Generics - where to use them?

I'm brushing up on Java 5.0, I'm at 'generics' - I always hated c++ templates and knew they would catch up with me sooner or later...
I have a fairly simple question about where and how to use them, conceptually.
Am I correct in thinking that they are primarily concerned with items contained within a class and passed to a class?
I'm trying to find a useful bit of code to write to practice with them and I've been half tempted to re-write something that uses lots of inheritance simply because I know the code in question needed a lot of casting, but my gut feeling is that generics doesn't have an awful lot to do with inheritance and re-jigging a class that relied on inheritance to use generics is barking up the wrong tree.
I'd really appreciate some informed comments before I go trundling off down a path that is going to end with reams of pointless code.
Thanks,
Steve

I understand all the semantics and how they work, but
as with everything in software its about where they
would be used. Experience is obviously the best
teacher, but I'm just trying to get some pointers
before I start off.
I think my original question about whether they were
relevant where inheritance has been used is the crux
of what I'm asking. I've read all the documentation,
I just need a few pointers about the conceptual side
of things.Then why don't you look at Peter's blog? It's not documentation, it shows usage and design, specifically with inheritance as you seem concerned about. If you don't think Peter is qualified to write on the subject then I don't know what to tell you. Angelika Langer's FAQ also addresses design, you have links to both. If those don't help then maybe be more specific?
Hopefully you didn't take my indignation seriously, the "/sarcasm" should have been enough to make the intent clear.

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Questions on preview quality and where Aperture uses them

I have been reading Apple's Aperture articles about preview quality and how Aperture shares images with the outside world. I had always assumed that the full quality image in Aperture was used for printing, exporting and sharing, but it seems that, at least for sharing, it is the preview that Aperture creates that is shared.
I have just increased the quality of the previews that Aperture generates from 5 to 9 and forced Aperture to re-render all previews. It seems to me that the images on screen and in slide shows and other iLife documents, are now much clearer and brighter (the downside of this is that my Aperture library file has grown by 4 gigabytes).
This leads me to ask four questions about Aperture and preview use (if I may?).
Is a jpeg on a high setting (9) visibly better than one on a medium setting (5), or am I being led to see what I expect to see?
Apart from editing, slideshows and iLife and iWork documents, in what situations does Aperture use previews where high or low quality might make a difference?
Does Aperture use previews to compile photo books? If so, does the quality of the preview affect the quality of the final printed book?
Is it possible to set Aperture to produce high quality previews for images above a certain star rating and low quality previews for the rest?
Thanks for any answers you may have.
Alasdair

Previews are used within Aperture to quickly show an image in the main viewer before the master has been fully loaded, they are also used to see the referenced masters even if the external location is not available at that moment (not adjustments can be done then, but at least you can see the image)
Previews are used outside Aperture to share the images with adjustments without exporting every image. It comes in handy that you can drag an image from Aperture's browser to another app or the desktop (what you get there is the preview). iMovie or other iApps use previews, the bigger size and quality the better quality you'll get.
Once you set up the size and quality of the previews in Aperture's Preferences the previews are created with those settings. I guess you could lower the settings, in the browser select the images you don't need big previews, ctrl+click and 'update preview' to force create low res previews for those. After that you can put the settings back. But if you do any change to those images the previews will be updated. Certainly I don't see the point of having different previews, do some test find the settings that work best for you and keep it like that.
Turn automatic previews off and create manually the previews you need, I have a smart album with images rated 3 or more stars and I use it to select and create previews manually to those images.

My iphone has been water damaged and in the mean time ive gone back to using my old phone. But i need to get all the contacts from my iphone i had synced to my laptop, but i don't know where to find them and im not sure if ive backed them up to anything!

my iphone has been water damaged and in the mean time ive gone back to using my old phone. But i need to get all the contacts from my iphone i had synced to my laptop, but i don't know where to find them and im not sure if ive backed them up to anything!

If your contacts are synced to your computer then they are in the supported app you are syncing with.
When you set up syncing of contacts on your device, which application did you select?

Where do I use These lock object FM's (Enqueue & D? and How do I use them?

I created lock object for user defined table (zconsist). The system automatically created 2 FM's (Enquiue & Dequeue).
I created a new TCode and accessing this with mulitple users to do some updates and inserts in that above table.
I used INSERT ZCONSIST statement in 5 places in my program (4 include programs).
Where do I use These FM's? and How do I use them?
I mean before inserting which FM I need to use? after immediately what fm used?.
every insert statemnt before i need to use the respective fm? so 5 places i need to call the respective FM is it right?
thank in advance.

