Mixing Generics And Non-Generics Code


If we are work on code that uses generics that is fine and what will happen if we want to mix both generic and non generic code. Consider below Animal class also read: New Features in Java 5.0 Generics in Java 5.0 Annotations in Java 5.0 if we create the list like below will it […]

How to use ? extends in Generics?


In generics as we know we can not assign subclass generic type to super class generic type, for example will not compile even though Dog IS-AN Animal. the reason for this is already explained in generics basics section. How can we solve this particular problem????? we can solve this problem by using wildcard in generics, […]

Using ? super in generics – Java 5.0


As we know we can not add any value except null to collection if we use ? extends syntax. What if we want to add value to the collection, then we have to use ? super syntax. The code looks like this. also read: New Features in Java 5.0 Generics in Java 5.0< Annotations in […]

Generic Methods in Java 5.0


In java 1.5 we have a feature called generic methods, with this we can write a method, which can be generic, means it can be called by any parameter and behavior of the method will be according to the parameter passed. Assume that we need to write a method which takes an array and converts […]

Handle exceptions in overriding methods


The question why makes any topic makes more clearer and interesting than just to know about what the concept is. The rule about exceptions when we use them in overriding is: If super class method is throwing any exception(checked) and if we are overriding that method in sub class. also read: New Features in Java […]

Request Lifecycle in Struts 2.0 applications


1User Sends request: User sends a request to the server for some resource. FilterDispatcher determines the appropriate action: The FilterDispatcher looks at the request and then determines the appropriate Action. Interceptors are applied: Interceptors configured for applying the common functionalities such as workflow, validation, file upload etc. are automatically applied to the request. Execution of […]

Struts 1.0 Vs Struts 2.0


Difference between Struts 1.0 and Struts 2.0 In the following section, we are going to compare the various features between the two frameworks. Struts 2.0 is very simple as compared to struts 1.0,1.1, few of its excelent features are: 1.Servlet Dependency also read: Struts 2 Tutorials Struts Interview Questions Struts and Spring Integration Actions in […]

Life Cycle of JSF Components


Restore View The JSF servlet builds the view of the requested page as a component tree that contains the information associated with all components. It also saves the view in a FacesContext instance, thereby making it possible to repopulate the page if necessary—for example, when the user doesn’t fill out a form as required. If […]

Hiding and Overriding Methods In Java


Now in section Inheritance mainly in Hiding And Overriding Methods can we predict the output of the following program? also read: Java Tutorials Java EE Tutorials Design Patterns Tutorials Java File IO Tutorials It Prints: Here the overriding methods getX and getY in class RealPoint have the same return types as the methods of class […]

Static keyword in Java


What is Static? static variables and static methods might better have been called perClass variables and methods. They inherited this misleading terminology from C++. They are the opposite of instance variables and methods that work on a particular object. also read: Java Tutorials Java EE Tutorials Design Patterns Tutorials Java File IO Tutorials Can we […]