by Col 2-dimensional (2-index) format to a 1-by-(Row*Col)…More

Create tables in MySQL using JDev

Steps: Setup MySQL Setup JDev Create a new JDev Application Create a new Database Diagram with a sample Table Add columns to the table Create a database connection from JDev to MySQL and Publish the Table to MySQL Note:  Put the mysql-connector-java-3.1.14-bin.jar in the lib path (JDEV or JDK) to avoid Driver Not Found type…More