Reference flag and synchronization

Hi,
I created a view object based on 3 entity objects. There is an association between entity A and B and another one between entity B and C. On the view object editor:
- for entity A, updatable is checked, Reference is not.
- for entity B, updatable is not checked, Reference is.
- for entity C, updatable is not checked, Reference is.
Now if, in the view object through a GUI, I set the attribute linked to the attribute at the source of the association between entity A and B to null, in the view object, all the value linked to the entity object B are set to null.
This is fine.
My problem is that the value in entity C are not synchronized. In my example, the value linked to entity C should be set to null instead of staying the same as before the modification. Is there an additional setting I'm suppose to make to have my entity C be synchronized with my entity B ?
Btw, I'm using jdeveloper 10.1.3
Thanks
Pascal

No
a specific photo can only exist in one event
If you duplicated the photos in the source event then flagged the new one (actually either one) you could do taht - you would, of course double the storage used for those photos winch there are now two of each - and any edits, =delete, etc would only operate on the one you did it to leaving the other copy alone (maybe what you intend?)
LN

Similar Messages

Diff b/w reference type and elementary type

hi all
can any one what is the diff b/w reference type and elementary type in data element ....
thanks
lokesh

The data type attributes of a data element can be defined by:
Specifying a domain whose attributes are copied by the data element.
Specifying a build-in type where the data type, number of places, and possibly decimal places can be directly specified.
Specifying a reference type, i.e. reference to a class, an interface, a type defined in the Dictionary, a built-in type, or a generic reference to ANY or DATA.
In the maintenance screen you can set the option you require by setting the appropriate flag (domain, built-in type, reference type) and filling in the corresponding input fields.
A reference type is a reference to another type. There are the following kinds of reference types:
Reference to a class or an interface
Reference to a type defined in the Dictionary
Generic reference to ANY, OBJECT, or DATA
Reference to a built-in Dictionary type with specification of the length and possibly also the decimal places
You can use a reference type to define the data type properties for a data element, or for typing the component of a structure or the line type of a table type.
In the field Referenced type, enter the name of a class, an interface, the generic references DATA, OBJECT, ANY, or the name of a type defined in the Dictionary. If the reference type is to be a predefined Dictionary type, choose the reference to the predefined type. Enter the number of characters and, if required, the number of decimal places.
where as
The data class describes the data format at the user interface.
If a table field or structure field or a data element is used in an ABAP program, the data class is converted to a format used by the ABAP processor. When a table is created in the database, the data class of a table field is converted to a corresponding data format of the database system used.
You can find a detailed description of the data classes allowed in the ABAP Dictionary in Overview of the Data Classes.

Environment open flags and multithreading

Do I actually need to create an environment explicitly if I want to read only from a database in a multithreaded program (no other process, no write operations)? I don't need to use DB_INIT_LOCK as there is no thread writing to the database. And I don't need to use DB_INIT_MPOOL as there is no other process using the very same database. As the database is read-only the open flags DB_INIT_LOG, DB_INIT_TXN and DB_RECOVER don't provide any benefit either. Is this all correct? I don't need to use DB_THREAD either (which I found in the documentation of DbEnv)?
Boris

LaurenFoutz wrote:
You are correct. Using XmlManager without an environment will automatically create an environment that can support multithreaded access (but not multiprocess). So for your multithreaded single-process read only application an XmlManager without an explicit environment should be sufficient.I started to test some code. Unfortunately it always crashs if I use more than one thread. I get different error messages when it crashs - here are a few:
{font:Courier}BDB XML: page 0: illegal page type or format
BDB XML: PANIC: Invalid argument
BDB XML: assert failure: ..\..\db-4.6.21\db\db_cam.c/92: "F_ISSET(dbc, DBC_ACTIVE)"
BDB XML: PANIC: fatal region error detected; run recovery{font}
{font:Courier}BDB XML: assert failure: ..\..\db-4.6.21\mp\mp_alloc.c/564: "(bhp == first_bhp)? priority == last_priority : priority >= last_priority"{font}
{font:Courier}BDB XML: test.bdbxml: more pages returned than retrieved
BDB XML: PANIC: Permission denied
BDB XML: PANIC: fatal region error detected; run recovery{font}
I still have to debug the code to find out if I am doing anything wrong. But are there any known issues that it makes sense if I try to use some flags and maybe create the environment explicitly? Currently I only use DB_RDONLY to open the container.
Boris
PS: I just saw that the API reference contains a flag DB_THREAD. If I open the container with DB_THREAD though I get another error message:
{font:Courier}BDB XML: environment not created using DB_THREAD{font}
I'm a bit confused now: Either DB_THREAD is not required for thread-safe access or an environment must be created explicitly in order to use DB_THREAD?
Edited by: Boris Schaeling on Jul 31, 2009 2:11 AM

