It's all about Java

 Java Classes and Objects: Classes and objects both are treated in similar way in all programming languages. Java is not exception. Understanding classes and objects with real world example Consider a physical class room with lot of real world objects. What we Observe in class room..? Chairs  Table  Students  Teacher  Black board Markers and Erasers etc So, a programmer needs to instruct the computer, how to create a class room object and it's subsequent objects. like, chair, table, teacher and student etc. If programmer wants to create or develop a School application, he would need to create: class room object Office room object, Student object, Stationary object Play room object etc Let us now create School application with above mentioned objects and classes using java programming language. To create Objects, first of all, we have to create respective classes in java public class School_Application{      public Student students;     ...

Immutable objects and mutable objects with an example  In object oriented programming language, in short OOPS, every problem, precisely every requirement is viewed as an object. Understanding the problem in this point of view brings many good things possible in programming like encapsulation, abstraction, polymorphism and inheritance. Anyways this post is not intended for describing benefits of OOPS. Object could be any thing. Let us take Car  for an instance. Basically car is an object and it has name, wheels, metal body, engine, maximum speed,  gear box etc as properties. Let us consider the car name is Ferrari, maximum speed is 200 km per hr with 6 gears. While driving the car driver can change the speed of the car and change the gear etc. So while car is running it's current speed, current gear are considered to be state of the object. The current speed can be changed using accelerator and gear can be changed using gear box. These can be considered as ...

　 Swing toolkit provides a component called JColorChooser to choose colors. It allows users to select color from multiple color combinations. Some times our application may need simple component with an option to select only basic colors/ less number of color options unlike sepearate dialog with too may color options[JColorChooser]. This JColorComboBox may serve the need. I wanted my color chooser to behave like JComboBox. The popup shows all 12 colors and their names, among all of them one color can be choosen. see the below image. I created two classes          1. JColorComboBox          2. ColorRenderer JColorComboBox extends the JComboBox and ColorRenderer extends JLabel and implements ListCellRenderer. import java.awt.Color; import java.awt.Component; import java.awt.Font; import java.util.Enumeration; import java.util.Hashtable; import javax.swing.*; /** * * @author sharath */ public class JCol...