Some basic questions about serialization

Hi,
I have some basic questions on serialization.
1. What are the basic criteria to make an object serializable(except that it must implement serializable ?) I mean that objects of some class inherently cannot be serialized so any object must have some features which makes it serializable/non serializable.
2. I know it makes no sense to serialize a socket because it is fixed only by specifying ip and port at both ends, and is valid only when the network connection remains valid. Still in the context of my previous question, I would like to know why a socket cannot be serialized.

Hi,
I have problems to understand you question but will do a try:
From a logical point of view objects can be only serialized reasonabely when they have a state of it's own which can be reestablished at a later point in time and space without further dependencies.
F.E. a "serialized file" would NOT make much sense cause it depends heavily on the state of the underlying file system.
You can't expected that is can be deserialized at a later point of time (physical file refered may not longer exists) or on another machine, where the serialized object was transported to.
Technical - at zero approach - it's more or less trivial. Simply implement Serializable and all non static, non transient fields of your object will be serialized automatically.
But there is a couple of pitfalls, you should study documentations regarding this feature.
Hope this helps
Martin

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Some basic questions about DAC

Hello
I am just starting to use DAC now and I have some basic questions about DAC..
1: How many different kinda image tables are there, what are they used for?
2: In order to check which ETL mapping with in the same execution plan is taking a long time, what to do? I mean is there a table that stores such info?
3: How to determine which ETL task to run after and which after?
4: Is subject area always map to the Informatica workflow folder? Or what should subject area be?
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Thanks

Hi,
I have problems to understand you question but will do a try:
From a logical point of view objects can be only serialized reasonabely when they have a state of it's own which can be reestablished at a later point in time and space without further dependencies.
F.E. a "serialized file" would NOT make much sense cause it depends heavily on the state of the underlying file system.
You can't expected that is can be deserialized at a later point of time (physical file refered may not longer exists) or on another machine, where the serialized object was transported to.
Technical - at zero approach - it's more or less trivial. Simply implement Serializable and all non static, non transient fields of your object will be serialized automatically.
But there is a couple of pitfalls, you should study documentations regarding this feature.
Hope this helps
Martin

Some basic question about SCM Installation

Hi Folks,
Could you please advice me about some basic questions about SCM and its installation -
Q1. Do I need to have an R/3 System to be able to practice OR demo the SCM system?
Q2. If, yes, which version of SCM is compatible with the ECC 5.0?
Q3. What are the basic requirements to install SCM (version compatible with ECC 5.0) and ECC on a oracle db and windows OS?
Q4. Does SCM have APO and BI as an inbuilt functionality OR does the user need to purchase these as an Add-On?
I know these are some basic questions, but these will help me give me a direction.
With best wishes,
Krishna

Hello Krishna -
Q1. Do I need to have an R/3 System to be able to practice OR demo the SCM system?
---> There are various Modules in SCM Like APO (Sub Modules DP (stand alone), SNP Needs Master data from R/3 and has to pass on transactional Data to R/3, PPDS same as SNP, GATP same as SNP), ICH needs Data from R/3 to work with. Core Interface (CIF) connects R/3 to APO for transferring data.
Q2. If, yes, which version of SCM is compatible with the ECC 5.0?
-->For thorough understanding explore the following links
http://help.sap.com/saphelp_scm41/helpdata/en/9b/954d3baf755b67e10000000a114084/frameset.htm
http://help.sap.com/saphelp_scm50/helpdata/en/9b/954d3baf755b67e10000000a114084/frameset.htm
Q3. What are the basic requirements to install SCM (version compatible with ECC 5.0) and ECC on a oracle db and windows OS?
-->Refer Above
Q4. Does SCM have APO and BI as an inbuilt functionality OR does the user need to purchase these as an Add-On?
--> APO comes with a small BI inbuilt functionality. you can only perform certain functions using that BI.
Hope this helps.
Regards,
Suresh Garg

Some basic questions about rmi registry context "bind" and "lookup"