VO with reference flag indirect relation = EntityImpl not retrieved?

Hi,
JClient 10.1.2
I have a ViewObject VOabcd based on 4 entities:
EntityA,EntityB,EntityC and EntityD.
ViewObject VOabcd is part of package 2.
EntityA is updateable and is part of package 2.
EntityB,EntityC and EntityD have reference flag set.
EntityB, EntityC and EntityD are part of package 1.
EntityA has foreign key association with EntityB: (*,1) relation.
EntityB has foreign key association with EntityC: (*,1) relation.
EntityB has foreign key association with EntityD: (*,1) relation.
Only the fields of EntityA are updateable so no set methods for attributes of the entities in the VO.
When I set the foreign attribute to EntityB all fields of EntityB are displayed automatically but the attributes of EntityC and EntityD are not retrieved as expected?
I have no set methods so I can't retrieve those attributes manually.
Your help is requested.
Thanks
Frederic
For your info, a VO in package 1 based on the same relations of EntityB,EntityC,EntityD works as expected.
For your info, extract of VO.xml file:
<EntityUsage
Name="Wevent"
Entity="com.photoswing.model.web.Wevent" >
<DesignTime>
<Attr Name="_EntireObjectTable" Value="false" />
<Attr Name="_queryClause" Value="true" />
<Attr Name="_queryWhere" Value="((Wevent.LAB_EVENT_TYPE_ID = LabEventType.LAB_EVENT_TYPE_ID) AND (LabEventType.FILM_TYPE_ID = FilmType.FILM_TYPE_ID) AND (LabEventType.PAPER_QUALITY_ID = PaperQuality.PAPER_QUALITY_ID) )" />
</DesignTime>
</EntityUsage>
<EntityUsage
Name="LabEventType"
Entity="com.photoswing.model.lab.LabEventType"
Association="com.photoswing.model.web.WeventLabEventTypeAssociation"
AssociationEnd="com.photoswing.model.web.WeventLabEventTypeAssociation.LabEventTypeWevent"
SourceUsage="com.photoswing.model.web.WeventEditVO.Wevent"
ReadOnly="true"
Reference="true" >
<DesignTime>
<Attr Name="_EntireObjectTable" Value="false" />
<Attr Name="_queryClause" Value="false" />
<AttrArray Name="_srcAttributes">
<Item Value="com.photoswing.model.web.Wevent.LabEventTypeId" />
</AttrArray>
<AttrArray Name="_dstAttributes">
<Item Value="com.photoswing.model.lab.LabEventType.LabEventTypeId" />
</AttrArray>
</DesignTime>
</EntityUsage>
<EntityUsage
Name="FilmType"
Entity="com.photoswing.model.lab.FilmType"
Association="com.photoswing.model.lab.LabEventTypeFilmFkAssoc"
AssociationEnd="com.photoswing.model.lab.LabEventTypeFilmFkAssoc.FilmTypeLabEventType"
SourceUsage="com.photoswing.model.web.WeventEditVO.LabEventType"
ReadOnly="true"
Reference="true" >
<DesignTime>
<Attr Name="_EntireObjectTable" Value="false" />
<Attr Name="_queryClause" Value="false" />
<AttrArray Name="_srcAttributes">
<Item Value="com.photoswing.model.lab.LabEventType.FilmTypeId" />
</AttrArray>
<AttrArray Name="_dstAttributes">
<Item Value="com.photoswing.model.lab.FilmType.FilmTypeId" />
</AttrArray>
</DesignTime>
</EntityUsage>
<EntityUsage
Name="PaperQuality"
Entity="com.photoswing.model.lab.PaperQuality"
Association="com.photoswing.model.lab.LabEventTypeQualityFkAssoc"
AssociationEnd="com.photoswing.model.lab.LabEventTypeQualityFkAssoc.PaperQualityLabEventType"
SourceUsage="com.photoswing.model.web.WeventEditVO.LabEventType"
ReadOnly="true"
Reference="true" >
<DesignTime>
<Attr Name="_EntireObjectTable" Value="false" />
<Attr Name="_queryClause" Value="false" />
<AttrArray Name="_srcAttributes">
<Item Value="com.photoswing.model.lab.LabEventType.PaperQualityId" />
</AttrArray>
<AttrArray Name="_dstAttributes">
<Item Value="com.photoswing.model.lab.PaperQuality.PaperQualityId" />
</AttrArray>
</DesignTime>
</EntityUsage>

