Are thread-safe queues

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• OTMQ + JCA - it is thread-safe?

  Hello

  Currently, we are conducting a doubt in our minds regarding using the OTMQ with a JCA component. We build into our architecture a component in order to call by a java bean that is deployed inside a WL server, an OTMQ instance that is running on the same machine. This OTMQ instance is the platform independent (not Tuxedo + OTMQ) OTMQ and on the side of Java, we would use a mixture of JCA and, if necessary, JNI calls to establish a connection between these two components.

  My question here is, because WL will have multiple instances of this bean, are there problems I should be aware with respect, using multiple threads in such a component? In my view, that should we not we have no problem with that, given that OTMQ works similar like Tuxedo/q, but I was wondering if there is something you miss here.

  If you could just help me understand if I am having trouble with this architecture, I would be very grateful.

  Thank you

  brunno Attorre

  Hi Brunno,

  The JCA adapter is thread-safe, and if you find any problems associated with the JCA adapter threads, report it to the Support of Oracle.  About OTMQ, in my opinion, that these libraries are thread-safe, you can create an OTMQ multi-threaded server, but we do not support the use of JNI to call one of our libraries.  Why would you use JNI?  You can simply use the JCA/waiting for Message Queuing adapter.

  Kind regards

  Todd little

  Chief Architect of Oracle Tuxedo

• BBM SDK Thread Safe?

  Anyone know if the messages sent/received are thread-safe, or do we do us our own synchronization to ensure that a new message does not come before the end of the old?

  In this case messages would be delivered in the order they are received.  Each call is on the same thread.

• Is JTextArea append() method thread-safe?

  It was noted in another ad that in JDK 7, the JTextArea append() method is more explicitly described as being thread-safe:
  
  http://download.Java.NET/jdk7/docs/API/javax/swing/JTextArea.html#append
  I do not use JDK7, but here is the code for the method append in JDK6_7 (I guess that he has not changed in JDK7?):
  

  public void append(String str) {
      Document doc = getDocument();
      if (doc != null) {
          try {
              doc.insertString(doc.getLength(), str, null);
          }
          catch (BadLocationException e) {
          }
      }
  }

  As you can see the code simply calls the insertString (...) method of the Document. JDK7 documentation, the insertString (...) method is still marked as being thread-safe:
  
  http://download.Java.NET/jdk7/docs/API/javax/swing/text/PlainDocument.html#insertString
  
  I always confused when you work with Threads. A few questions:
  
  (1) if the append() method eventually calls insertString (...), which is a safe method of thread that does the method append() safe thread?
  
  (2) assuming that the code in the method append has not changed in JDK 7 documentation has been bad for the first 6 versions of the JDK? Or is the documentation for JDK 7 lack instruction thread safe?
  
  (3) I know in the past I've suggested append() is thread-safe. It seems I should change my advice to wrap this method in a SwingUtilities.invokeLater (...). Is this a safe approach in any case to avoid confusion?

  camickr wrote:
  The PlainDocument does not use a lock. Here's the code for the JDK6:

  The lock is #insertString AbstractDocument. The additional filter of PlainDocument #insertString code is thread-safe, because it uses only local variables and GetFilter() reading is true or false/null.

  Even if filtering is not done, is it not theoretically possible that change of threads can occur before the super.insertString (...) is running?

  I guess what I'm asking is that if a single line of code runs before the writeLock() method is called is there way for there to be threading issues?

  Yes, but it's similar to the way in which a synchronized map is thread-safe, you can call containsKey (k) followed by get (k), and these methods are "thread-safe", but if you want to combine you need to do an extra lock. The only thread safe object is immutable.
  One difference here is that a card will return NULL but AbstractDocument launches a BadLocationException. Also if you want to get the lock, the only option is to subclass since writeLock() is protected and final.

• is NamedCache thread-safe?

  Hello
  
  I use coherance NamedCache (say "TradeCache"), to store objects in the cache.
  
  My application is designed so that multiple threads can place data in "TradeCache" at the same time.
  
  What kind of thread safety, we need to take care of?

  Hi user 1696.

  With regard to your questions:

  (a) what kind of locking is used, is that they lock the entire map?
  (b) or basic locking key is made?

  Coherence use essential basic locking.

  (c) if by default all implementations are thread-safe, which is the use of namedcache.lock () api

  NamedCache.lock () is provided so that applications that make use of coherence can have some control over several readers and/or authors using the same object in space of the application. This is not to prevent corruption in the cache store. It must provide a way for applications to control the race as conditions have several operations on the same object at the same time. So that the application can control which of the puts should occur for example.

