Calling Beans Constructor

HI
My question is two fold
1. when we use a bean like <jsp:useBean....> we create the object with no arguments
constructor, is there a way to construct an object with arguments here itself, i cant call
the argumented constructor fromk the no args coz i need to supply args there.
2. Is there a way in which an object instantiated (not as a bean) in one jsp can be used
in another?
Thanks

HIHi
>
My question is two foldHere are my suggestions
>
1. when we use a bean like <jsp:useBean....> we create
the object with no arguments
constructor, is there a way to construct an object
with arguments here itself, i cant call
the argumented constructor fromk the no args coz i
need to supply args there.
You cannot use the parameterized constructor. But you can achieve the same effect. You can write setter methods for the attributes you need to pass in constructor. In jsp you can use useBean tag as:
<jsp:useBean id="<instance name>" ... >
<jsp:setProperty name="<instance name as in useBean>"
property="<property Name like income>" ... />
</jsp:useBean>
In this case the method set<PropertyName> (in eg setIncome) will be invoke after calling the default constructor. Thus you get ensure that the object is in required state.
2. Is there a way in which an object instantiated (not
as a bean) in one jsp can be used
in another? yes.
you can put it into Http Session object.
HttpSession session=request.getSession(); //request is object of HttpServletRequest which is available in JSP
session.setAttribute("MyObject",<Object you need to access>);
Now you can access the same object in else where invoking getAttribute(String) method of Session class
ThanksHope so it solves your problem
Cheers
abhishek

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and the list to which the table is attached is also getting called multiple times.
is there a way in which the method gets called only once?
Message was edited by:
user607056

Hi!
af:table have property ContentDelivery. When <default> (lazy), the table "frame" iz rendered in first page cycle, and content (rows in table) are fetched lazy i.e. in second cycle. Thus, your backing bean is constructed twice.
If you set ContentDelivery to immediate, the table including data rows is generated in single page cycle thus your backing bean is constructed only once.
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Hi,
Thanks for your reply.
here it is my adfc-config.xml file.
<?xml version="1.0" encoding="UTF-8" ?>
<adfc-config xmlns="http://xmlns.oracle.com/adf/controller" version="1.2">
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<managed-bean-scope id="__1">backingBean</managed-bean-scope>

</managed-bean>
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Create an object instance without calling its constructor?

Hi,
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Thanks.

So the question is how to create object instance without initializing it (calling the constructor)? And if you have any info about ReflectionFactory it will be useful too.
When serializing an object you save all its fields and some extra info. When you deserialize it you have to reconstruct it, by copying the fields back, but not to reinitialize.
import java.lang.reflect.*;
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Can't You write complete example? Tried few variants but get nothing:(

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suppose there is a constructor that takes an argument
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csckid wrote:
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mahar wrote:
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Any suggestions, sorry if i oversee any 'elementary coding'....
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Thanks.
I changed the code as in example which can be compiled now.
So, i have to declare constructors without any code but with parameters only?
Can i add some specific code here? If so, which code is executed?
Now, when executing the code, the parameter is not ported..., the print.out statement shows a value of 'false' whereas i call the constructor with 'true'
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     * Launches this application
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[svn:bz-trunk] 12783: Optimizations around subtopic handling in MessageService/ ActionscriptAdapter, now we avoid calling Subtopic constructor ( which is costly) multiple times.

Revision: 12783
Revision: 12783
Author:   [email protected]
Date:     2009-12-10 06:42:14 -0800 (Thu, 10 Dec 2009)
Log Message:
Optimizations around subtopic handling in MessageService/ActionscriptAdapter, now we avoid calling Subtopic constructor (which is costly) multiple times.
Checkintests: Pass - except the usual 3 failing tests.
QA: Yes
Doc: No
Modified Paths:
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    blazeds/trunk/modules/core/src/flex/messaging/services/messaging/SubscriptionManager.java
    blazeds/trunk/modules/core/src/flex/messaging/services/messaging/adapters/ActionScriptAda pter.java

How call the constructor of the super type in the sub type?

Hi, everybody:
There are two type as belowing code:
CREATE TYEP super_t AS OBJECT (
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If can, how call?
If not, need to rewrite the code as the constructor of the super_t in the constructor of the sub_t?
Thank you very much!

No the supertype constructor is not automatically called (that should have been trivial for you to prove to yourself). Unfortunately, you can't call it from the subtype either (there is functionality like Java's 'super'). You could define a named method in the supertype that does the initialization and call that in both the constructors however.

Why Can't I call a constructor?

Hello all,
Why cant i call a constructor as a function?, just like any other function by its name?...
class Test{
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It says "Method not found" because there is no method Test() in your class, only a constructor with that name (without parameters), as already mentioned by a previous poster. Try to replace the line by new Test(); and it should work. But note that this will create a new object of the class and so, doesn't make any sense.
Think of constructors being only called when creating a new object. So you don't want "to call the constructor again", because the object already exists.
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http://java.sun.com/docs/books/tutorial/java/index.html

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// Java ain't no C++
void T::reinit() {
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}...and that ain't no C++ either ;-)
Sorry for the off-topic reply, but that code cannot stand uncorrected.delete this; Only valid for heap-constructed objects, which you can't be sure of inside the function. Will crash otherwise.
If "this" was in fact on the heap, execution might indeed reach this line:
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Enable the "calling WebIDL constructors as functions" on the web

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suppose you have the source:
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I would think the value of x is 1 which it is, but the value of y is 6, why is this, I did not call the A constructor or does an object call the parameterless constructor of its superclass automatically. If that is the case, it will clarify to me why y gets the value of 6 and not 5.

Unless you specify a super call, it will be done. The next two constructors are the same:public B () {
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Kind regards,
Levi

Calling Beans Constructor

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