Why we need externalizable interface in java

Hi friends,
I know the Concept of serliazation and externalization, apart from this concept i have one doubt about externalization, I feel both are doing same work. Then what is the nedd of externalizable interface. Can anyone tell what is the difference of Serialization ans Externalization, if both are doing same work.

Crosspost: http://forum.java.sun.com/thread.jspa?threadID=5226495&tstart=0
Don't crosspost, it's rude and a waste of time and energy for all involved.
People on the forum help others voluntarily, it's not their job.
Help them help you.
Learn how to ask questions first: http://faq.javaranch.com/java/HowToAskQuestionsOnJavaRanch
(Yes I know it's on JavaRanch but I think it applies everywhere)
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Why do we need write access to Java installation Directory

We are Upgrading from Siebel Analytics 7.8 to OBIEE 10.1.3.4.
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I had this same question and asked Oracle. Here's what I was told:
Per Dev:
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Why we need Java Class in c++ pof Serialization

Hi,
I'm really confused why we need java class which implements PortableObject to support complex objects of c++. If we are not using any queries or entry processors in the application can't we keep the object as serialized byte format and can't we retrieve in from the c++ deserialization.
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regards,
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feel both are doing same work. Also can anyone tell me what is teh difference between Serilization and Exgternalization.If you need someone to tell you the difference, (a) how can you possibly 'feel both are doing the same work'? and (b) why don't you look it up in the Javadoc?
It's not a secret.

Why we need reference in java?

Hi
I faced one problem while I was doing heapdump analysis.I had to find memory leak suspect.
Somewhere in parent node I have found soft reference.
My question is that why we need reference in java?
and why IBM jdk1.4.2 and above have inbulit class like
softreference
weakreference
phatomreference

These Reference objects have special ways of interacting with the garbage collecor. A normal reference is, in comparison, called a "hard" reference. If an object is only reachable through a special reference it is said to be "softly reachable" or the like, and the garbage collector can collect it. When this happens the reference object is cleared, and will return null if you try to acccess the object through it.
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Why does EJB needs two interface???

Hi All,
This has been asked by many ppl and many of you might be having
the correct answer for it. Please tell me....
Why does EJB needs two interface (Home and Remote Interface)?. Why not one?
Thanx to all...
Regards
GoodieGuy

Hi Goodie ,
Its good question and its a very valid one , one has to have doubt
why two , why not one ..
Here the answer goes ..
First of all you need to understand that its a distributed computing technique ie I mean lot of people will be accessing the bean at the same time , right ? OK , you cann't access the bean directly.
and lastly the stateless and entity beans do instance pooling.
The very purpose of having two interfaces is
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2) The home interface inititates life cycle methods like creation , destruction etc .
3) There are lot of beans in the container , and through home you are
creating the instance or accessing one of them .
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In ejb 1.0 and 1.1 even though the bean and the client are in same jvm its assumed that they are remote and in 2.0 Ver we have local this is to avoid network traffic .
Hope you have got the answer , but if u still need clarification
read EBRoman book first and second chapters thoroughly and then proceed
a head.
Bye
Mahesh L.
============

Need Info Regarding Implementaion of Interfaces in java.sql package

Hi All,
I am interested in knowing details abt how the Interfaces in the java.sql package are implemented. We all work with the database using the interfaces provided ,but how do they work at the backend ? How can a Interface provide details (work ) with out an implementation class.I Is this taken care by the JVM or some of the Call level interfaces? Please do provide details abt this..

hi Sheshadri,
The implementation of the various interfaces in
java.sql package are provided by your jdbc driver,
which also manages the connection and communication of
your java program with the appropriate database.
cheers,
-Jer

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Why we need abap XI ?

why we need abap XI with one business scenario?

