What happens in jvm

Hi,
I want to know what happens in jvm.I have heard that java compiler compiles java source code to a java instruction set called bytecode. What happens when this bytecode is executed. Does it get converted to assembly. Please tell me where i can get more help on this matter.
Thanks.
chamal.

Bytecodes may be either interpreted or compiled into machine code as it is executed. Very old JVMs only interpreted the bytecodes, all newer JVMs use one for of just-in-time-compilation to native machine code at runtime.
Chuck

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What happen when i compile a java prog.

I, to an extend know how to code using java. However I don know what really happens after compiling a java prog and what happens when i run it.. what is JVM, JDK, JIT etc., means.. What is a class file and a jar file and a war file.. I'm confused.. ANy help is really appreciated..
Thanks in advance..
regards.

Java source is compiled into "portable byte code" (a class file).
The JVM (virtual machine) interprets the "portable byte-code" into "machine instructions"... The actual instructions may vary from platform to platform, but the contract is they will allways have the same effect.
JIT stands for "Just In Time"... as usually means "JIT-compiler"... which is fancy pants name for an interpreter.
Google will tell you more.

What happens when an exception occurs at finalize method ?

What happens when an exception occurs at the time of cleaning objects in finalize methods?
Will program crashes?

1.) Why don't you try it? You can simply throw your own exception.
2.) For this kind of questions the JVM specification is a good resource, for your concrete problem the chapter about finalization might be interested (look for the sentence starting with "If an uncaught exception ...").

What happens when you get Error 1905??

ERROR 1905 MODULE C:/PROGRAM FILES/ITUNES/ITUNESMINIPLAYER.DLL
FAILURE TO UNREGISTER
HRESULT-2147200472
CONTACT YOUR SUPPORT PERSONNEL
Okay...so what do I do? After this it goes to "stopping services", but says it is unable to do that. Then when I open I-tunes it says that the part of the program where the computer connects to the ipod was not installed correctly. this is soooo frustrating. my brother's had an ipod shuffle for about 2 years so itunes was already installed. i was just trying to update it so my ipod video could be read.
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Sorry no but here is some info anyway,
We increased MaxPermSize from 192 to 512
We also increased min and max JVM Heap size to 768 and 2048 respectively.
Since then I think we have not experienced this problem more than once.
We also have one server with the default parameters and it seems to work fine.
I believe that size, and number of simultaneous request/responses have an impact on this.
We will now install the latest updates and after that decide whether to start logging jvm activities or not.
Best regards
Lennart
Från: Neo Rye [email protected]
Skickat: den 28 november 2012 06:44
Till: Lennart Risfelt
Ämne: what happens when you get a "PermGen space null" error?
Re: what happens when you get a "PermGen space null" error?
created by Neo Rye<http://forums.adobe.com/people/Neo+Rye> in ColdFusion - View the full discussion<http://forums.adobe.com/message/4879436#4879436

What happens when you get a "PermGen space null" error?

We have resently installd CF 10 64 bit om three new windows 2008 R2 servers.
One of them keeps generating an error "PermGen Space null" when processing CF script files.
There is nothing special about the scripts resulting in error
we have tried to increse Maxpermsize from 192m to 768m but that had no effect.
the other two servers seems to bee doing fine.
Any ideas what to do?

Sorry no but here is some info anyway,
We increased MaxPermSize from 192 to 512
We also increased min and max JVM Heap size to 768 and 2048 respectively.
Since then I think we have not experienced this problem more than once.
We also have one server with the default parameters and it seems to work fine.
I believe that size, and number of simultaneous request/responses have an impact on this.
We will now install the latest updates and after that decide whether to start logging jvm activities or not.
Best regards
Lennart
Från: Neo Rye [email protected]
Skickat: den 28 november 2012 06:44
Till: Lennart Risfelt
Ämne: what happens when you get a "PermGen space null" error?
Re: what happens when you get a "PermGen space null" error?
created by Neo Rye<http://forums.adobe.com/people/Neo+Rye> in ColdFusion - View the full discussion<http://forums.adobe.com/message/4879436#4879436

What happens when Weblogic starts?