Hi Sekhar,
Lock objects are use in SAP to avoid the inconsistancy at the time of data is being insert/change into database.
SAP Provide three type of Lock objects.
Read Lock(Shared Locked)
protects read access to an object. The read lock allows other transactions read access but not write access to
the locked area of the table
Write Lock(exclusive lock)
protects write access to an object. The write lock allows other transactions neither read nor write access to
the locked area of the table.
Enhanced write lock (exclusive lock without cumulating)
works like a write lock except that the enhanced write lock also protects from further accesses from the
same transaction.
You can create a lock on a object of SAP thorugh transaction SE11 and enter any meaningful name start with EZ Example EZTEST_LOCK.
Use: you can see in almost all transaction when you are open an object in Change mode SAP could not allow to any other user to open the same object in change mode.
Example: in HR when we are enter a personal number in master data maintainance screen SAP can't allow to any other user to use same personal number for changes.
Technicaly:
When you create a lock object System automatically creat two function module.
1. ENQUEUE_<Lockobject name>. to insert the object in a queue.
2. DEQUEUE_<Lockobject name>. To remove the object is being queued through above FM.
You have to use these function module in your program.
check this link for example.
http://help.sap.com/saphelp_nw04s/helpdata/en/cf/21eea5446011d189700000e8322d00/content.htm
tables:vbak.
call function 'ENQUEUE_EZLOCK3'
exporting
mode_vbak = 'E'
mandt = sy-mandt
vbeln = vbak-vbeln
X_VBELN = ' '
_SCOPE = '2'
_WAIT = ' '
_COLLECT = ' '
EXCEPTIONS
FOREIGN_LOCK = 1
SYSTEM_FAILURE = 2
OTHERS = 3
if sy-subrc 0.
MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
endif.
Normally ABAPers will create the Lock objects, because we know when to lock and how to lock and where to lock the Object then after completing our updations we unlock the Objects in the Tables
http://help.sap.com/saphelp_nw04s/helpdata/en/cf/21eea5446011d189700000e8322d00/content.htm
purpose: If multiple user try to access a database object, inconsistency may occer. To avoid that inconsistency and to let multiple user give the accessibility of the database objects the locking mechanism is used.
Steps: first we create a loc object in se11 . Suppose for a table mara. It will create two functional module.:
1. enque_lockobject
1. deque_lockobject
before updating any table first we lock the table by calling enque_lockobject fm and then after updating we release the lock by deque_lockobject.
http://help.sap.com/saphelp_nw04/helpdata/en/cf/21eea5446011d189700000e8322d00/content.htm
GO TO SE11
Select the radio button "Lock object"..
Give the name starts with EZ or EY..
Example: EYTEST
Press Create button..
Give the short description..
Example: Lock object for table ZTABLE..
In the tables tab..Give the table name..
Example: ZTABLE
Save and generate..
Your lock object is now created..You can see the LOCK MODULES..
In the menu ..GOTO -> LOCK MODULES..There you can see the ENQUEUE and DEQUEUE function
Lock objects:
http://www.sap-img.com/abap/type-and-uses-of-lock-objects-in-sap.htm
http://help.sap.com/saphelp_nw04s/helpdata/en/cf/21eea5446011d189700000e8322d00/content.htm
Match Code Objects:
http://help.sap.com/saphelp_nw2004s/helpdata/en/41/f6b237fec48c67e10000009b38f8cf/content.htm
http://searchsap.techtarget.com/tip/0,289483,sid21_gci553386,00.html
See this link:
http://www.sap-img.com/abap/type-and-uses-of-lock-objects-in-sap.htm
Check these links -
lock objects
Lock Objects
Lock Objects
kindly reward if found helpful.
cheers,
Hema.

SInce i installed Lion, my desktop icons are lining up like regimented Windows icons! how do i get them to stay where i put them, like they used to do? thanks! ellen

SInce i installed Lion, my desktop icons are lining up like regimented Windows icons!
how do i get them to stay where i put them, like they used to do?
thanks!
ellen

In that case, there may be a problem with your Finder preferences or window settings.
Try removing these files, then restarting:
~/Library/Preferences/com.apple.finder.plist
~/Desktop/.DS_Store
Let me know if you're not sure how to do that.