We have more processing to do than can be accomplished with a single computer. To solve the problem I've implemented a distributed computing solution using RMI. (The first time I saw RMI was about 2 weeks ago, so please bear with me!)
The implementation is a proof of concept not a fully fleshed out system. I have one "Workunit Distributor" computer and any number of "Data Processor" computers all on the same lan segment. "Workunit Distributor" and "Data Processor" computers are both RMI client and server to each other. The "Data Processor" computers are given the ip address and name of the "Data Distributor" on the commandline when they start. They communicate their willingness to receive and process a workunit to the ""Workunit Distributor" via a RMI call. Work units are sent to available "DataProcessors" and results are eventually returned to the "WorkunitDistributor" (minutes or hours later). The model program works quite well, and appears to be capable of doing the processing we need to get done.
But now that it seems viable, I've been asked to make it a little more scalable, flexible and self configuring. In particular, instead of one "Workunit Distributor", any number of "Workunit Distributors" should be allowed to show up or disappear from the lan at any time and the system should continue to function. I've worked out a good scheme for how this can be done, but I have a couple of questions about the RMI registry (registries?). I'm trying to keep from implementing some functionality that may already be available as a library or subsystem.
With my current model design, each computer binds to its own registry with a unique name. For instance:
CRDataProcessorImpl crdpi = new CRDataProcessorImpl(svr);
Context crDataProcessingContext = new InitialContext();
crDataProcessingContext.bind("rmi:"+hostName, crdpi);
Currently the "Data Processors" get the info they need for a Context lookup() of the one and only "Workunit Distributor" from the commandline. And the info the "Workunit Distributor" needs to do a Context lookup() of a "DataProcessor" is passed to it from each "DataProcessor" via a RMI call.
But in the newer (yet to be implemented) scheme where any and all "Workunit Distributors" show up and disappear whenever they feel like, the naming bootstrapping scheme described above won't work.
I can imagine a few ways of solving this problem. For instance, having "Workunit Distributors" multicast their contact information on the lan and have a worker thread on each "Data Processor" keep track of the naming information that was multicast. Another alternative (more organized, but more complex) might be to have a dedicated host with a "well known" address and port that "Workunit Distributors" and "Data Processors" could all go to, to register or look up at an application level. Sort of a "domain name service" for RMI. But both these schemes look like a lot of work to implement , debug and maintain.
The BEST thing would be if there was one plain vanilla RMI registry that was usable by all RMI enabled computers instead of having each computer have its own local name registry. In volume 2 of the Core Java2 book it says that every registry must be local. I'm only hoping there's been progress since the book was published and now a central rmi registry is available.
If you have any ideas about this I'd like to hear what you know.
Thanks in advance for any advice.
Lenny Wintfeld
ps - I don't believe web services, as full featured as it is, is a useful alternative. I'm moving 100's (in the future possibly 1000's) of megabytes back an forth for processing.

The local bind/rebind/unbind restriction is still there and it will always be there.
I would look at
(a) RMI/IIOP, where you use COSNaming as a registry, which doesn't have that registriction, and which also has location-independent object identifiers
(b) Jini.

Some basic questions about foriegn key , and relationships.

Hi
Thank you for reading my post
I read some documents about foreugn key and tables relation ships.
but i still can not understnad some stuff.
1-when we have a foreign key , we have two tables that we want to relate them together
in a way that one of ? table columns forced to be a value from ?? table column.
what is name of those two tables , i saw , child-parent , ..... which confuse me.
can some one please tell me correct name of those two tables ?
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can you point me to some resources that help me to find answers to this questions ?
or explain them to me ?
thank you for your time.

These are critical database basics that you need to understand. I would seriously recommend getting some study in, because proper relational database design relies on the basic principle of data and relationships and a process called normalization.
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That help?

Some basic questions about Java ME

Hi,
I am new in the world of Java ME, I started to read about the technologies around it and for this reason I have some questions.
There are 2 platforms CDC and CLDC and on top of these platforms there are some profiles, for example Personal Profile for CDC or MIDP2 for CLDC. On the next level (on top of these profiles) are some JSRs which are treated as optional packages.
I saw that the CLDC emulator from SUN - WTK contains for example JSR 179 for Location based services and JSR 226 - SVG rendering. But the counterpart for CDC doesn't contain them.
How can these JSRs be added to the CDC stack? are there some implementations of these JSRs as jars or something like this? or on the JCP site are only the specifications of this JSRs and if someone wants to add these JSRs to an emulator (virtual machine) he should implement these specifications?
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Thank you

1.    String[] numString = {"1","2","345678","9","abc"};
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Some basic Questions about Solaris

Hi...
I�ve further got some problems ...
1. Can anyone tell me where i can get a list with
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For example: I would like to know how to start
the Xwindow from the bash ...
(like you can start it with startx in SuSE)
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C ya

I recommend http://sun.drydog.com/faq, which deals
with a good deal of questions concerning Solaris on
Intel PC. Ther, you will find hints and links which
enable you to go further. http://docs.sun.com is
an important site for all of Solaris documentation.
While I can't tell you how to keep X inactive and
restart it on demand (maybe lowering initdefault?),
you may choose a text session from the login
screen. X is deactivated, then, and you are
working on a full screen ascii console. Unfortionately,
as far as I know, there aren't virtual consoles like
under SCO, Interactive, or Linux. But you may
obtain and start the GPL screen program, which
provides virtual multi-terminal function on ascii
screens (even for modem-based connections).
HTH
regards, e.sanio

Some basic questions about Arch.