Hi Narendra,
Good Check this documentation and corresponding links
SAP Exchange Infrastructure
Purpose
SAP Exchange Infrastructure (SAP XI) enables you to implement cross-system processes. It enables you to connect systems from different vendors (non-SAP and SAP) in different versions and implemented in different programming languages (Java, ABAP, and so on) to each other. SAP Exchange Infrastructure is based on an open architecture, uses open standards (in particular those from the XML and Java environments) and offers those services that are essential in a heterogeneous and complex system landscape:
●     Modeling and design of messages, transformations, and cross-component integration processes
●     Configuration options for managing collaborative processes and message flow
●     Runtime for message and process management
●     Adapter Engine for integrating heterogeneous system components
●     Central monitoring for monitoring message flow and processes
SAP XI supports internal company scenarios and cross-company scenarios.
https://www.sdn.sap.com/irj/sdn/developerareas/xi
http://help.sap.com/saphelp_nw04/helpdata/en/0f/80243b4a66ae0ce10000000a11402f/content.htm
http://help.sap.com/saphelp_nw04/helpdata/en/14/80243b4a66ae0ce10000000a11402f/frameset.htm
http://www.sap-press.com/product.cfm?account=&product=H1950
see following links,
https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/e1532f46-0a01-0010-bc88-af3272254881
https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/e1532f46-0a01-0010-bc88-af3272254881
/people/sap.user72/blog/2005/05/31/my-experience-with-xi-installation-on-fedora-core-3-linux
https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/95d7d490-0301-0010-ce93-c58f9a3cde0b
http://help.sap.com/bp_bpmv130/Documentation/Installation/XI30InstallGuide.pdf
http://help.sap.com/bp_bpmv130/Documentation/Installation/Configuration_Guide_FP.pdf
check out these threads
XI installation
XI installation
http://help.sap.com
Introduction to XI technology
XI Materials
XI Material
/people/sravya.talanki2/blog/2006/12/25/aspirant-to-learn-sap-xiyou-won-the-jackpot-if-you-read-this-part-i
/people/sravya.talanki2/blog/2006/12/26/aspirant-to-learn-sap-xiyou-won-the-jackpot-if-you-read-this-part-ii
/people/sravya.talanki2/blog/2006/12/27/aspirant-to-learn-sap-xiyou-won-the-jackpot-if-you-read-this-part-iii
then practice the following scenario's you will get every thing about XI
1. Aspirant to learn SAP XI...You won the Jackpot if you read this!-Part I /people/sravya.talanki2/blog/2006/12/25/aspirant-to-learn-sap-xiyou-won-the-jackpot-if-you-read-this-part-i
2. Aspirant to learn SAP XI...You won the Jackpot if you read this!-Part II /people/sravya.talanki2/blog/2006/12/26/aspirant-to-learn-sap-xiyou-won-the-jackpot-if-you-read-this-part-ii
3. Aspirant to learn SAP XI...You won the Jackpot if you read this!-Part III /people/sravya.talanki2/blog/2006/12/27/aspirant-to-learn-sap-xiyou-won-the-jackpot-if-you-read-this-part-iii
and once you are through ...follow the following links to weblogs which explain all the basic scenarios in XI
Following are the links to weblogs which will help to develop the basic scenarios.
/people/prateek.shah/blog/2005/06/08/introduction-to-idoc-xi-file-scenario-and-complete-walk-through-for-starters - IDoc to File
/people/ravikumar.allampallam/blog/2005/03/14/abap-proxies-in-xiclient-proxy - ABAP Proxy to File
/people/sap.user72/blog/2005/06/01/file-to-jdbc-adapter-using-sap-xi-30 - File to JDBC
/people/prateek.shah/blog/2005/06/14/file-to-r3-via-abap-proxy - File to ABAP Proxy
/people/venkat.donela/blog/2005/03/02/introduction-to-simplefile-xi-filescenario-and-complete-walk-through-for-starterspart1 - File to File Part 1
/people/venkat.donela/blog/2005/03/03/introduction-to-simple-file-xi-filescenario-and-complete-walk-through-for-starterspart2 - File to File Part 2
/people/ravikumar.allampallam/blog/2005/06/24/convert-any-flat-file-to-any-idoc-java-mapping - Any flat file to any Idoc
/people/arpit.seth/blog/2005/06/27/rfc-scenario-using-bpm--starter-kit - File to RFC
https://www.sdn.sap.com/irj/sdn/weblogs?blog=/pub/wlg/1685 [original link is broken] [original link is broken] [original link is broken] [original link is broken] - File to Mail
/people/jayakrishnan.nair/blog/2005/06/20/dynamic-file-name-using-xi-30-sp12-part--i - Dynamic File Name Part 1
/people/jayakrishnan.nair/blog/2005/06/28/dynamic-file-namexslt-mapping-with-java-enhancement-using-xi-30-sp12-part-ii - Dynamic File Name Part 2
/people/michal.krawczyk2/blog/2005/03/07/mail-adapter-xi--how-to-implement-dynamic-mail-address - Dynamic Mail Address
/people/siva.maranani/blog/2005/05/25/understanding-message-flow-in-xi - Message Flow in XI
/people/krishna.moorthyp/blog/2005/06/09/walkthrough-with-bpm - Walk through BPM
/people/siva.maranani/blog/2005/05/22/schedule-your-bpm - Schedule BPM
/people/sriram.vasudevan3/blog/2005/01/11/demonstrating-use-of-synchronous-asynchronous-bridge-to-integrate-synchronous-and-asynchronous-systems-using-ccbpm-in-sap-xi - Use of Synch - Asynch bridge in ccBPM
https://www.sdn.sap.com/irj/sdn/weblogs?blog=/pub/wlg/1403 [original link is broken] [original link is broken] [original link is broken] [original link is broken] - Use of Synch - Asynch bridge in ccBPM
/people/michal.krawczyk2/blog/2005/08/22/xi-maintain-rfc-destinations-centrally - Maintain RFC destination centrally
/people/sravya.talanki2/blog/2005/08/18/triggering-e-mails-to-shared-folders-of-sap-is-u - Triggering Email from folder
/people/sravya.talanki2/blog/2005/08/17/outbound-idocs--work-around-using-party - Handling different partners for IDoc
/people/siva.maranani/blog/2005/08/27/modeling-integration-scenario146s-in-xi - Modeling Integration Scenario in XI
/people/michal.krawczyk2/blog/2005/08/25/xi-sending-a-message-without-the-use-of-an-adapter-not-possible - Testing of integration process
/people/michal.krawczyk2/blog/2005/05/25/xi-how-to-add-authorizations-to-repository-objects - Authorization in XI
http://help.sap.com/saphelp_nw04/helpdata/en/58/d22940cbf2195de10000000a1550b0/content.htm - Authorization in XI
/people/michal.krawczyk2/blog/2005/09/09/xi-alerts--step-by-step - Alert Configuration
/people/michal.krawczyk2/blog/2005/09/09/xi-alerts--troubleshooting-guide - Trouble shoot alert config
/people/sameer.shadab/blog/2005/09/21/executing-unix-shell-script-using-operating-system-command-in-xi - Call UNIX Shell Script
/people/sravya.talanki2/blog/2005/11/02/overview-of-transition-from-dev-to-qa-in-xi - Transport in XI
/people/r.eijpe/blog/2005/11/04/using-abap-xslt-extensions-for-xi-mapping - Using ABAP XSLT Extensions for XI Mapping
/people/prasad.ulagappan2/blog/2005/06/07/mail-adapter-scenarios-150-sap-exchange-infrastructure - Mail Adaptor options
/people/pooja.pandey/blog/2005/07/27/idocs-multiple-types-collection-in-bpm - Collection of IDoc to Single File
/people/sap.user72/blog/2005/11/17/xi-controlling-access-to-sensitive-interfaces - Controlling access to Sensitive Interfaces
/people/michal.krawczyk2/blog/2005/11/10/xi-the-same-filename-from-a-sender-to-a-receiver-file-adapter--sp14 - The same filename from a sender to a receiver file adapter - SP14
/people/prasad.illapani/blog/2005/11/14/payload-based-message-search-in-xi30-using-trex-engine - Payload Based Message Search in XI30 using Trex Engine
/people/sap.user72/blog/2005/11/24/xi-configuring-ccms-monitoring-for-xi-part-i - XI : Configuring CCMS Monitoring for XI- Part I
/people/michal.krawczyk2/blog/2005/11/23/xi-html-e-mails-from-the-receiver-mail-adapter - XI: HTML e-mails from the receiver mail adapter
/people/sap.user72/blog/2005/11/22/xi-faqs-provided-by-sap-updated - XI : FAQ's Provided by SAP
Good Luck and thanks
AK