HT203167 i have purchased 100 songs in last 2 years on itunes now i am able to find the first 50 songs i am using the original id in all my devices.i even got the invoice of my purchase where can find them all?

i have purchased 100 songs in last 2 years on itunes now i am able to find the first 50 songs, i am using the origial id in all my devices.i even got the invoice of my purshace where can find them all?
ITS NOT EVEN SHOWING UP IN PURCHASED SECTION

1. iTunes won't offer cloud downloads for songs that it "thinks" are in your library, even if it "knows" the files are missing. If you've exhaustively searched for the missing files and there is no prospect of repair by restoring to them to their original locations, or connecting to new ones, then delete that tracks that display both the missing exclamation mark and are of media kind Purchased/Protected AAC audio file. Don't hide from iTunes in the cloud when asked, close iTunes, then reopen. You can download from the cloud links or iTunes Store > Quicklinks > Purchased > Music > Not on this computer > All songs > Download all.
2. Why? Not sure, perhaps 3rd party tools or accidental key presses combined with previously hidden warning messages when trying to organize the library. There is a hint that using the feature to downsample media as it is synced to a device may also be involved, though I've not replicated it. Whatever the reason a backup would protect your media.
tt2

What are SMOUTIL1,SMOUTIL2,SMOUTIL3?where can i see?how to use them?

What are SMOUTIL1,SMOUTIL2,SMOUTIL3?
where can i see?
how to use them?
Please tell me,Thank you very much.

SMOUTIL1, SMOUTIL2, SMOUTIL3 are considered the WMD's of the CRM middleware.
If they fall into improper hands, your middleware system could be wiped out and destroyed, reaping havoc on both CRM & ERP.
Please read the all the documentation located here, before you try to use these wmd's.
http://help.sap.com/saphelp_crm40/helpdata/en/c8/93ad3a9bfd664ee10000000a114084/frameset.htm
You may want to also first read the book just published by the SAP press called the SAP CRM Middleware optimization guide, before you try doing any work with the CRM middleware.
Take care,
Stephen

I have an iMac running with Parallels. Last year, my System Updates from Apple started popping up on PC side and I cannot find a way to link them back to the Apple side of machine. Cannot update iTunes to latest version where I use it.

I have an iMac running with Parallels. Last year, my System Updates from Apple started popping up on PC side and I cannot find a way to link them back to the Apple side of machine. Cannot update iTunes to latest version where I use it.

Hello, do you mean the files end up on the PC side, or the notifications?
On the Mac side try this...
http://www.apple.com/itunes/download/

Just started using Safari, 5.1 on Win XP. Places where there used to be check boxes now have little buttons with triangles on them; clicking them seems to have no visible effect. Help!

I just started using Safari, using Safari 5.1 on Win XP. Any place where there used to be a check box, there's now a little button with a triangle on it. The triangle changes orientation as I move the mouse cursor around, but there is no visible change if I click on it. Yet it appears that I must click on it to check, or uncheck, the box; I just can't tell whether it's checked. If I can't get this to work better, I'll have to give up on Safari. Please help. (Note: there's one at the head of this thing saying "Mark this discussion as a Question - this encourages people to answer for points and helps you track answers." I clicked on it, but don't know whether it's checked or not. That's a fairly minor example.)

Can you provide an SSCCE that demonstrates this behavior?

When and where to use Dbms_Error_Code, Error_Code and SqlCode.

I have gone thru some docs and books on dev to understand error messages in Developer. After reading i am more confused reg the difference between
Dbms_Error_Code, Error_Code and SqlCode.
Can any one tell me concisely the difference and the situation where these are used.
This is my understanding so far.....
DBMS_ERROR_CODE and DBMS_ERROR_TEXT return the last Oracle Server error code and message due to an implicit DML within form application.
SQLCODE and SQLERRM return the last Oracle Server error code and message due to an explicit DML within a form application.
So why use ERROR_CODE at all?
Below is an extract from the Oracle help Docs...
When an implicit DML raises an error, it is handled with an ON-ERROR trigger using the ERROR_CODE function. This function contains the last Oracle Form error code. These errors are prefixed with FRM-.
Okay but why not just use DBMS_ERROR_CODE instead of ERROR_CODE?
Example: /*
** Built-in: DBMS_ERROR_CODE,DBMS_ERROR_TEXT
** Example: Reword certain Oracle Forms error messages by
** evaluating the DBMS error code that caused them
** Trigger: On-Error
DECLARE
errcode NUMBER := ERROR_CODE;
dbmserrcode NUMBER;
dbmserrtext VARCHAR2(200);
BEGIN
IF errcode = 40508 THEN
** Oracle Forms had a problem INSERTing, so
** look at the Database error which
** caused the problem.
dbmserrcode := DBMS_ERROR_CODE;
dbmserrtext := DBMS_ERROR_TEXT;
IF dbmserrcode = -1438 THEN
** ORA-01438 is "value too large for column"
Message('Your number is too large. Try again.');
ELSIF dbmserrcode = -1400 THEN
** ORA-01400 is "Mandatory column is NULL"
Message('You forgot to provide a value. Try again.');
ELSE
** Printout a generic message with the database
** error string in it.
Message('Insert failed because of '||dbmserrtext);
END IF;
END IF;
END;Regards
Gus