  Can you please me to any document (short & concise) cohernace good.

  You can find pointers to official documentation and white papers, among others to the OTN on Oracle coherence page following

  http://www.Oracle.com/technology/products/coherence/coherence_suite.html

  and there is also a wealth of information on the site of the Oracle coherence Knowledge Base at:

  http://coherence.Oracle.com

  In regards to your 2nd question about 2 java clients using the same NamedCache and do put and remove operations, you can provide more details on your example? Java clients 2 performing put or remove on the same object or different objects?

  Patrick

  Published by: P Fry on April 30, 2010 12:09

• Thread Safe variables - several symbol at link definitions

  I'm going through the tutorial "Multithreading in LabWindows/CVI.

  The following line is in the tutorial about the variables in Thread-Safe:

  "If you need to access the variable in thread-safe from more than one file source, use the macro DeclareThreadSafeScalarVar or DeclareThreadSafeArrayVar in an include (.h) file for create statements for the accessor functions."

  OK works with a source file, but when I include the header file in a second file from the source, I have "Several definitions for symbol" errors when link for all functions of accessor in the two source files.

  It's probably something simple, but after a few hours I'm at a loss. Any ideas are appreciated.

  Scott T

  You should have DefineThreadSafeXXX in exactly a source file and a DeclareThreadSafeXXX in any number of source files (or in a file header included in the source files). The following works for me in 2012 of the CVI:

  / * temp.h * /.

  #include

  DeclareThreadSafeScalarVar (double, Num);

  void test (void);

  * Temp.c * /.

  #include "temp.h".

  DefineThreadSafeScalarVar (double, Num,-1);

  void main (void) {}

  InitializeNum();

  test();

  }

  / * temp2.c * /.

  #include "temp.h".

  void test (void) {}

  SetNum (1.0);

  }

• Does container managed entity manager is thread-safe in stateless session bean?

  Hello

  I have read JEE6 doc and confused with

  Manager managed entity containing does (injected by PersistenceContext annotation) is thread-safe in bean of stateless session in env mutiple-thread?

  See code below, if there are 2 requests to stateless session bean in 2 concurrent threads, is it using the same Instance of the managing body or not?

  @Stateless (name = "HRFacade", mappedName = "HR_FACES_EJB_JPA-HRFacade-HRFacade")

  / public class HRFacadeBean implements HRFacade, HRFacadeLocal {}

  @Resource

  SessionContext sessionContext;

  @PersistenceContext (unitName = "HRFacade")

  Private EntityManager em;

  public places (places sites) persistLocations {}
  EM. Persist (rentals);
  return places;
  }

  public places (places sites) mergeLocations {}
  Return em.merge (rentals);
  }

  {} public void removeLocations (places sites)
  location = em.find (Locations.class, locations.getLocationId ());
  EM. Remove (rentals);
  }

  / * < code > o selection of the places where < code > * /.
  @TransactionAttribute (TransactionAttributeType.NOT_SUPPORTED)
  public list < location > getLocationsFindAll() {}
  Return em.createNamedQuery ("Locations.findAll", Locations.class) .getResultList ();
  }

  }

  Yes its safe. Stateless beans would be useless if it wasn't the case. That's the bit of "controlled container" description, as long as you leave the container do its job, you don't have to worry about such details.

• SimpleParser consistency class is not thread-safe?

  Coherense has the utility class to XML very convinent which we use it a lot in our coherence-related applications.
  
  But meet us some lock mysterious question (dead end, maybe?) and have identified that it would be that the com.tangosol.run.xml.SimpleParser class is not thread-safe.
  
  We use tomcat 6 and Spring 2.0.6.
  
  Application Web has 2 bean that implements the InitializingBean interface.
  
  Bean A afterPropertiesSet() method will use com.tangosol.run.xml.XmlHelper.loadXml method to parse a XML file.
  Method of Bean B afterPropertiesSet() will acts as a tcp expand clients and retrieve data from a cluster of coherence. Which, I think, consistency will also use XML class useful during parsing of the configuration files.
  
  We meet randomly blocking of tomcat (which never end starting webapp deployment alternation) as 1 on 2 or 3 tests.
  
  Use of jconsole and tomcat connection we can see that the main thread stuck in the class SimpleParser. Here's the thread dump.
  
