Changing Java class in to Java Bean

Can somebody tell me how to change a normal Java class into Java Bean.I dont need any visual interface in Java Bean.I simple need to turn my Java class into Java Bean.

Hi,
Chanchal,
you didn't specify anything abt ur java class. In a java bean basically you use getter and setter methods to call. import relevant packages and extend them into your class. If u give sufficient info, then i can help you out.
Durga

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Changing Java class into Java Bean

Can anybody tell me how to change a Java class into simple Java Bean.I dont need any visual interface of Java Bean.I simply want to turn my Java class into Java Bean.

You can use almost any class as a java bean.
To be a bean it must
1 - Have a constructor which takes no arguments (so it can be instantiated)
2 - For properties/attributes which you want to have readable/writable, provide get / set methods of the appropriate type.
Thats it.

Question about main difference between Java bean and Java class in JSP

Hi All,
I am new to Java Bean and wonder what is the main difference to use a Bean or an Object in the jsp. I have search on the forum and find some post also asking the question but still answer my doubt. Indeed, what is the real advantage of using bean in jsp.
Let me give an example to illustrate my question:
<code>
<%@ page errorPage="errorpage.jsp" %>
<%@ page import="ShoppingCart" %>

<jsp:useBean id="cart" scope="session" class="ShoppingCart" />
<html>
<head><title>Shopping Cart</title></head>
<body bgcolor="#FFFFFF">
Your cart's ID is: <%=cart.getId()%>.
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In the above code, I can also create a object of ShoppingCart by new operator then get the id at the following way.
<code>
<%
ShoppingCart cart = new ShoppingCart();
out.println(cart.getId());
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Now my question is what is the difference between the two method? As in my mind, a normal class can also have it setter and getter methods for its properties. But someone may say that, there is a scope="session", which can be declared in an normal object. It may be a point but it can be easily solved but putting the object in session by "session.setAttribute("cart", cart)".
I have been searching on this issue on the internet for a long time and most of them just say someting like "persistance of state", "bean follow some conventions of naming", "bean must implement ser" and so on. All of above can be solved by other means, for example, a normal class can also follow the convention. I am really get confused with it, and really want to know what is the main point(s) of using the java bean.
Any help will be highly apprecaited. Thanks!!!
Best Regards,
Alex

Hi All,
I am new to Java Bean and wonder what is the main
difference to use a Bean or an Object in the jsp. The first thing to realize is that JavaBeans are just Plain Old Java Objects (POJOs) that follow a specific set of semantics (get/set methods, etc...). So what is the difference between a Bean and an Object? Nothing.
<jsp:useBean id="cart" scope="session" class="ShoppingCart" />
In the above code, I can also create a object of
ShoppingCart by new operator then get the id at the
following way.
ShoppingCart cart = new ShoppingCart();
out.println(cart.getId());
...Sure you could. And if the Cart was in a package (it has to be) you also need to put an import statement in. Oh, and to make sure the object is accessable in the same scope, you have to put it into the PageContext scope. And to totally equal, you first check to see if that object already exists in scope. So to get the equivalant of this:
<jsp:useBean id="cart" class="my.pack.ShoppingCart"/>Then your scriptlet looks like this:
<%@ page import="my.pack.ShoppingCart %>
<%
ShoppingCart cart = pageContext.getAttribute("cart");
if (cart == null) {
    cart = new ShoppingCart();
    pageContext.setAttribute("cart", cart);
%>So it is a lot more work.
As in my mind, a normal class can also
have it setter and getter methods for its properties.True ... See below.
But someone may say that, there is a scope="session",
which can be declared in an normal object.As long as the object is serializeable, yes.
It may be
a point but it can be easily solved but putting the
object in session by "session.setAttribute("cart",
cart)".Possible, but if the object isn't serializable it can be unsafe. As the point I mentioned above, the useBean tag allows you to check if the bean exists already, and use that, or make a new one if it does not yet exist in one line. A lot easier than the code you need to use otherwise.
I have been searching on this issue on the internet
for a long time and most of them just say someting
like "persistance of state", "bean follow some
conventions of naming", "bean must implement ser" and
so on. Right, that would go along the lines of the definition of what a JavaBean is.
All of above can be solved by other means, for
example, a normal class can also follow the
convention. And if it does - then it is a JavaBean! A JavaBean is any Object whose class definition would include all of the following:
1) A public, no-argument constructor
2) Implements Serializeable
3) Properties are revealed through public mutator methods (void return type, start with 'set' have a single Object parameter list) and public accessor methods (Object return type, void parameter list, begin with 'get').
4) Contain any necessary event handling methods. Depending on the purpose of the bean, you may include event handlers for when the properties change.
I am really get confused with it, and
really want to know what is the main point(s) of
using the java bean.JavaBeans are normal objects that follow these conventions. Because they do, then you can access them through simplified means. For example, One way of having an object in session that contains data I want to print our might be:
<%@ page import="my.pack.ShoppingCart %>
<%
ShoppingCart cart = session.getAttribute("cart");
if (cart == null) {
    cart = new ShoppingCart();
    session.setAttribute("cart", cart);
%>Then later where I want to print a total:
<% out.print(cart.getTotal() %>Or, if the cart is a JavaBean I could do this:
<jsp:useBean id="cart" class="my.pack.ShoppingCart" scope="session"/>
Then later on:
<jsp:getProperty name="cart" property="total"/>
Or perhaps I want to set some properties on the object that I get off of the URL's parameter group. I could do this:
<%
ShoppingCart cart = session.getAttribute("cart");
if (cart == null) {
    cart = new ShoppingCart();
    cart.setCreditCard(request.getParameter("creditCard"));
    cart.setFirstName(request.getParameter("firstName"));
    cart.setLastName(request.getParameter("lastName"));
    cart.setBillingAddress1(request.getParameter("billingAddress1"));
    cart.setBillingAddress2(request.getParameter("billingAddress2"));
    cart.setZipCode(request.getParameter("zipCode"));
    cart.setRegion(request.getParameter("region"));
    cart.setCountry(request.getParameter("country"));
    pageContext.setAttribute("cart", cart);
    session.setAttribute("cart", cart);
}Or you could use:
<jsp:useBean id="cart" class="my.pack.ShoppingCart" scope="session">
<jsp:setProperty name="cart" property="*"/>
</jsp:useBean>The second seems easier to me.
It also allows you to use your objects in more varied cases - for example, JSTL (the standard tag libraries) and EL (expression language) only work with JavaBeans (objects that follow the JavaBeans conventions) because they expect objects to have the no-arg constuctor, and properties accessed/changed via getXXX and setXXX methods.
>
Any help will be highly apprecaited. Thanks!!!
Best Regards,
Alex

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i am using java bean model in my Web Dynpro Application.
for that one i have created command bean(Customer) and in my command bean i am using some other class(CustomerInfo) as reference. this CustomerInfo class contains 4 attribtes(name ,id ,etc all are of type String)
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>
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hello,
test.java
public class test
public class in
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t.java
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class t
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Thanks

Muthu wrote:
How can we generate dynamic Java bean classes for XSD (dynamically support All XSD at runtime)?
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Please please help me sort this problem out. Thanks in advance

hey ... i just found a way out .... when i upgraded to version 6 the error simply vanished ... seems there was a bug in d previous version for the XMLEncoder class. Thanks anyway.
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Thanks for you help
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Where to put the java bean classes

Hi,
I am very new to the web service developer pack. I have written a java bean but don't know which directory to place it. Can anyone please tell mi???
Thanks

put in
WEB-INF/classes
if is a jar file
put in
WEB-INF/lib
regards

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Changing Java class in to Java Bean

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