Hey guys, I am a newbie so bear with me please
1) I have fairly well supported hardware and don't use any fancy software. I keep hearing that rolling release causes dramas. Realistically, how often should I expect difficulties to happen?
2) How do you compare the variety of Arch repositories to that of Debian systems? What are the differences between pacman and aptitude today?
3) How does the speed and efficiency of a basic Arch system compare to Ubuntu on minimal install (I am not talking about the bloated out of the box version, I am talking about build from the ground up minimal CD).
4) Last but not least.. I never used KDE. How do you guys survive without Gnome Do? Is there some good alternative?
Thank you.

corsakh wrote:Hey guys, I am a newbie so bear with me please
Hi, we're all newbies !
corsakh wrote:2) How do you compare the variety of Arch repositories to that of Debian systems? What are the differences between pacman and aptitude today?
Variety is well sufficient because :
corsakh wrote:I [...] don't use any fancy software.
corsakh wrote:3) How does the speed and efficiency of a basic Arch system compare to Ubuntu on minimal install (I am not talking about the bloated out of the box version, I am talking about build from the ground up minimal CD).
I'd say it's better, because Arch is the best !
corsakh wrote:4) Last but not least.. I never used KDE. How do you guys survive without Gnome Do? Is there some good alternative?
I hate KDE, Arch isn't tied up to KDE, in fact it isn't tied up to anything expect maybe Pacman. If you like Gnome, well, install gnome !
Personnally I enjoy Awesome as WM and I don't have a Desktop Environnement.

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I am confused about the general use of the JAAS mechanism in Java. Hopefully someone can answer these hopefully not too naive questions:
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5. If I use JAAS for authorization in a JavaWebStart app, but I need the JNLP to include the following:
<security>
<all-permissions/>
</security>
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Some basic questions about an applet

Hi all,
I am planning to make a project in JAVA and I have some problems, which I need to solve. I am not a total beginner in JAVA but I have never made an applet. So I need to know if it is possible to make an upload of files from clients computers to servers and the second problem is if there will be some problems with printing services and applets?
Thank you all for your helpfull replies.

Read all about Applets' capabilities and (perhaps even more) incapabilities here:
http://java.sun.com/docs/books/tutorial/deployment/applet/index.html

Some basic questions about StreamWork's API

hi,
i am a student start to develop a simple Streamwork client on Android. i have some questions:
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- how to delete a activity? maybe i can't find that API on the website. and further, after i delete an activity by my laptop, and i can still use the android client the get the deleted one. if i set "status=all" in the http request. why?
thank you very much
CHEN

Hi all,
I am currently developing a similar project and ran into the same problems concerning the favorite option. It seems that it does not work as pointed out in the API documentation and that filter parameter is just ignored, all activities are shown. Can you reproduce this?
Best regards,
Michael

Very urgent! some basic questions about discoveror

1. if i made some changes to a workbook (e.g: change some conditions) on discoveror desktop,will them take effect at the same time on discoveror plus???
2. how and where can I make control for one user to access some workbooks and another user to access some other workbooks both on desktop and plus? (workbook accessibility control)
Thanks in advance,

Hi,
if i made some changes to a workbook (e.g: change some conditions) on discoveror desktop,will them take effect at the same time on discoveror plus???When you save the report using the desktop the workbook in changed for all users including the Plus,
But in order to see the change in the Plus you will have to re-login to Plus.
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This is done in the desktop as well as in Plus.
In desktop go to the tool bar "File -> Manage Workbooks -> Sharing" then choose the workbook and share it with whom ever you like.
In Plus you can find it in the tool bar "File -> Manage Workbooks" then click on any of the reports and select the "Share" from the right.
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Some basic questions about jsf

for example, a login page with two input filed(user name and password)and a "submit" button.the code is:
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<h:inputText id="username" size="12"   value="#{userBean.userName}" required="true" />
<h:outputText value="password:" />
<h:inputSecret size="12" id="pwd" value="#{userBean.pwd}" required="true" />
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     String uid;
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}in faces-config.xml i define:
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          <navigation-case>
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why? why i hava to input twice?