  Name: main
  State: EXECUTABLE
  Blocked in total: 156 Total expected: 0
  
  *************************************************************************************************
  
  Stack trace:
  com.tangosol.run.xml.SimpleParser.instantiateDocument(SimpleParser.java:150)
  com.tangosol.run.xml.SimpleParser.parseXml(SimpleParser.java:115)
  -locking com.tangosol.run.xml.SimpleParser@f10c77
  com.tangosol.run.xml.SimpleParser.parseXml(SimpleParser.java:71)
  com.tangosol.run.xml.SimpleParser.parseXml(SimpleParser.java:84)
  com.tangosol.run.xml.XmlHelper.loadXml(XmlHelper.java:109)
  org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1201)
  org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1171)
  org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:425)
  org.springframework.beans.factory.support.AbstractBeanFactory$ 1.getObject(AbstractBeanFactory.java:251)
  org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:156)
  -locking java.util.concurrent.ConcurrentHashMap@dee55c
  org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:248)
  org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:160)
  org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:287)
  org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:352)
  -locking java.lang.Object@d21555
  org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:244)
  org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:187)
  org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:49)
  org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3830)
  org.apache.catalina.core.StandardContext.start(StandardContext.java:4337)
  -locking org.apache.catalina.core.StandardContext@1c64ed8
  org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791)
  -locking java.util.HashMap@76a6d9
  org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771)
  org.apache.catalina.core.StandardHost.addChild(StandardHost.java:525)
  org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:825)
  org.apache.catalina.startup.HostConfig.deployWARs(HostConfig.java:714)
  org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:490)
  org.apache.catalina.startup.HostConfig.start(HostConfig.java:1138)
  org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
  org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
  org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
  -locking org.apache.catalina.core.StandardHost@1c42c4b
  org.apache.catalina.core.StandardHost.start(StandardHost.java:719)
  -locking org.apache.catalina.core.StandardHost@1c42c4b
  org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
  -locking org.apache.catalina.core.StandardEngine@37fd24
  org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
  org.apache.catalina.core.StandardService.start(StandardService.java:516)
  -locking org.apache.catalina.core.StandardEngine@37fd24
  org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
  -locked [Lorg.apache.catalina.Service;@1cc55fb
  org.apache.catalina.startup.Catalina.start(Catalina.java:566)
  sun.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)
  sun.reflect.NativeMethodAccessorImpl.invoke (unknown Source)
  sun.reflect.DelegatingMethodAccessorImpl.invoke (unknown Source)
  java.lang.reflect.Method.invoke (unknown Source)
  org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288)
  org.apache.catalina.startup.Bootstrap.main (Bootstrap.java:413)
  
  *************************************************************************************************
  
  After we have add the tag is based on applying bean B wait on A bean to complete initialization, we encounter is no longer blocked when starting tomcat.
  
  We suspect that maybe SimpleParser class is not thread-safe and will cause potential deadlock issue.
  
  Published by: user639604 on June 22, 2009 10:36

  It seems that the 'hand' thread comes to the point that he is responsible for the class of SimpleDocument around the same time as the thread "Timer-0"comes to the point where he is in charge of the class ExternalizableHelper. According to what son get on-demand, if the loading of the class ExternalizableHelper happens point of needing to SimpleDocument after the main thread starts to load SimpleDocument, then a deadlock (inside the JVM loading infrastructure class) happen.

  While you are correct that it is our fault (we shouldn't have used a subset of the ExternalizableHelper static initializer), there is probably a simple solution; Just do the following in an initializer static for your first loads or the classes related to the coherence, for example ClusterConfigurator and OPCacheManager:

  static
    {
    // this should force the ExternalizableHelper class to be loaded
    ExternalizableHelper.makeTrint(0L);
    }
  

  Peace,

  Cameron Purdy | The Oracle coherence

• Why am I always updates XP on 09/04/14? Are they safe install?

  Why am I always updates XP on 09/04/14? Are they safe install?

  Original title: new update of XP

  Hello

  The automatic update of Windows XP does not more roll of new updates, but in the case where you have not installed previously available update, then it will be available and you can install it at any given time. There is no deadline for availability already rolled on updates for Windows XP.

  It's all of the update by Microsoft for Windows XP:

  http://TechNet.Microsoft.com/en-us/security/bulletin/MS14-Apr

  Service Pack 3 is the latest update available for Windows XP Service Pack.

  For more information, please visit:

  http://support.Microsoft.com/kb/322389/en-us

  See also:

  http://Windows.Microsoft.com/en-CA/Windows/end-support-help

  Hope the helps of information provided.