Sorry Steve as wonderful as your code example may be you are putting the cart before the horse as far as the purpose of this thread goes. I don't need guidance on HOW to use certain error functions at least not until i know WHEN i should use them and thats why i started this thread. There are 3 different sets of Oracle functions below for use in forms but not enough guidance in the docs as to when to use them for the newcomer to forms. All i need is a simple definition as to when these functions should be used appropriately in forms. The rest I will find out for myself when i start using forms properly (including the use of your wonderful code). At the moment i just want to pass the Forms exam and to have a better understanding of what i am doing.
DBMS_ERROR_CODE & DBMS_ERROR_TEXT
SQLCODE & SQLERRM
ERROR_CODE & ERROR_TEXT
I've got one person saying this....
DBMS_ERROR_TEXT and DBMS_ERROR_CODE built-ins are intended to be used in a form-level ON-ERROR trigger.
SQLCODE and SQLERRM functions are intended to be used in a WHEN OTHERS exception handler.
and another saying ...
Use error_code to handle Forms error
Use dbms_error_code to handle database error
.. then i've got your code which predominantly uses ERROR_CODE.
Then the STS test papers say this...
When an implicit DML raises an error, it is handled with an ON-ERROR trigger using the ERROR_CODE function. This function contains the last Oracle Form error code. These errors are prefixed with FRM-.
Example:
IF ERROR_CODE = 40508 THEN
MESSAGE ('Invalid insert');
RAISE FORM_TRIGGER_FAILURE;
END IF;DBMS_ERROR_CODE and DBMS_ERROR_TEXT return the last Oracle Server error code and message due to an implicit DML within form application. These errors are prefixed with ORA-.
SQLCODE and SQLERRM return the last Oracle Server error code and message due to an explicit DML within a form application. These functions must be used in the exception handler of the program unit that issues the DML command.
A little Confusing to say the least!!!
Okay, so is this correct...
SQLCODE and SQLERRM are used with explicit DML within a form application and are used in the exception handler of the program unit that issues the DML command.
When an implicit DML raises an error, it is handled with an ON-ERROR trigger using the ERROR_CODE function. These errors are prefixed with FRM-.
DBMS_ERROR_CODE and DBMS_ERROR_TEXT are also used with implicit DML within form application. These errors are prefixed with ORA-.
So why use DBMS_ERROR_CODE and DBMS_ERROR_TEXT if ERROR_CODE and ERROR_TEXT are to be used in ON-ERROR triggers and if an implicit DML error arises then whats the difference between ERROR_CODE FRM- errors and DBMS_ERROR_CODE ORA- errors? Apart from one being a form error and the other being a server error, what different things do they tell us? If an implicit DML error ocurrs would this generate ORA- and FRM- errors at the same time.
Cheers
Gus
Message was edited by:
gusora

How to retrieve comments from one OfficeTask activity and use them in another OfficeTask activity for Multi level Approval sequential Workflow

I'm designing a sequential site workflow using Visual Studio 2010 for Project Server 2010. In my case, I have following 6 stages in the workflow:
1. InitialProposal Stage
2. Approval Stage1 -- Needs approval from Approver Project Security Group Members1
3. Rejection Stage
4. Approval Stage2 -- Needs approval from Approver Project Security Group Members 2
5. Execution Stage
6. Completed Stage
Requirement is workflow should move to Approval stage2 from Approval stage1 if approved by all members of Approver Project Security Group1and it should move to Rejection Stage even if a single member rejects it.
Workflow should move from Approval Stage2 to Execution Stage if approved by all members of Approver Project Security Group2 and it should move back to Approval Stage1 on rejection by a single member of the group.
I'm using inbuilt PSWApproval content type and OfficeTask activity for creating approval task for the group members at both stages.
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My question is where exactly these comments are saved? how can we retrieve them and use them in another officetask activity? If this is not possible then what is the possible solution for meeting above mentioned business requirement?