What is the diffrence between My Runnable Interface and Java Runnable

Hi folks
all we know that interfaces in java just a decleration for methods and variables.
so my Question is why when i create an interface its name is "Runnable" and i declared a method called "run" inside it.then when i implements this interface with any class don't do the thread operation but when i implement the java.lang.Runnable the thread is going fine.
so what is the diffrence between My Runnable Interface and Java Runnable?
thnx

Hi folks
all we know that interfaces in java just a decleration
for methods and variables.
so my Question is why when i create an interface its
name is "Runnable" and i declared a method called
"run" inside it.then when i implements this interface
with any class don't do the thread operation but when
i implement the java.lang.Runnable the thread is going
fine.
so what is the diffrence between My Runnable Interface
and Java Runnable?
thnxClasses and interfaces are not identified by just their "name", like Runnable. The actual "name" the compiler uses is java.lang.Runnable. So even if you duplicate the Runnable interface in your own package, it's not the same as far as the compiler is concerned, because it's in a different package.
Try importing both java.util.* and java.awt.* (which both have a class or interface named List), and then try to compile List myList = new ArrayList();

Use of Externalizable Interface

Hi All,
can any of you please tell me that what is the exact use of Externalizable Interface and when do we need to use Externalizable instaed of Serializable.
Thanks in advance.