• tables dynamic thread-safe

  Hi all

  trying to convert my application single-threaded for multithreading, that I met a new obstacle:

  I would like to have a global data structure. This structure must be dynamically allocated and reallocated as the number of threads (and thus the size of the structure) depends on the program execute / user.

  The main thread as long as secondary threads should be able to access this structure, so I need to use a variable in thread safe, somehow. All the samples I've traveled so far, either use a single variable using the DefineThreadSafeScalarVar macro, or an array of size fixed by using the DefineThreadSafeArrayVar macro.

  I haven't found an example of this type of a dynamic array, unfortunately... Some kind soul would be willing to teach me how to proceed?

  Thank you

  Wolfgang

  In your case, you must use a TSV scalar that contains the pointer is allocated/re-allocated. See the following example of a TSV that mimics a dynamic array of integers. In some cases, a better solution would be to have a TSV scalar that contains a list, say, box tools ListType.

  #include

  DefineThreadSafeVar (int *, DynMem);

  void main (void)
  {
  int * pDynMem, i.;
     
  Initialize the TSV
  InitializeDynMem();
     
  Define HSV 'table' to hold 10 integers
  SetDynMem (malloc (10 * sizeof (int)));
     
  Set and get the 'elements' of TSV
  pDynMem = GetPointerToDynMem();
  for (i = 0; i< 10;="">
  {
  (* pDynMem) [i] = i;
  printf ("DynMem [%d] = %d\n", (* pDynMem) [i], i);
  }
  ReleasePointerToDynMem();
     
  Resize the TSV "array".
  pDynMem = GetPointerToDynMem();
  * pDynMem = realloc (* pDynMem, 20 * sizeof;)
  for (i = 10; I)< 20;="">
  (* pDynMem) [i] = i;
  for (i = 0; i< 20;="">
  printf ("DynMem [%d] = %d\n", (* pDynMem) [i], i);
  ReleasePointerToDynMem();
     
  Free TSV "array".
  pDynMem = GetPointerToDynMem();
  Free(*pDynMem);
  ReleasePointerToDynMem();
     
  Cancel initialization of TSV
  UninitializeDynMem();
  }

• This is the software under the C:\Program Files\Bench. Are they safe?

  Original title:

  bench software

  There are software under C:\Program Files\Bench. Are they safe, or should I uninstall them. I suspect that they are causing problems for my computer.

  No idea who wrote it.

  Search for malicious software.

  See you soon.

• Are gadgets safe?

  There are a few updates to the operating system my gadget CPU/RAM began to appear degraded, although it always gives me valuable information.
  It is my understanding that, due to a security breach, MS has stopped gadgets.
  The Fix It solution is necessary, or did the update that has paralyzed gadgets eliminate the vulnerability?
  That is to say. It is safe for me to continue to use my gadget CPU/RAM in its degraded state? (MS all updates installed, but Fix It solution does not applied)

  No, the gadgets are not safe.  They can be exploited by hackers.

  There is another discussion in these links, but they describe only disabling gadgets, i.e. There is no solution to your problem in another way to turn them off.  If you disable Gadgets then the vulnerability is closed.

  Vulnerabilities in Gadgets could allow Remote Code execution

  How to protect Windows Vista and Windows 7 to Windows Sidebar Gadgets operating systems [note that references to Gadgets of the component must be read as applying to the Gadgets in general - they are the same thing]

  Microsoft Security Advisory: Vulnerabilities in Gadgets could allow remote code execution

  You can use the links to run the Fixit or modify the registry manually.  You can also disable the Gadgets to

  Control Panel, [view by - small icons, if necessary], programs & features, turn Windows features on or off - clear the check box next to the Windows gadget platform , and then click OK.

• Why my emails are threaded even though my tri is set to not threaded?

  My view > sort by > is Unthreaded, yet when I mark an email as "Read" it marks randomly as other messages to read that I have not really read yet. No, I don't have the addons for the filtering of conversations. Yes, I've read this Q & A https://support.mozilla.org/en-US/questions/989629?esab=a & as = aaq response which says that even if the right click list drop-down Mark > as read option shows the 'R' stressed to use 'R' to mark a message as read, 'R' will mark the entire thread as read. My question is, how can he score 'a thread"Red when a thread does not exist since sorting by vision is defined as non-threaded? I am grateful for the suggestion to use'm ' to switch between read and unread on a single message, status because it does not have to mark a single message as read! However, in every other sense messages are always treated as they pass even if I put the view > sort by > as Unthreaded. Is there ANY other way to disable thread outside the view > sort by options? Or at least change the way Thunderbird put together topics of conversation?