I need help about what happens when weblogic is starting.
My computer gets freezed having CPU 100% for a couple or more minuts and putting
-verbose:class it show this messages.
Thanks.
[Loaded weblogic.management.deploy.slave.VersionTracker]
[Loaded weblogic.management.deploy.slave.Semaphore]
[Loaded weblogic.management.configuration.FileT3MBean]
[Loaded weblogic.transaction.internal.ServerTransactionManagerImpl$MigratedTLog]
>>>>>> !!!!!! wait for several minuts !!!!!! <<<<<<<<<<<<<<<
[Loaded weblogic.management.descriptors.application.weblogic.JdbcConnectionPoolMBean]
[Loaded weblogic.application.ApplicationInfo]
[Loaded weblogic.j2ee.ApplicationLifecycleListener]
[Loaded weblogic.j2ee.Application]
[Loaded $Proxy81]

"F.Lorent" <[email protected]> wrote in message news:407e3ab7$[email protected]..
Sorry, sorry I have typed too fast?
My environment is
Weblogic 7 SP2, jvm 131_06
WindowsNT 4.0 SP6, Pentium 4, 1.8ghz 256MBThat's strange. Do you have an anti-virus installed by chance?
Regards,
Slava Imeshev
What's your environment? OS, weblogic version?
Slava
"F. Lorent" <[email protected]> wrote in message news:[email protected]..
I need help about what happens when weblogic is starting.
My computer gets freezed having CPU 100% for a couple or more minutsand putting
-verbose:class it show this messages.
Thanks.
[Loaded weblogic.management.deploy.slave.VersionTracker]
[Loaded weblogic.management.deploy.slave.Semaphore]
[Loaded weblogic.management.configuration.FileT3MBean]
[Loaded weblogic.transaction.internal.ServerTransactionManagerImpl$MigratedTLog]
!!!!!! wait for several minuts !!!!!! <<<<<<<<<<<<<<<[Loaded weblogic.management.descriptors.application.weblogic.JdbcConnectionPoolMBean]
[Loaded weblogic.application.ApplicationInfo]
[Loaded weblogic.j2ee.ApplicationLifecycleListener]
[Loaded weblogic.j2ee.Application]
[Loaded $Proxy81]

What happens on iCloud (ex. contacts) when multiple family members use the same Apple ID?

What happens on iCloud when multiple family members use the same Apple ID? For example if we all choose to use iCloud for contacts, are they all merged together? We use the same Apple ID so we can use find my iPhone to keep track of the whole family.

Of course if you are both connected to the same iCloud account you have the same contacts - what did you expect?. The contacts live on the server and are read from there by the devices; so as you've both managed to sync your contacts up to iCloud they are now inextricably mixed. You can only delete your contacts by deleting individual ones, and doing that will delete them from your phone as well.
You can only unravel this by
1. In the iCloud contacts page at http://icloud.com, select all the contacts, click on the cogwheel icon at bottom left and choose 'Export vCard'.
2. Sign out of System Preferences>iCloud
3. Create a new Apple ID and open a new iCloud account with it for your own use.
4. Import the vCard back into the iCloud contacts page.
5. Go to http://icloud.com and sign in with the original ID. This is now his ID. Work through the contacts individually deleting the ones you don't want him to have. When done sign out and advise him to change his password.
6. Go to the new iCloud account and delete his contacts individually.
Of course if you have also been syncing calendars and using the same email address there are problems with doing this.

What happens to the open item in bsid table when it is cleared

hi experts,
i have a doubt about open and cleared items of accounting documents. as we know open items of customers are stored in bsid and cleared ones in bsad. For suupose, an open item is closed ina particular period then what happened to the entry in bsid and bsad table. an entry regarding is stored in bsad (cleared),and what happens to the entry in bsid, still it will be there or removed from it.

