Buddhika Disanayaka

Hi Sangel Kapoor,

Spring framework consist of many features. Based on your question, to understand what DI or IOC, please look into this code segment.
//Segment - 1 public class Human { private Heart heart; public Heart getHeart() { return heart; } public void setHeart(Heart heart) { this.heart = heart; } }

//Segment - 2 public class Heart { }

See the Human class and it contains a reference to Heart class as a private property.
If you want to set a heart object to Human , Then you have to write following code.

//Segment - 3 Human human = new Human(); human.setHeart(new Heart());

But what DI or dependency injection does is setting the heart object to human during run-time.
So you do not need to write code to set the heart object.
If you use spring DI feature you do not need to write above code Segment-3.
That will be done by spring dependency injection.
(Heart is a dependent of Human, So spring has injected the dependent,Heart into Human. That's that we call Dependancy injection)

Any how even without people can develop java applications.
But spring provide some easy ways of doing things, provide some features(eg: DI, IOC), provide a platform for application development and enforce best practices ect.
To learn more about Spring you can find many articles on the internet. Below is an introduction.
http://docs.spring.io/spring-framework/docs/current/spring-framework-reference/html/overview.html

Ok. thank you Jeanne.

mm mm.. But what is the purpose of integrating two frameworks(Struts 2 and Spring for back end) if spring framework with spring mvc provide all the functionalities that struts 2 can provide?

Hi Thang,

If you use spring mvc and spring framework for back end you have spring framework’s Dao module that makes database integration easy.
That provide easy integration with hibernate, jpa or jdbc.
And another useful module that spring provides is spring security which provides a framework to handle security of the application.
Other than that spring framework comes with some features like transaction handling , mail handling ect which are not available in Struts 2.
Other than that spring provide some other things like spring web services, AOP ect.

Thanks,
Buddhika

You are welcome. Good luck.

According to this statement it says that Spring AOP provides an extra service to existing Spring IoC .
So Spring AOP acts as a middleware for Spring IoC.

Hi David,

According to your error log, It says that you have missed a jar file that contains a class called LogFactory.
So please download below jar file and add it into your eclipse build path and try again once.
http://commons.apache.org/proper/commons-logging/download_logging.cgi

Thanks,

Run following code and check. Hope that is the functionality you want.

import java.awt.*; import java.awt.event.*; import javax.swing.*; public class Bank1 extends JFrame { private JLabel l1; private JLabel l2; private JTextField t1; private JPasswordField p1; private JButton b1; public Bank1() { super("Bank System"); Container container = getContentPane(); container.setLayout(new FlowLayout()); l1=new JLabel(" ID :- "); container.add(l1); t1=new JTextField(25); container.add(t1); l2=new JLabel(" Password :- "); container.add(l2); p1=new JPasswordField(25); container.add(p1); b1=new JButton("Enter"); container.add(b1); ButtonHandler handler = new ButtonHandler(); b1.addActionListener(handler); setSize(400,150); setVisible(true); } public static void main (String args[]) { Bank1 application = new Bank1(); application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } private class ButtonHandler implements ActionListener { public void actionPerformed(ActionEvent event) { /*String msg; msg = "Login Successful"; JOptionPane.showMessageDialog(null, msg);*/ JFrame secondFrame = new JFrame("Second Frame"); secondFrame.setSize(600, 500); secondFrame.setVisible(true); dispose(); } } }

Hint : first think about java exception catching order.

Hi,

I have heard the name ‘Portal framework’ in many places. But I don’t know what it is. Tell me what a portal framework is and give me some examples for portal frameworks in java.

Thanks.

Try to deploy a EJB in a web server. you cant to that. Read 65th page of 'Head first Servlet and JSP' book.

I cant agree with jishnu's answer.Normally you can assign a subtype object to its super type reference. But in java generics it’s not applicable. By putting <Number> after List reference, you are telling that reference listNumber can hold lists only with the same generic type. Write below code and try to compile. That compiles without any problem.
List<? extends Number> listNumber = new ArrayList<Float>();
That's how java generics behave.Refer 7th chapter, ‘Generics and Collections’ in 'SCJP Sun Certified Programmer for Java 5 Study Guide' book witch was written by Kathey Sierra to get a better understanding about java generics.

Yes,
Thread.sleep(1000); is about main thread according to your program. But the exception you are getting is not a problem of that thread.Have can you seen that main method of your program has an argument of String array ,String[] args. and you are trying to get the first element of args array by calling args[0] in 4th line of your code.Trying to retrieve an element from an empty array generates an ArrayIndexOutOfBoundsException.To avoid this error you have to provide a command line argument that can be parse to an interger (eg: 10,29).Search google for "command line arguments java" to find how you can give command line arguments to a java program.

I feels like you have asked a broad question that I cant give a direct answer at once.Normally proper way to develop an application is described by 'Software Development Models' like waterfall model, spiral model ect. I think you can get a very accurate answer by narrowing your question or being specific.Or if you have a problem in design,better try it posting the question in "OO, Patterns, UML and Refactoring" section of the forum.