Search Results

Search found 1977 results on 80 pages for 'concurrent modification'.

Page 21/80 | < Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >

  • How to use third party themes in swing application?

    - by swift
    I want to use some third party themes (like synthetica http://www.javasoft.de/synthetica/themes/) in my swing appliaction. i am using eclipse ide, got the jar file of theme and did the following modification(according to the readme file from the theme) in my code try { UIManager.setLookAndFeel(new SyntheticaBlackMoonLookAndFeel()); } catch (Exception e) { e.printStackTrace(); } but after this modification its showing the following error The type de.javasoft.plaf.synthetica.SyntheticaLookAndFeel cannot be resolved. It is indirectly referenced from required .class files what does this mean? i tried searching on net but cant really find any useful answers Contents of Readme file: System Requirements =================== Java SE 5 (JRE 1.5.0) or above Synthetica V2.2.0 or above Integration =========== 1. Ensure that your classpath contains all Synthetica libraries (including Synthetica's core library 'synthetica.jar'). 2. Enable the Synthetica Look and Feel at startup time in your application: import de.javasoft.plaf.synthetica.SyntheticaBlackMoonLookAndFeel; try { UIManager.setLookAndFeel(new SyntheticaBlackMoonLookAndFeel()); } catch (Exception e) { e.printStackTrace(); }

    Read the article

  • Do MyISAM holes get filled in automatically?

    - by NNN
    When you run a delete on a MyISAM table, it leaves a hole in the table until the table is optimized. This affects concurrent inserts. On the default setting, concurrent_inserts only work for tables without holes. However, in the documentation for MyISAM, under the concurrent_insert section it says: Enables concurrent inserts for all MyISAM tables, even those that have holes. For a table with a hole, new rows are inserted at the end of the table if it is in use by another thread. Otherwise, MySQL acquires a normal write lock and inserts the row into the hole. http://dev.mysql.com/doc/refman/5.0/en/server-system-variables.html#sysvar_concurrent_insert Does that mean MyISAM automatically fills in holes whenever a new row is insert into the table? Previously I thought the holes would not be fixed until you OPTIMIZE a table.

    Read the article

  • spring web application context is not loaded from jar file in WEB-INF/lib when running tomcat in eclipse

    - by Remy J
    I am experimenting with spring, maven, and eclipse but stumbling on a weird issue. I am running Eclipse Helios SR1 with the STS (Spring tools suite) plugin which includes the Maven plugin also. What i want to achieve is a spring mvc webapp which uses an application context loaded from a local application context xml file, but also from other application contexts in jar files dependencies included in WEB-INF/lib. What i'd ultimately like to do is have my persistence layer separated in its own jar file but containing its own spring context files with persistence specific configuration (e.g a jpa entityManagerFactory for example). So to experiment with loading resources from jar dependencies, i created a simple maven project from eclipse, which defines an applicationContext.xml file in src/main/resources Inside, i define a bean <bean id="mybean" class="org.test.MyClass" /> and create the class in the org.test package I run mvn-install from eclipse, which generates me a jar file containing my class and the applicationContext.xml file: testproj.jar |_META-INF |_org |_test |_MyClass.class |_applicationContext.xml I then create a spring mvc project from the Spring template projects provided by STS. I have configured an instance of Tomcat 7.0.8 , and also an instance of springSource tc Server within eclipse. Deploying the newly created project on both servers works without problem. I then add my previous project as a maven dependency of the mvc project. the jar file is correctly added in the Maven Dependencies of the project. In the web.xml that is generated, i now want to load the applicationContext.xml from the jar file as well as the existing one generated for the project. My web.xml now looks like this: org.springframework.web.context.ContextLoaderListener <!-- Processes application requests --> <servlet> <servlet-name>appServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value> classpath*:applicationContext.xml, /WEB-INF/spring/appServlet/servlet-context.xml </param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>appServlet</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> Also, in my servlet-context.xml, i have the following: <context:component-scan base-package="org.test" /> <context:component-scan base-package="org.remy.mvc" /> to load classes from the jar spring context (org.test) and to load controllers from the mvc app context. I also change one of my controllers in org.remy.mvc to autowire MyClass to verify that loading the context has worked as intended. public class MyController { @Autowired private MyClass myClass; public void setMyClass(MyClass myClass) { this.myClass = myClass; } public MyClass getMyClass() { return myClass; } [...] } Now this is the weird bit: If i deploy the spring mvc web on my tomcat instance inside eclipse (run on server...) I get the following error : org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping#0': Initialization of bean failed; nested exception is java.lang.NoClassDefFoundError: org/test/MyClass at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:527) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:580) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425) at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:442) at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:458) at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:339) at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:306) at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:127) at javax.servlet.GenericServlet.init(GenericServlet.java:160) at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1133) at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1087) at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:996) at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4834) at org.apache.catalina.core.StandardContext$3.call(StandardContext.java:5155) at org.apache.catalina.core.StandardContext$3.call(StandardContext.java:5150) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:885) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907) at java.lang.Thread.run(Thread.java:619) Caused by: java.lang.NoClassDefFoundError: org/test/MyClass at java.lang.Class.getDeclaredMethods0(Native Method) at java.lang.Class.privateGetDeclaredMethods(Class.java:2427) at java.lang.Class.getDeclaredMethods(Class.java:1791) at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:446) at org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping.determineUrlsForHandlerMethods(DefaultAnnotationHandlerMapping.java:172) at org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping.determineUrlsForHandler(DefaultAnnotationHandlerMapping.java:118) at org.springframework.web.servlet.handler.AbstractDetectingUrlHandlerMapping.detectHandlers(AbstractDetectingUrlHandlerMapping.java:79) at org.springframework.web.servlet.handler.AbstractDetectingUrlHandlerMapping.initApplicationContext(AbstractDetectingUrlHandlerMapping.java:58) at org.springframework.context.support.ApplicationObjectSupport.initApplicationContext(ApplicationObjectSupport.java:119) at org.springframework.web.context.support.WebApplicationObjectSupport.initApplicationContext(WebApplicationObjectSupport.java:72) at org.springframework.context.support.ApplicationObjectSupport.setApplicationContext(ApplicationObjectSupport.java:73) at org.springframework.context.support.ApplicationContextAwareProcessor.invokeAwareInterfaces(ApplicationContextAwareProcessor.java:106) at org.springframework.context.support.ApplicationContextAwareProcessor.postProcessBeforeInitialization(ApplicationContextAwareProcessor.java:85) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsBeforeInitialization(AbstractAutowireCapableBeanFactory.java:394) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1413) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519) ... 25 more 20-Feb-2011 10:54:53 org.apache.catalina.core.ApplicationContext log SEVERE: StandardWrapper.Throwable org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping#0': Initialization of bean failed; nested exception is java.lang.NoClassDefFoundError: org/test/MyClass If i build the war file (using maven "install" goal), and then deploy that war file in the webapps directory of a standalone tomcat server (7.0.8 as well) it WORKS :-( What am i missing ? Thanks for the help.