Hi,
When ever we clear the document(Complete payment) that document will be moved to BSAD table. Other wise it will remain in BSID.
If u are making partial payment then all the partial payment documents along with original document will be stored in BSID till u made the complete payment for that invoice.
Assumption is u have to give all partial payment documents made for particular invoice item while u are making complete payment in F-28 transaction. So that these partail payment documents will also be cleared while making complete payment and moved to BSAD table.
This trasaction can be used for both partial and complete payments.
Irrespective of complete or partial payments made all the documents will remain stored in BKPF and BSEG tables.
BSID and BSAD are index tables to address performance issues with BKPF and BSEG tables.
So all open and cleared documents will be there in BKPF and BSEG tables.
All cleared documents will be there in BSAD table.
Alll open documents will be there in BSID table.
Hope it is clear.
Thanks,
Vinod.

I found My iPhone contacts on my friends Iphone we both have 4s! But we use the same apple ID and ICloud ID! How can undo what happened? all my private stuff is now on his phone!!! help me plz!!?

I found My iPhone contacts on my friends Iphone we both have 4s! But we use the same apple ID and ICloud ID! How can undo what happened? all my private stuff is now on his phone!!! help me plz!!?

Of course if you are both connected to the same iCloud account you have the same contacts - what did you expect?. The contacts live on the server and are read from there by the devices; so as you've both managed to sync your contacts up to iCloud they are now inextricably mixed. You can only delete your contacts by deleting individual ones, and doing that will delete them from your phone as well.
You can only unravel this by
1. In the iCloud contacts page at http://icloud.com, select all the contacts, click on the cogwheel icon at bottom left and choose 'Export vCard'.
2. Sign out of System Preferences>iCloud
3. Create a new Apple ID and open a new iCloud account with it for your own use.
4. Import the vCard back into the iCloud contacts page.
5. Go to http://icloud.com and sign in with the original ID. This is now his ID. Work through the contacts individually deleting the ones you don't want him to have. When done sign out and advise him to change his password.
6. Go to the new iCloud account and delete his contacts individually.
Of course if you have also been syncing calendars and using the same email address there are problems with doing this.

UCCX 7.0.1SR5 to 8.0 upgrade while also adding LDAP integration for CUCM - what happens to agents and Historical Reporting data?

Current State:
•    I have a customer running CUCM 6.1 and UCCX 7.01SR5. Currently their CUCM is *NOT* LDAP integrated and using local accounts only. UCCX is AXL integrated to CUCM as usual and is pulling users from CUCM and using CUCM for login validation for CAD.
•    The local user accounts in CUCM currently match the naming format in active directory (John Smith in CUCM is jsmith and John Smith is jsmith in AD)
Goal:
•    Upgrade software versions and migrate to new hardware for UCCX
•    LDAP integrate the CUCM users
Desired Future State and Proposed Upgrade Method
Using the UCCX Pre Upgrade Tool (PUT), backup the current UCCX 7.01 server.
Then during a weekend maintenance window……
•    Upgrade the CUCM cluster from 6.1 to 8.0 in 2 step process
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•    Then build UCCX 8.0 server on new hardware and stop at the initial setup stage
•    Restore the data from the UCCX PUT tool
•    Continue setup per documentation
At this point does UCCX see these agents as the same as they were before?
Is the historical reporting data the same with regards to agent John Smith (local CUCM user) from last week and agent John Smith (LDAP imported CUCM user) from this week ?
I have the feeling that UCCX will see the agents as different almost as if there is a unique identifier that's used in addition to the simple user name.
We can simplify this question along these lines
Starting at the beginning with CUCM 6.1 (local users) and UCCX 7.01. Let's say the customer decided to LDAP integrate the CUCM users and not upgrade any software.
If I follow the same steps with re-associating the users to devices and selecting the ACD/UCCX extension, what happens?
I would guess that UCCX would see all the users it knew about get deleted (making them inactive agents) and the see a whole group of new agents get created.
What would historical reporting show in this case? A set of old agents and a set of new agents treated differently?
Has anyone run into this before?
Is my goal possible while keeping the agent configuration and HR data as it was before?