How are you clicking on back? Are you using the back button on your browser or a back button on your page?
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          <navigation-case>
               <from-outcome>success</from-outcome>
               <to-view-id>/index.jsp</to-view-id>
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               <to-view-id>/userLogin.jsp</to-view-id>
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     <navigation-rule>
          <from-view-id>/loginError.jsp</from-view-id>
          <navigation-case>
               <from-outcome>back</from-outcome>
               <to-view-id>/userLogin.jsp</to-view-id>
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     </navigation-rule>
You might want to try putting a back button on your error page. Have a look at the navigation rule above

Some basic questions about Reports' chart capabilities

Hi,
I'm currently surveying my options for a web based application that we are developing that requires reports with charts in HTML, PDF and Excel format.
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(1) With Oracle Reports, when charts are embedded in a PDF are they generated as bitmap or vector diagrams?
(2) I've searched around the OTN and couldn't find a complete list of the charts available within Reports - is such a list available anywhere? Are there any samples anywhere so I can get a feel of the "aesthetic" qualities of the output of Reports?
(3) Do charts support any image map or DHTML features (ie. mouseover to get textual display of numeric values).
(4) Does Reports support an Excel export capability. I don't mean a simple CSV dump of data - I mean a fully formatted Excel spreadsheet with charts, etc.
Thanks in advance for any pointers.
cheers... adam.

Hi,
(1) With Oracle Reports, when charts are embedded in a PDF are they generated as bitmap or vector diagrams? With Oracle Reports 9i, Charts are generated as gif files during the generation of PDF files, but the gif files are deleted after the PDF is generated, they are embedded in the PDF file.
(2) I've searched around the OTN and couldn't find a complete list of the charts available within Reports - is such a list available anywhere? Are there any
samples anywhere so I can get a feel of the "aesthetic" qualities of the output of Reports? Oracle reports 9i is integrated with bi bean, the complete list of the charts (bar, area, line, pie, ...) is available on Bibean doc. You can take a look at http://otn.oracle.com/products/bib/content.html.
(3) Do charts support any image map or DHTML features (ie. mouseover to get textual display of numeric values). With Oracle Reports 9i, charts support image map and hyperlink. But you need to specify when you create the chart.
(4) Does Reports support an Excel export capability. I don't mean a simple CSV dump of data - I mean a fully formatted Excel spreadsheet with charts, etc. You can't put report with charts in Excel spreadsheet.

Basic questions about CISCO IOS

Hi everybody, Jack here,
I have some basic questions about the Cisco IOS, could someone help me addressing some of them please? Any feedback would be greatly appreciated.
Basically, I have two IP addresses assigned by our Cable ISP. From what I understood you can configure a Cisco router for multiple IP addresses using the IOS, thereby allowing someone like myself to take advantage of having multiple IP addresses. This may seem unnecessary to some, but I've always wanted to put the 2nd IP address to use, since after all, I've been paying for it.
I was just wondering if someone could confirm that what I'm hoping to accomplish is indeed within the capability of the Cisco IOS (i.e. Fully utilize my 2 IP addresses). As well, if someone could kindly suggest a decent CISCO router for online gaming home use that would be super awesome!
Thank you all so much for reading through the wall of text:)
Jack

Jack
Certainly using multiple IP addresses is in the capability of Cisco IOS routers. How they can be used depends on the relationship of the IP addresses. I am assuming that we are talking about IP addresses assigned for the user to use and that the IP address for the ISP connection is not one of these that we are talking about.
If both of the IP addresses that you have been assigned are within the same subnet then you would assign one of the addresses to the router interface to establish IP communication between the router and the ISP and to enable Internet connectivity for the devices inside your network that will use the router as their gateway to the Internet. The other address that is assigned can be used for address translation and in particular for static address translation which would make one of your devices inside to be reachable for connections initiated from the Internet (if that is something that you might want to do).
If the addresses that are assigned to you are in different subnets then you could assign one address to the outside router interface and assign the other address to the router inside interface. Or you could use the second address for address translation.
I do not have much expertise with online gaming, but I would think that either the Cisco 881 router or the 890 router might be appropriate for you. If 100 Mb connection is sufficient then probably the 881 would be the one to look at. If you need Gig connection then look at the 890.
HTH
Rick

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