I found the solution/problem.
The foreign key attributes of EntityB to EntityC and EntityD were not in the VO.
When creating a new row in JClient, in order to display automatically the attributes of a referenced entity when entering the foreign key attribute the following is required:
- the reference flag must be set
- the foreign key must be in the VO
- the primary key of the referenced Entity must be in the VO (automatically added by the VO editor).
My question:
When you shuffle an attribute of a referenced Entity the PK attributes are automatically added.
Why aren't the foreign key attributes automatically added?
Thanks
Frederic

BADI to get GR done flag , Final Invoice flag and Delivery completed flag

Hi all,
An Idoc needs to be triggered for PO line items to indicate different flags. As soon as MIGO or MIRO is done for PO line item, I have to check three flags namely GR done flag , Final Invoice flag and Delivery completed flag and send information of these flags as set.
I want to know which BADI or User exit will give information to indicate that either of one or all above flags are set for PO line item as soon as MIGO or MIRO is used.
Thanks in advance,
Madhura

HI,
When Purchase order is created with reference to contract, system carry
out the check whether Document date of PO should be within contract
"validity start" and "vaidity end" date. If document date is outside
the "validity start" and "validity end" date of PO, message 06 040
"Validity period of contract does not start until &" or message
06 041 " Validity period of contract expired on &" is raised.
Same check is also carried out during any change in PO (txn ME22N).
Please use one of following option to close the PO.
1. Change the category of message 06041 as warning in customization.
Txn OLME.
Environment Data -> Define Attributes of System Messages ->System
Messages
2. Change the validity end date in contract and close the Purchase order. Validity end date can be reverted.
BR
Nadia Orlandi

Overlay and synchronize video

Hello,
Does anyone know, how to overly and synchronize 2 or more videos of athletes, for example alpine skiers, using Premiere Pro? You can see that on the TV sometimes, where 2 racers are put into one track over each other and you can compare their rides? They are using special technology on the TV, probably Dartfish. But I hope somebody has some idea how to do it in Premiere? I have put one video over the second and set the opacity to 50%. Then I moved the upper video and adjusted its size, so that the gates (the skiers were at) matched. I created keyframes for couple of gates and for each of them I repeated the same and hoped Premiere would do the rest. But the result isn't good, the skiers drive away just a moment after leaving the gate. Any tips? Thanks. Ivan

Just for future reference, should anyone be looking at this thread for more information:
This link has a table with all major DIAdem features and what type of license (Base, Advanced or Professional) is required to use these features:
http://www.ni.com/diadem/buy/
The Professional license adds
3D model data mapping
GPS map layouts
to the features already present in the Advanced version (including video synchronization).
This page has a very detailed list of features, with more in depth descriptions and screen shots:
http://sine.ni.com/ds/app/doc/p/lang/en/id/ds-263#view.base
Maybe this is helpful to someone ...
Otmar
Otmar D. Foehner
Business Development Manager
DIAdem and Test Data Management
National Instruments
Austin, TX - USA
"For an optimist the glass is half full, for a pessimist it's half empty, and for an engineer is twice bigger than necessary."