Use the Externalizable interface when you need complete control over your Bean's serialization.
For example, you want to make a serialization process into a different file format ( file content structure)
Regards,
Alan Mehio
London,UK

Why use customized / particular exceptions instead java.lang.Exception

Hi,
Do any of you guys know where can I find a theorical statement / explanation about why use particular / customized exceptions instead java.lang.Exception? I am aware that it consumes more resources and becomes a heavier object, as well as the clearness when coding and all that stuff; however, my boss wants to see a tech document where all this is clearly stated. Any resource over there?
Regards

It is better to throw specific--or at least module- or
package-specific--excpetions, rather than Exception,
because then the caller knows what to expect. However,
if you declare "throws Exception", the caller can
still catch IOException, SQLException, etc.,
separately. He'll just have to be a really good
guesser as to which ones he should catch.True.
Also, there's no point in declaring "throws
NullPointerException." Any method can throw it without
declaring it. If you generate your own NPE (or other
unchecked exception) inside the method, then you
should document it in the javadoc comments, but you
don't need to put it in the throws clause. It doesn't
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I'm assuming overhead caused by extending classes.At
the worst, it would be miniscule, or so I wouldthink.
What overhead is created by extending classes?Hmm, I was under the impression that a class the extended another class, inherited all of the other classes data (variables, etc.). Hence, you get something like this:
SuperClass1 + SubClass1 + SubClassOfSubcCass1 = Memory usuage for SubClassOfSubClass1.
Since adding postivie number will always end up increasing data, SubClassOfSubClass1 will use more dtat than SuperClass1.
Am I wrong?

Why we need doGet() or doPost() instead of service()

Though we have service() method in http servlet why we need to override the doGet() or doPost() of Httpservlets
2services methods are availbale in HttpServlets
1.protected void service( Httpservelt request hreq, HttpServletResponse hresp);
2. Public void service( servletRequest req, servletResponse resp)
Read this and tell how it is(it was collected from documentation of Jguru site)
NOTE: the doGet() and doPost() methods (as well as other HttpServlet methods) are called by the service() method.

The service() method from the Servlet interface is overloaded in HttpServlet to accept HttpServletRequest and HttpServletResponse. If you read the API documentation, you will note that it says the overloaded service() method will dispatch to doGet, doPost, doPut, etc. based on the type of request.
This approach makes sense, because it is bad design to put all your code in one method, or one class for that matter. Usually the doGet/doPost/do<Whatever> methods are themselves dispatcher methods that call the proper classes/methods based on the logical contents of the request.
This is in fact a common pattern in servlet frameworks like Struts and Spring. Said frameworks use a generic DispatcherServlet that redirects requests to the appropriate classes/beans as declared in the configuration files.

Why we need specification and body in Packages

Hi all
Why we need specification and body in packages
is Package body is not enough?
It is an interview question asked
How can I explain
regds

1. Package specification is the interface.
Package body is the implementation or detail code.
If one has built a package, he/she just need to publishs
the interface without a need to publish the detail implementation, so it will simplify to end user by hiding the detail.
2. Using only a Package body is identical to make separate subroutine. One pkg body will need one subroutine, if there are 10 pkgs body there will be 10 individual subroutine. Using package will give simplicity to manage the code, and also give speed in execution.

You may need to reinstall supported java virtual machine to load.

Friends,
I am getting below message, when i am running PSMPPIAInstall to build the PIA.
could not find hava virtual machine to load.
You may need to reinstall supported java virtual machine to load.
I have downloaded and install jrockit present in PT 8.52 at the location d:\bea\jrocket*
I can see java -version
D:\psoft\PT8.52>java -version
java version "1.6.0_20"
Java(TM) SE Runtime Environment (build 1.6.0_20-b02)
Oracle JRockit(R) (build R28.1.0-123-138454-1.6.0_20-20101014-1351-windows-x86_6
4, compiled mode)
weblogic is installed correctly.
kindly guide.

Datacenter, hmm ...
I have always installed it on Enterprise or Standard edition without any issues with the software delivered from eDelivery.
But why use Datacenter, this is more to be used for virtualisations?

Is anyone know how to run the examples in 3d user interfaces with java 3d

hi dear ,
I am trying to run the examples in 3d user interfaces with java 3d.
I hope i can load the library in jcreator. but the libarary for this book are classes files , it do not have jar file for it . the jcreator do not read these classes . i do not know why ? i am wonder if there any one run these code before can give me some idear .
thanks so much .
the code u can get from this link.
http://www.manning.com/books/barrilleaux/source
thank you for u to have a look for me .
regards
xiaocui

<h2>{color:red}CROSS POSTED{color}</h2>
[t-5289810]
Cross posting is rude.
db

Why we need externalizable interface in java

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