Java for freshers

Hi All,     Here are the simple 10 steps for how Struts Framework will work - It is a general question in many Interviews!     Initially let us assume /login.do is our action - the result will be successful login.  Here I will explain 15 steps how/what Struts framework will do ? As end user triggerred / clicked on /login.do - > as usual it is a web application - first it will look for Web.xml So here - Web.xml loading is the first step! In Web.xml it looks for *.do mapping and it finds the Struts plug-in  i.e., ActionServelt and it loads the same. Example of Mapping:    <servlet-name>action</servlet-name>    <servlet-class>org.apache.struts.action.ActionServlet</servlet-class>    .....    <servlet-mapping>    <servlet-name>action</servlet-name>    <url-pattern>*.do</url-pattern>    </servlet-mapping> As part of load...

Java Abstraction    Abstraction is the concept of exposing only the required essential characteristics and behavior with respect to a context. Abstraction Layers          When we see a nice car on the road as a casual onlooker, we get to see the whole picture. The car as a one single unit, a vehicle. We do not see the underlying complex mechanical engineering. Now consider we are going to a showroom to buy a car. What do we see now? We see four wheels, powerful engine, power steering etc. We see the car at high level components. But, there is so much inside it which gives the completeness to the car.     Now consider a mechanic, who is going to service the car. He will see one more level deeper with more level of information.     When we design software, we take the context. In the above example, we ask the question whether we are designing the software for a causal on looker or a buyer or a mechanic? Levels of ...

OOPS concepts Tutorial Summary: By the end of this tutorial "OOPS concepts Tutorial", you will understand the meaning of OOPS concepts. Three basic concepts of OOPS Abstraction Encapsulation Polymorphism 1. Abstraction     Abstraction means using the equipment (or code) without knowing the details of working. For example, you are using your mobile phone without knowing how a mobile operates internally. Just a click on a button connects to your friend. This is abstraction. That is, the details of mobile mechanism are abstracted. Similarly we use the code of somebody to get the functionality without knowing how the code is written or working. For example, you are using printf() function to write to the DOS prompt without the awareness of what the code of printf(). One of the ways of achieving abstraction is inheritance. Through inheritance a subclass can use the super class methods as if they belong to it without caring their implementation details. 2. Encapsula...

Basic Definitions Class :     A class is a blueprint or prototype from which objects are created.                                                            (or) A Class is a template or Blue print is used to bind or group the related data members along with its related functionalities                                                            (or)     A class is a prototype that defines the variables and the methods common to all objects of a certain kind. Member Functions operate upon the member variables of the class. Object :  Objects is instance of a class it contains state and behaviors, State is nothing but variables and beha...