Excel Get ActiveX References.vi and closing references -- grrr

I'm new to ActiveX stuff, but eager to learn!
The "grrr" in my Subject line is a reference to how I feel about LabVIEW's documentation from time to time. I'm a dinosaur who came from text-based programming, and did a fair amount of C coding, so sometimes with LabVIEW I'm left with this awful feeling in the pit of my stomach like, "Good grief! How much memory must LabVIEW be hogging up in the background when I use this vi?" or "What happens to those variables (wires) in that subVI when it completes but doesn't close? What are their statuses when I come back in the next time?" or "What if I put a lot of elements into that array the first time and then started from element zero the second time and just put in a few? What has happened with the memroy that was allocated when there were a lot of elements?"
Today I'm stewing about this "Excel Get ActiveX References.vi," and what happens to the "ActiveX references" it generates each time I call the subVI in which "Excel Get ActiveX References.vi" lives. I think that at least one of the "ActiveX references" it generates when I call it is of the type Excel._Application. Then there appears to be an Excel._Workbook, and others. You see, I've used "Excel Easy Report.vi" to put some data into an Excel spreadsheet, and I want to tell Excel to do a "Save" on the open spreadsheet. I think ActiveX is the (a) right way to do that, so I'm wading into the ActiveX fray... But this "Excel Get ActiveX References.vi" says in its help file, "Do not close ActiveX references opened with the Excel Get ActiveX References VI. References must remain open until the report is closed. Otherwise the error 3001 will occur." Well, these Excel workbooks that get created by my VI could well stay open until after my LabVIEW VI terminates!
So (finally), here are some of my quesitons:
1) When I go through my subVI once, pointing to one workbook, I'll get one set of references "created" or "opened" or whatever you call it when ActiveX references spring into existance. Now, when I exit the subVI, is it going to automatically try to "close" those ActiveX references? I don't suppose so, since subVI's stay in memory until the calling VI closes.
2) Now, I come back into my subVI a second time. New workbook gets created, so I get new references. Ok, fine. Uh oh! What happened to those old references? I suppose that if I didn't somehow save them off, I've probably lost the ability to get them back (maybe I'm wrong, but I don't need them back), but is LabVIEW going to "close" those old references (from previous times through the subVI) because I can't get to them anymore? Won't that cause the dreaded error 3001? If LabVIEW is not going to "close" them, what in tarnation happens to them (the old C programmer in me creeping back out)?? Now it's some oddball, orphaned reference, floating out there, hogging memory, waiting to make something crash intermittently and be a debugging nightmare?
3) Now, here's the real scary one. I think I might dodge the "error 3001" bullet in questions 1) and 2), but now let's say the user closes my LabVIEW application while Excel is still open. All those workbooks are still open. Presumably, all those ActiveX references I was not supposed to close are still open. I really hope that LabVIEW is decent enough to close/erase/delete/blow-away (whatever the right word is) all those ActiveX references which were opened/created by "Excel Get ActiveX References.vi" when my program terminates. But, oh no! Won't the error 3001 come along then? I suppose I can just dump it in the shutdown error handling.
Well, thanks for reading my novel. I don't know what can be done with LabVIEW documentation to make it more satisfying to folks like me, but perhaps someone can weigh in on all my ActiveX questions here.
Thank you in advance,
Steve Brady
Solved!
Go to Solution.