I was doing some more research looking at the DB schema for UCCX 8.
Looking at the Resource table in UCCX, it looks like there is primary key that represents each user.
My question, is this key replicated from CUCM or created locally when the user is imported into UCCX?
How does UCCX determine if user account jsmith in CUCM, when it’s a local account, is different than user account jsmith in CUCM that is LDAP imported?
Would it be possible (with TAC's help most likely) to edit this field back to the previous values so that AQM and historical reporting would think the user accounts are the same?
Database table name: Resource
The Unified CCX system creates a new record in the Resource table when the Unified CCX system retrieves agent information from the Unified CM.
A Resource record contains information about the resource (agent). One such record exists for each active and inactive resource. When a resource is deleted, the old record is flagged as inactive; when a resource is updated, a new record is created and the old one is flagged as inactive.

New Data in R/3 Enterprise - ABAP Proxies - XI what happen?

Hi,
i have a theoretical question:
if i use R/3 Enterprise on WAS and put new Data in the R/3 System and transport them to XI with ABAP Proxies. What happens in the systems?
How do the R/3 System put new data in the proxy runtime and send them to xi?
I want to unterstand how the transport from new data in a R/3 System with ABAP Proxies comes to the XI Integration Server.

Hi Marcel,
>>>>>How do the R/3 System put new data in the proxy runtime and send them to xi?
all you need to do in r3 is to fill tables of a generated structure
and execute one method of a generated class (send....)
then R3 will connect over HTTP to XI and send the data from your structures
structures and class in R3 is being generated automatically via TCODE SPROXY
Regards,
michal
<a href="/people/michal.krawczyk2/blog/2005/06/28/xipi-faq-frequently-asked-questions"><b>XI / PI FAQ - Frequently Asked Questions</b></a>

What happen if i use controll break statement in between select & endselect

Hi all,
what happen if i use controll break statement in between select & endselect ?
Thanks in Advance
KR

Hi for reference u can go through this code example
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fs_tab like sflight.
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HT5624 What happened to all my library? I don't have an Iphone only an Ipod. But only my recent purchases show up on my computer. How do I get them back?

What happened to my entire 3000+ songs in my library I used to see when I opened iTunes? I only see the most recently purchased. How do I get them back? I don't have an I phone to play they on, only a droid.
Pammie49

Hi Sarah,
It sounds like the songs have either not yet synced over to the iPhone, or something went wrong when attempting to sync to the iPhone. My recommendation is to uncheck the "Sync Music" checkbox.
Once you have done that, recheck the "Sync Music" checkbox, and apply the changes once more. This will instruct iTunes to completely remove all music from your iPhone, and then copy the files once more. If you have a large amount of music, this initial sync may take a while.
If the above does not resolve your issue, see the following articles:
iOS: Syncing with iTunes
http://support.apple.com/kb/HT1386
iOS: How to transfer or sync content to your computer
http://support.apple.com/kb/HT1296
Thanks,
Matt M.

I erased an iphone on find my iphone , so i wanted to know what happened and I erased my without a sim card and now I says I cant go on it until i put in a sim card. Did i ruin the phone please help thanks.

I erased an iphone on find my iphone , so i wanted to know what happened and I erased my without a sim card and now I says I cant go on it until i put in a sim card. Did i ruin the phone please help thanks.

You did not ruin the phone, you will need a sim card to activate the phone and then connect the phone to itunes and do a restore from back up.
http://support.apple.com/kb/HT1414

Help I just installed the latest update on my IPhone4 and now I can't open any of my stored podcasts. When I hit the podcast icon, the screen goes white for a second and the goes back to the opening page with all the icons. What happened?

Help! I just installed the latest update on my IPhone 4 and now I can't access my podcasts. When I hit the podcast I on, the screen goes blank for a second and then opens to the home screen with all my icons. What happened?

Try a reset which is similar to a computer restart and is done by pressing and holding the home button and the sleep/wake or on/off button simultaneously you see the Apple logo and then release.

What happens in jvm

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