Useless data types: Date, Date, Time, Timestamp

The Seven Habits of Highly Dysfunctional Design

Instead, someone at IBM came up with an idea of how to sabotage Java's simplicity: Donate the Taligent code to it! In a plan insidious enough to have been hatched by Larry Elison himself (if he weren't too busy going through Microsoft dumsters at the time), IBM got Sun to agree to put Taligent code into Java, thus ensuring that IBM Global Services would have ample work for the next ten years. It also ensured that the rational (no pun intended) Java developers would forever be taunted by the following license details in all Taligent-cursed code:

 * The original version of this source code and documentation is copyrighted
 * and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These
 * materials are provided under terms of a License Agreement between Taligent 
 * and Sun. This technology is protected by multiple US and International
 * patents. This notice and attribution to Taligent may not be removed.
 *   Taligent is a registered trademark of Taligent, Inc.

.... For more details... http://jroller.com/page/cpurdy?entry=the_seven_habits_of_highly

JSP: Avoid creating a session

To avoid creating session when a JSP is accessed add the following page directive in the JSP.

<%@ page session="false" %>

MDC NullPointerException in WSAD debug

I was using the Log4J 's MDC class to store some values in the Thread for logging.
When I started my WAS Test Environment server in debug mode...
I received a NullPointerException in java.lang.InheritableThreadLocal.java (69)
The Source code for this class says...

66| public Object get() {
67|     Thread ourThread = Thread.currentThread();
68|     Map map = ourThread.inheritableThreadLocals;
69|     Object value = map.get(key);

After searching on the internet found that this is actually a bug in the JRE of WSAD.
The way around for this problem is to disable the "hot method replace" functionality in WSAD.

Link: Apache Mail archive link