You need to close EVERY ActiveX reference you open. If you don't you'll end up with some Excel processes running even after LabVIEW exits. You can see them in Task Manager.
I, personally, don't like the LabVIEW Report Generation Tool Kit for working with Excel. I don't think it's flexible enough. I have a growing library of VIs that I've written that open, manipulate, and close Excel. Some references I pass from VI to VI and some I close right after I use them. It all depends on what I'm doing. If I want to enter read or write data from/to a certain range I'll get the range reference, read or write the data, then close it right away because I have no use for it any more. On the other hand, when I open Excel or a Workbook I keep the reference until I'm done, which could be later in the program.
1) When I go through my subVI once, pointing to one workbook, I'll get one set of references "created" or "opened" or whatever you call it when ActiveX references spring into existence. Now, when I exit the subVI, is it going to automatically try to "close" those ActiveX references? I don't suppose so, since subVI's stay in memory until the calling VI closes.
2) Now, I come back into my subVI a second time. New workbook gets created, so I get new references. Ok, fine. Uh oh! What happened to those old references? I suppose that if I didn't somehow save them off, I've probably lost the ability to get them back (maybe I'm wrong, but I don't need them back), but is LabVIEW going to "close" those old references (from previous times through the subVI) because I can't get to them anymore? Won't that cause the dreaded error 3001? If LabVIEW is not going to "close" them, what in tarnation happens to them (the old C programmer in me creeping back out)?? Now it's some oddball, orphaned reference, floating out there, hogging memory, waiting to make something crash intermittently and be a debugging nightmare?
3) Now, here's the real scary one. I think I might dodge the "error 3001" bullet in questions 1) and 2), but now let's say the user closes my LabVIEW application while Excel is still open. All those workbooks are still open. Presumably, all those ActiveX references I was not supposed to close are still open. I really hope that LabVIEW is decent enough to close/erase/delete/blow-away (whatever the right word is) all those ActiveX references which were opened/created by "Excel Get ActiveX References.vi" when my program terminates. But, oh no! Won't the error 3001 come along then? I suppose I can just dump it in the shutdown error handling.
1) No, LabVIEW will NOT close those references. You need to make sure that happens.
2) You can save the references in a functional global or use a class but if you're not going to save them close them as soon as you're done with them.
3) Your user should not be able to close your LabVIEW application without it going through the shutdown routine you've created for your program. The ABORT button should never be exposed to the user and you should capture and discard the panel close event so your program ALWAYS shuts down is an orderly fashion. If you don't you will have fragments of Excel hanging around in your operating system and will have to kill those processes using Task Manager. That should only be a problem during development, not once deployed.
I used to program in C and Assembly many moons ago. You should have seen my first LabVIEW code. I go back and look at it just so I can see how far I've come in the last 12 years. I feel your pain.
Kelly Bersch
Certified LabVIEW Developer
Kudos are always welcome

A bug with flags and active view? Or is it a (bad) feature?..

As I mark an image in a folder view as flagged and then switch to a collection view and look on the same image, it's not flagged.
I expect, that information about marking the image as flagged remains on that image, not on a current active view.

It's as designed - Flags are local to a Folder/Collection.
>Or is it a (bad) feature?
It depends - some think it's a great and others hate it with a passion.

Reference field and table for AUFK for F4 help in alv.

Hi All,
   I need to put F4 help on ALV for order no (AUFK) what is the reference field and table for that?
i tried giving field as aufk and table as ccss but its not working.
   ls_fcat-ref_field = 'AUFNR'.
    ls_fcat-ref_table = 'CCSS'.
Thanks & Regards,
Ruchi Tiwari

Hi,
Try this.
Set the f4 help for the field in the fieldcatalog
ls_fcat-f4availabl = 'X'.
1. Create a event of ONF4 for the alv grid.
2. Set the event handler.
3. Append the field for the F4 help in the internal table and call the below method
    CALL METHOD g_mprn->register_f4_for_fields
    EXPORTING
      it_f4 = i_f4.
4. create a class definition and implementation
    refer sample pgms (BCALV_F4, BCALV_GRID_EDIT_DELTA and BCALV_GRID_EDIT)
Hope this may be helpful.
Regards,
Sharin.

Flags and colors not taking (seems like a bug to me)

I'm seeing a bit of an issue I am not sure I understand.
I have a folder called
"creative" with four albums in it:
1
2
3
4
If I select all the images in the folder and TAG them and add a ORANGE COLOR these tags and colors show up on all the images in the Folder.
However, /some/ of the images in some of the folders have images that are showing up without the Orange Color and in some case there are images without the Flag or the Orange Color.
This is so confusing it seems like a bug to me.
What am I missing?

