What did you learn today?

Database Connection Pooling

2009-01-20T22:06:00.000-08:00

Database connection pool is a collection/group of identical JDBC connections to a database. These connections are created when the connection pool is build or as and when a connection is required. The applications usually interact with some form of database and getting a connection from the application to fetch/update the data in the database, require some time which is unacceptable if we create

Core J2EE patterns: Business Delegate

2005-11-18T01:50:00.000-08:00

Context: The client does remote method invocation and is exposed to the complexity of the underlying business service implementationProblem1. Different clients need to access business services.2. The client is exposed to the implementation of the business service.3. If the service implementation is modified, the client is also affected.4. Unncessary network communcation (too many invocation

Pessimistic and optimistic locking

2005-10-11T07:19:00.000-07:00

Pessimistic and optimistic lockingThere are two different ways transactional locking is done. Pessimistic and optimistic locking and that is how transactional isolation is achieved.When we do pessimistic locking, we lock the resource when it is accessed the very first time and the lock is not released till the time, transaction is finished i.e, either committed or rolled back. The disadvantages

Spring framework

2005-10-10T09:32:00.000-07:00

These days I am reading the book. Spring: A Developer's notebook. A real fundu book. Just finished the basic understanding part and now reading how to implement MVC based on the spring framework.What surprises me is the ease with which you can write code with Spring. So simple, yet beautiful and powerful.

Spring and EJB

2005-10-10T04:41:00.000-07:00

Why Spring makes sense?1. Spring keeps the framework out of the code. i.e, no framework-specific requirements on objects.2. Spring is simpler than EJB mostly because they take a more POJO-based approach,3. Code is not heavily dependent on the container so unit testing is easy.You can even run some integration tests using a Spring container but not a heavier J2EE app server–unlike any app server,

JProxy

2005-03-29T23:11:00.000-08:00

JProxy is an J2EE HTTP tunnel with SSL and JAAS support for EJB, RMI, JNDI, JMS and CORBA. It was designed with the thought of creating a unified object model that lets you design your solution Internet without worrying about HTTP, Firewall drawbacks, implementation differences between different Application Servers, and integration between J2EE and CORBA standards. JProxy enables CORBA, JMS and

Easie and Myeclipse

2005-02-24T06:45:00.000-08:00

Note: If you are not able to see the pictures in this post clearly, I would suggest saving these pictures locally and then using any picture viewer tool to enlarge it. One of the projects I work on uses Easie welbogic plug-in. The development environment is already established and there is nothing much left there to experiment with. To understand it better, I thought about installing this plug-in

Introduction on JCoverage

2005-02-17T05:31:00.000-08:00

Hi!Today, I attended a small session on JCoverage. Not much in detail. But enuf to move forward. JCoverage lets you find out how much of your code is covered with your JUnit test test cases.In the example we worked on, we wrote some code and Junit test cases.Then we modified our ant build file. We defined another target 'instrument' like below:

Use of this and super key words

2005-02-12T01:26:00.000-08:00

Use of this and super key words-------------------------------------------------------------ConstructorsConstructors are special methods which are used for creating an instance of a class and initializing that instance.Consider the following example:/** Created on Feb 12, 2005**/package deepak.learn.twelve_feb_five;/*** @author Deepak.Saini**/public class ConstructorExample {int instanceVariable;

Java Logging API Basics

2005-02-11T08:22:00.000-08:00

Java Logging API Basics-----------------------------------------Java Logging API is part of Java 2 platform. It provides java.util.logging package which provides you with a logging facility with the following features-1. Embed messages inside your code2. configure at runtime whether messages should be displayed or not.3. If you decide to display the messages, you can configure what severity of

When to use PortableRemoteObject.narrow() and when to simply cast the reference?

2005-01-31T07:34:00.000-08:00

Most RPC protocols other than RMI can't take adventage of Java's code loading facilities (because they were not designed to work solely with Java). IIOP falls into this category. Therefore, when an IIOP stub is passed to a caller as a placeholder for a remote object, the IIOP protocol dictates that the actual returned proxy will be of the declared return type, not the actual run-time type of the