Hi Paul,
Thanks for your suggestion.
By comments field I'm assuming OfficeTask.Comments field. Problem is, this field is always null. I tried accessing this field in CheckExitCondition activity as well as in OnTaskCompleted but in both the cases, it was null only(I wrote comments while approving
the task).
I used a code activity within OnTaskCompleted activity and following code for accessing Comments and Description fields:
public string officeComments;
public string officeDescription;
private void TaskCOmplete(object sender, EventArgs e)
CodeActivity Sender = (CodeActivity)sender;
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officeComments = ofctask1.Comments;
officeDescription = ofctask1.Description;
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Thank you

Library project errors and imports of projects using them

So this is something that I have put up with in FB for a long time now, but I decided to try doing some research today to see if there is a workaround as it is very annoying. Unfortunately I couldn't find anything.
I attempted to file a bug/feature request, but it turns out that for some unknown reason FB is the only Adobe application that gives a link to another url (http://bugs.adobe.com/flex/) and, today at least, the link is dead so I have to post here instead.
The problem is with library projects (which I love by the way). I use them a great deal and for more than just creating standalone APIs. As do many others, I like to have the core of many of my cross-platform projects in a library so that I can create other ‘harness’ projects for different runtimes and use the same bulk code. This way I can just write code in each master project that is particular to that runtime be it air or web or whatever - this is a great bit of functionality that I would really miss were it not there.
As a result of this workflow however, I am often working in the library project directly in order to update all versions of a project. The problem arises when there is an error in the library project. When this happens, all the projects reading from the library lose all linkages to the swc and as a result the problem tab fills up with hundreds of problems that don’t exist, because as far as those projects are now concerned the swc no longer exists.
Now I understand why this happens but surely FB could be made to understand what is going on and override (what I assume is) the compiler’s behaviour, and just not display these errors.
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Please save the feature that I enjoy so much by either getting FB to deal with the situation better or by fixing the crash bug so I can use ‘build automatically’ again… or god forbid… fix both!! I can dream. J
If anyone has any good tips regarding this please let me know.
Many thanks,
James

Can I then delete the project from the hard drive (as it's now in the library?) or will that delete the whole thing forever?
That depends on how you did import the projects. If your images are referenced they might still be stored in the previous projects, but if your library is managed, then it will be save to delete the projects you already imported.

If the drive my pictures were located on accidently got formatted and are no longer found on my hard drive but are still saved in my organizer on photoshop elements can I still use them?

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The only answer I have is not a pleasant one. Your photos are gone. There may be computer services that might be able to retrieve photos from a formatted drive (and they might not be able to retrieve the photos from the formatted drive). These services are usually quite expensive.
PSE has low res thumbnails. You could blow them up in the Organizer to single image view, and then do a screen capture to save these low-quality photos. You would have to do this one by one.
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My photos are in the Library, but I can't use them

Hi. I recently added a ton of photos to my library that I had in my email. They are there but I can only access them through the pictures file and cannot use them at all in iphoto. I have tried to import them into the library (even though they are there) and I get a message saying they are unreadable even though they are jpg's. So my question is, how can I get it so I can use these for slideshows etc? I mean they are on my computer in the library folder but just can't be used and don't show up unless I go through the pictures option. They aren't on the page where it says library with all the sub folders.
Hope this makes sense to someone out there because it is confusing as heck to me! I just want to be able to use these photos.
imac Mac OS X (10.4.8)

lookinforhelp:
Welcome to the Apple Discussions. Where are those image file located? It sounds like they are located somewhere inside the iPhoto Library folder and iPhoto will not import any file located there. So move them to the Desktop and import from there. Never put any file inside the iPhoto Library folder via the Finder or move, rename or edit any file or folder via the Finder.
Do you Twango?
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How to use KM APIs, Can we use them in Standalone J2ee Application

Hi Experts,
I got KM APIs.
I need to use them to access the KM Repository Content.
I m a newbie in SAP KM.
Can anyone help me to use KM APIs.
For Eg:
com.sapportals.portal.security.usermanagement.IUser user =
IResourceContext resourceContext = new ResourceContext(user);
RID rid = RID.getRID("/etc");
try {
IResource resource = ResourceFactory.getInstance()
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if( resource != null ) {
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} else {
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catch( ResourceException e ) {
// problem while retrieving the resource
System.out.println(
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                    + ": " + e.getMessage()
How will i get the IUser populated?
Can i use KM APIs from a standalone J2EE application?
Can i Populate IUser in standalone J2EE application's Servlet?
Please help me out.
Waiting for reply
-pankaj

Hi Prem,
Can u tell me how to deploy a war file on to the SAP J2EE server?
I know how to deploy on Tomcat Server, but dont have any experience abt SAP J2EE server.
Does SAP J2EE server also have some Webapp directory like TOMCAT where we have to put our WAR File?
Or to Deploy a WAR File in SAP J2EE server is different, if yes then wats the procedure to do that?
And can i access the KM APIs in SAP J2EE Server?

Generics - where to use them?

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