Hi. The first image is where I selected all the images and FLAGGED AND COLORED THEM.
The next two images show SUB-Albums in this folder where there are images that are either not flagged or not colored...
http://dl.dropbox.com/u/15285654/all%20colored%20and%20flagged_FOLDER.png
http://dl.dropbox.com/u/15285654/not%20flagged_ALBUM.png
http://dl.dropbox.com/u/15285654/not%20colored_ALBUM.png
Is this something I am not understanding or not doing correctly?
Thank you!

My computer keeps defaulting from a GB format to US format keyboard with a US flag in the top bar. How do I get it to go back to a GB flag and stay with a GB flag?

My computer keeps defaulting from a GB format to US format keyboard with a US flag in the top bar. How do I get it to go back to a GB flag and stay with a GB flag?
This only started 2 days ago.
I have seen much on line as this seems to be a common problem, however none of the suggestions posted seem to work.

Thanks Drew,
On clicking the US flag I had previously then unchecked the US box. It has rechecked itself, and I have unchecked it again. The GB English remains checked.
The flag icon has now gone completely from the top bar (just replaced with character and keyboard viewer) -but that's fine. That's different to previous attempts to fix the issue.
Hopefully now I will remain able to type a £ sign on the keyboard rather than get the criss-cross symbol. It may well default back in about an hour (which is what has been happening since this started 2 days ago). If it does I'll come back on here. Many thanks in the mean time for your help.

Key Figure Reference table and fields

I am getting the following error:
/BIC/CSSMMIMI1-/BIC/KFMI_LCHF (specify reference table AND reference field)
I am aware that it is asking me to put a reference table and field for the field in the structure.
However, what I am not sure about is should I do this action from SE11 or is there a program or other method which would be more suitable (this is not business content)?
Thanks

Hi Edwin,
Thanks for that, the currency type and quantity type are hard coded in the key figure for most of the key figures apart from one, i.e for the quanity I hard code PCS
From RSD2 I just check the repair option is that correct

Lightroom 6 is up and running. Upgraded from LR5. However I want to change the file name to be more generic, e.g., description in LR5 references LR5 and I want to change that to just John G's LR Catalog/Library.lrcat. How can I accomplish this without

Lightroom 6 is up and running. Upgraded from LR5. However I want to change the file name to be more generic, e.g., description in LR5 references LR5 and I want to change that to just John G's LR Catalog/Library.lrcat. How can I accomplish this without fouling everything up?

Ok, well you'll need to do something like this. Now this part is a little dependent on your database server:
       try {
            Class.forName("org.gjt.mm.mysql.Driver").newInstance();
            Connection c = DriverManager.getConnection(
                                                       "jdbc:mysql://{database-server}/{database-name}:3306?user={username}&password={password}");
            Statement Stmt = c.createStatement();
            int count = Stmt.executeUpdate(cmd);
            if(count>0) {
                 System.out.println("count: " + count);
        } catch (Exception e) {
            e.printStackTrace();
    }That was some sample code for a MySQL database.
Note that the applet can only contact the server that is was loaded from, so you might want to do a getCodeBase() or something like that to get the server address.
Hope this is helpful.

Problems with creating reference system and user mapping in EP

Hi@all,
we have deployed Support Package Stack 25 in our portal. After that, the UWLJWF Administration was not available anymore. We get Portal Runtime Error. We habe resolved this error!
In the UME Administration in the System Administration --> System Configuration --> UME Configuration --> User Mapping tab
there was a message saying that CTS was non-existent. I changed the Reference System to (No reference system) and the UWL Admin page is working now!
But now, the SSO to our 3rd Party System is not possible anymore!
I have created an new system alias but i cannot see it in the User Mapping tab. How is it possible. I found no documentation?
Thany you and best regards
Juergen

I am using EP7 Stack 11 and unfortunately the only options I have are:
user
admin
admin,user
It is currently set to admin, user and does not seem to work!
Phil
Message was edited by:
Phil Wade