  See here http://kb.mozillazine.org/Stop_threading_by_subject
  and https://wiki.mozilla.org/MailNews:Message_Threading

  I think that should cover the basics as well as some details.

  When an email is created a reference is given by its creator, that that Thunderbird, Gmail or Outlook. This reference is supposed to be unique in the world, or nearby value. Most of the things nowadays use GUIDS but mail really precedes this concept, so old messages requires only a reference. Gmail has put references that look like this in my mail

  Message-ID: < [email protected] >
  

  It is this reference which is the base of the thread. Who and when I click to answer or forward, another header is added

  References: <[email protected]> <[email protected]>
  

  In this example, there are two previous E-mail listed in the references.

  When Thunderbird Threads of this mail, it takes three values and looking in the mailbox for other messages with these three entries, because they a related danger one is the message that was sent and the following two are responded and returned again to the answers.

  Now, we get to the really unfortunate part of the process. Most web developers know squat about electronic mail; The same can be said of more general developers, but they continue to get the specifications for programs send a mail and they do horribly wrong. Often they copy a bit badly written JavaScript and paste it into a web page and the e-mail box. Worse still is the weekend hacker who develops a nice web page for the butcher, hairdresser (fill in business here) and copies all sorts of poorly written but functional JavaScript into the pot.

  So exactly why these emails would be strung, I don't know, because the subject is a very minor factor. You can enlighten us by looking at references and Message-id headers.

  You have installed add-ons?

• everytime I open a new tab, there are avg safe search

  Hey guys, so, recently, I opened firefox, open a new tab to display all my nail of the thumb, and instead, I just see AVG safe search. I hate it. I've tried everything. I tried to restart firefox, I deleted and uninstalled everything related to distance of AVG and I have no extensions of AVG, I deleted the AVG toolbar but safe search is still there! Help, please! I really want these vignettes of return! By the way, I have windows 8.1

  Do a clean reinstall and delete the program folder before Firefox to (re) install a new copy of the current version of Firefox.

  Download a new copy of Firefox and save the file to the desktop.

  • Firefox 26: http://www.mozilla.org/en-US/firefox/all.html

  If possible to uninstall your current version of Firefox to clean the Windows registry and settings in the security software.

  • Do NOT remove the data personal when you uninstall your current version of Firefox, because all profile files will be deleted and you lose personal data such as bookmarks and passwords from other versions of Firefox profiles.

  Delete the program folder Firefox before installing newly downloaded copy of the Firefox installer.

  • (32-bit Windows) "C:\Program Files\Mozilla Firefox\"
  • (Windows 64 bit) "C:\Program Files (x 86) \Mozilla.
  • It is important to remove the Firefox program folder to delete all the files and make sure that there is no problem with the files that were the remains after uninstallation.
  • http://KB.mozillazine.org/Uninstalling_Firefox

  Your bookmarks and other personal data are stored in the Firefox profile folder and will not be affected by a uninstall and (re) install, but make sure that 'delete personal data' is NOT selected when you uninstall Firefox.

  If you keep problems also create a new profile.

  • http://KB.mozillazine.org/Profile_folder_-_Firefox
  • http://KB.mozillazine.org/Profile_backup
  • http://KB.mozillazine.org/Standard_diagnostic_-_Firefox#Clean_reinstall

• Complete a teststand thread safe

  Hello

  I created a vi using the audio wizard and vibrations. He simpply plays a tone of 1 kHz. I start it to use a new thread execution in TestStand (generate the audio wire)

  I then proceed to route the audio from my USE speaker R - the operator must then select the pass/fail if hear sound out of the speaker.

  Then, I continue to send the sound to the speaker L and provide a pass/fail another popup.

  I wonder how I can kill the audio thread 'generate' without including a timeout routine in my vi?

  Not sure if this is possible or safe?

  Thanks & best regards,

  Shane.

  Hey Don1,.

  It seems that this could be an easy fix if I understand your problem. The idea is to have the operator, click go, and then a tone is played on the right side, they confirm / deny hearing it and then it moves on the left side and confirm or deny. The best way to take care of this would be to use only one step for each audio side, for a total if you want, but the idea is to have the LabVIEW to hold the popup of user until the user interacts with it. This could be accomplished with separate vi have by a dialog box pop-up in a while loop when the right audio is running, once the user confirms audio, it stops the loop and returns the result to TestStand. They can then move to the left audio in the same way. If you prefer this in one step, you could use consecutive while loops to hold the user up to the interaction operator dialog box and then move on to the next audio side and then pass the results back as needed.

  Thanks again,

  Nick