tag:blogger.com,1999:blog-51928825739531383612012-01-08T11:03:09.269-08:00Information about my everyday life with java language and java technologiesMikehttp://www.blogger.com/profile/05448370454151696512noreply@blogger.comBlogger91100tag:blogger.com,1999:blog-5192882573953138361.post-58409188480053419582008-08-03T09:05:00.000-07:002008-08-03T09:27:16.514-07:00

One of new features in Java 1.5 is direct support of enumeration using enum keyword. According to this the new method isEnum() has been added to java.lang.Class class (which is part of Java Reflections API). The problem is that the isEnum method doesn’t always behave as you would expect.Let’s start with the following Java code:public class MainTest { // Enum with custom constructor enum

Mikehttp://www.blogger.com/profile/05448370454151696512noreply@blogger.com1tag:blogger.com,1999:blog-5192882573953138361.post-76104326386821228852008-06-30T12:55:00.000-07:002008-06-30T13:22:55.855-07:00

State design pattern is extremely useful when you need a state class. Typical example is a class making a connection to a server (check POP3 client tutorial for example). The class then has two states – connected and disconnected (which is the default state). In the class you would need to check for the state at many places. Let’s imagine that your class doesn’t have just two states but four or

Mikehttp://www.blogger.com/profile/05448370454151696512noreply@blogger.com1tag:blogger.com,1999:blog-5192882573953138361.post-57456379562340611972008-06-08T06:11:00.000-07:002008-06-08T06:20:04.863-07:00

As you certainly know, one of the OOP’s features is encapsulation. Java has private keyword to specify encapsulated constructors, methods or attributes. These methods and attributes should not be accessible from the rest of the world (they are not part of the API) and Java doesn’t allow you to do that ordinarily.You can however use Java reflections API to access any private method, field or

Mikehttp://www.blogger.com/profile/05448370454151696512noreply@blogger.com0tag:blogger.com,1999:blog-5192882573953138361.post-43511134208744424262008-05-19T05:45:00.000-07:002008-05-19T12:08:12.022-07:00

A few days ago I started to take interest in JNI (http://en.wikipedia.org/wiki/Java_Native_Interface). JNI is used to call java native methods that are written in other language than Java. Java native methods are usually system dependent and are used to provide functionality that has to be handled by an operating system. Example is creating and handling threads in Java. This functionality is

Mikehttp://www.blogger.com/profile/05448370454151696512noreply@blogger.com2tag:blogger.com,1999:blog-5192882573953138361.post-7070187968192841662008-04-26T05:13:00.000-07:002008-07-04T09:54:46.651-07:00

Singleton falls into the group of simple design patterns. Singleton is a class that has one and only instance in an application. As singletons are usually realized pools (connection, thread, …), cash memories or drivers.Implementing singleton is quite simple task. The following steps have to be done:declare constructor as private to ensure that no instance of the class can be createdimplement

Mikehttp://www.blogger.com/profile/05448370454151696512noreply@blogger.com3tag:blogger.com,1999:blog-5192882573953138361.post-65576891533502347612008-03-24T11:09:00.000-07:002008-05-11T09:30:28.709-07:00

One of the new features in Java 6 is compiler API. It let’s you compile any Java source code file on the fly and after compilation you can load compiled class using a class loader and start using it. Because Java compiler doesn’t know anything about classes compiled on the fly, so you can use them only using java reflections.In the first step we need to prepare a class that is going to be

Mikehttp://www.blogger.com/profile/05448370454151696512noreply@blogger.com1tag:blogger.com,1999:blog-5192882573953138361.post-19152283664459583452008-03-11T13:34:00.000-07:002008-05-11T09:31:16.628-07:00

This article is intended for people who have no or very little experience with networking in Java.Today, my aim is to show you how to make your own simple POP3 client in Java. Some people are scared of creating a network application in Java because they think it have to be difficult to handle such topic, but opposite is true. It’s easier than you could think as you will see later. I chose the

Mikehttp://www.blogger.com/profile/05448370454151696512noreply@blogger.com2tag:blogger.com,1999:blog-5192882573953138361.post-66710882755731164732008-03-02T07:03:00.000-08:002008-05-11T09:31:44.995-07:00

A few days ago I came across an article about Groovy (http://groovy.codehaus.org). It took me so I decided to go through useful Groovy tutorial (you can find it here http://www.asert.com/pubs/Groovy/Groovy.pdf). Groovy is a scripting language based on Java. You can write your Java code in much simpler way using Groovy and you can whenever use legacy Java code in your Groovy code if you want to.

Mikehttp://www.blogger.com/profile/05448370454151696512noreply@blogger.com0tag:blogger.com,1999:blog-5192882573953138361.post-19516085224698036772008-02-24T10:52:00.000-08:002008-05-11T09:32:14.524-07:00

Java has simple API for working with date and time. Many people find the API deficient and I’m one of them. Although I was using SimpleDateFormat and GregorianCalendar classes in Java API for long time, sometimes I found it very cumbersome and unsuitable for my task. Sometimes there were problems with parsing input text and the problems couldn’t be directly solved using Java API. Java community

Mikehttp://www.blogger.com/profile/05448370454151696512noreply@blogger.com0