The truth about objects, references, instances and cloning (Trees and Lists

Hello
As a few of you may have know from my postings over the past few weeks, ive been building my first real java ap and trying to learn along the way, hitting a few snags here and there.
One main snag i seem to have been hitting a fair bit is objects and instances, im kinda learning on how they work and what they mean but as a php programmer it seems to be very different.
as pointed out to me if you have objectA=objectB then in php you have two objects that share the same value but in java you have still one object value and one object pointing to the value.
sooo my first question is
if i have this
Object objA=new Object()
Object objB=objA()then object A creates a new memory allocation for the object data right? and object B is simply a reference to the object A memory allocation right?
so therefore there is no instance of objectB? or is there an instance of object B but it just takes up the same memory allocation as object A?
anyway, what is the point of being able to say objB=objA what can that be used for if not for making a copy of an object (i understand now that it doesnt copy an object)
My second question (which i think i actually understand now, but im posting it to see if the answers may help others)
If i have a List structure (e.g. arraylist) then when i add a datatype such as a treemap does it not add the changed treemap, ill try and explain with code
ArrayList mylist=new ArrayList()
Treemap myTree=new Treemap()
myTree.put("hello","howdy");
myTree.put("bye","cya");
mylist.put(myTree);
System.out.println(mylist.toString());
myTree.put("another","one");
mylist.put(myTree);
System.out.println(mylist.toString());now to be honest ive not actually tried that code and it may actually procude the right results, but from my experience so far that similar sort of thing hasnt been working (by the way i know the above code wont compile as is :p)
anyway what i assume is that will output this
[Hello,howdy,bye,cya] <<this is the first system out
[Hello,howdy,bye,cya,another,one <<this is the second system out
Hello,howdy,bye,cya,another,one] <<this is the second system out
where it should produce this
[Hello,howdy,bye,cya,
Hello,howdy,bye,cya,another,one]
Why when I update the treemap does the arraylist change, is this because the thing that is being put in the array list is infact not an object but simply a reference to an object?
thanks for everyones help so far :)

as pointed out to me if you have objectA=objectB then
in php you have two objects that share the same value
but in java you have still one object value and one
object pointing to the value.Some years ago, I built a small website managing data saved in an XML file using PHP. Being used to Java, I used an OO approach and created classes managing data structures and having setter/getter methods. The fact that PHP did actually create a copy of any object being passed as and argument made me crazy. This way, I wasn't able to reach the same instances from several different places in my code. Instead, I had to put a certain operator ("&" I think) before any reference to force PHP not to make a copy but pass the reference. I also found a note on the PHP site saying that copying was faster than passing the reference, which I actually couldn't believe. If I'm not wrong, they changed the default behaviour in PHP5.
if i have this
Object objA=new Object()
Object objB=objA()then object A creates a new memory allocation for the
object data right? and object B is simply a reference
to the object A memory allocation right?The statement "new <Class>" allocates memory. The reference itself just takes up a few bytes in order to maintain some administrative data (such as the memory address). References are basically like pointers in C, though there's no pointer arithmetics and they can't point to any arbitrary place in memory (only a legal instance or null).
so therefore there is no instance of objectB? or is
there an instance of object B but it just takes up
the same memory allocation as object A?There is an instance of objectB, but it's just the same instance that objectA is pointing at. Both references objectA and objectB contain the same memory address. That's why they'd produce a result of "true" if compared using the "==" operator.
anyway, what is the point of being able to say
objB=objA what can that be used for if not for making
a copy of an object (i understand now that it doesnt
copy an object)Sometimes you don't want to make a copy, as 1) it consumes more memory and 2) you'd lose the reference to it (making it more difficult to tell what instance is actually accessed). If there was no way to pass a reference to an object into a method, methods wouldn't be able to affect the original instance.
Why when I update the treemap does the arraylist
change, is this because the thing that is being put
in the array list is infact not an object but simply
a reference to an object?The ArrayList doesn't change at all. It's the instance that's being changed, and the ArrayList has a reference to it.

Reference flag and synchronization

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