Site Map


Comments

Post a Comment

Popular posts from this blog

how to setup java environment variables on Window 7 or window 8 or window xp

You should follow the below steps : Step 1: Installation of JDK:  Don't forget to install JDK on your system (if  not installed) because any tomcat requires the  Java 1.5 (Java 5) and Java 1.6 (Java 6) and then set the class path (environment variable) of JDK. Step 2: Setting the class path variable for JDK: Two methods are there to set the classpath. Set the class path using the following command. set PATH="C:\Program Files\Java\jdk1.5.0_08\bin";%PATH% The other way of setting the class path variable is: First right click on the My Computer->properties->advance->Environment Variables->path. Set bin directory path of JDK in the path variable. Other operating System : Windows XP Select Start , select Control Panel . double click System , and select the Advanced tab. Click Environment Variables . In the section System Variables , find the PATH environment variable and select it. Click Edit . If the PATH environment varia...
Read more

Java Packages step by step solution with example ( what is Packages in java )

Packages are used in Java in-order to prevent naming conflicts, to control access, to make searching/locating and usage of classes, interfaces, enumerations and annotations easier etc. A Package can be defined as a grouping of related types(classes, interfaces, enumerations and annotations ) providing access protection and name space management. Some of the existing packages in Java are:: java.lang - bundles the fundamental classes java.io - classes for input , output functions are bundled in this package Programmers can define their own packages to bundle group of classes/interfaces etc. It is a good practice to group related classes implemented by you so that a programmers can easily determine that the classes, interfaces, enumerations, annotations are related. Since the package creates a new namespace there won't be any name conflicts with names in other packages. Using packages, it is easier to provide access control and it is also easier to locate the rela...
Read more

Java Abstraction step by step example

Abstraction refers to the ability to make a class abstract in OOP. An abstract class is one that cannot be instantiated. All other functionality of the class still exists, and its fields, methods, and constructors are all accessed in the same manner. You just cannot create an instance of the abstract class. If a class is abstract and cannot be instantiated, the class does not have much use unless it is subclassed. This is typically how abstract classes come about during the design phase. A parent class contains the common functionality of a collection of child classes, but the parent class itself is too abstract to be used on its own. Abstract Class: Use the abstract keyword to declare a class abstract. The keyword appears in the class declaration somewhere before the class keyword. /* File name : Employee.java */ public abstract class Employee { private String name ; private String address ; private int number ; public Employee ( String name...
Read more