    Read the article

  • How/is data shared between fastCGI processes?

    - by Josh the Goods
    I've written a simple perl script that I'm running via fastCGI on Apache. The application loads a set of XML data files which are used to lookup values based upon the the query parameters of an incoming request. As I understand it, if I want to increase the amount of concurrent requests my application can handle I need to allow fastCGI to spawn multiple processes. Will each of these processes have to hold duplicate copies of the XML data in memory? Is there a way to set things up so that I can have one copy of the XML data loaded in memory while increasing the capacity to handle concurrent requests?

    Read the article

  • java.io.FileNotFoundException for valid URL

    - by Alexei
    Hello. I use library rome.dev.java.net to fetch RSS. Code is URL feedUrl = new URL("http://planet.rubyonrails.ru/xml/rss"); SyndFeedInput input = new SyndFeedInput(); SyndFeed feed = input.build(new XmlReader(feedUrl)); You can check that http://planet.rubyonrails.ru/xml/rss is valid URL and the page is shown in browser. But I get exception from my application java.io.FileNotFoundException: http://planet.rubyonrails.ru/xml/rss at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1311) at com.sun.syndication.io.XmlReader.<init>(XmlReader.java:237) at com.sun.syndication.io.XmlReader.<init>(XmlReader.java:213) at rssdaemonapp.ValidatorThread.run(ValidatorThread.java:32) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:619) I don't use any proxy. I get this exception on my PC and on the production server and only for this URL, other URLs are working.

    Read the article

  • Recommendations for an in memory database vs thread safe data structures

    - by yx
    TLDR: What are the pros/cons of using an in-memory database vs locks and concurrent data structures? I am currently working on an application that has many (possibly remote) displays that collect live data from multiple data sources and renders them on screen in real time. One of the other developers have suggested the use of an in memory database instead of doing it the standard way our other systems behaves, which is to use concurrent hashmaps, queues, arrays, and other objects to store the graphical objects and handling them safely with locks if necessary. His argument is that the DB will lessen the need to worry about concurrency since it will handle read/write locks automatically, and also the DB will offer an easier way to structure the data into as many tables as we need instead of having create hashmaps of hashmaps of lists, etc and keeping track of it all. I do not have much DB experience myself so I am asking fellow SO users what experiences they have had and what are the pros & cons of inserting the DB into the system?

    Read the article

  • How can I find file system concurrency issues ?

    - by krosenvold
    I have an application running on Linux, and I find myself wanting windows (!). The problem is that every 1000 times or so I run into concurrency problems that are consistent with concurrent reading/writing of files. I am fairly sure that this behavior would be prohibited by file locking under Windows, but I don't have any sufficiently fast windows box to check. There is simply too much file access (too much data) to expect strace to work reliably - the sheer volume of output is likely to change the problem too. It also happens on different files every time. Ideally I would like to change/reconfigure the linux file system to be more restrictive (as in fail-fast) wrt concurrent access. Are there any tools/settings I can use to achieve this ?

    Read the article

  • What Data structure for Reputation Rules in C# (like stackoverflow)

    - by optician
    I am currently building a system which will have entities that will have scores like reputation etc.. I will have a service that will check for certain rules having been triggered, and will perform certain logic if they are triggered. Previously I have used say an Enum for doing this when I have only had to store an id and a description. public enum ShoppingCratCalculation { PartialCalculation = 1, CompleteCalculation =2 } But in this situation I want to carry more information, such as the modification to reputation, all in one place. I'm essentially asking what data structure would be best suited to storing this information, for each rule in the system. 1. Description = string ("User forgot to write a review") 2. DB id = int (23) 3. Rep score modification = int (-5) Maybe a little class (Rule) with these as properties , and then just a list? Does anyone have any best practice suggestions for this kind of struct?

    Read the article

  • combination of open source licenses

    - by Nicola Montecchio
    Hi I'm about to release some software as open source. It uses Lucene (Apache license) and jopt simple (MIT license). Are there any constraints on the license that I am going to apply to my own software? In particular, it is an adaptation of Lucene for performing content-based search on audio (so, many classes are inherited and in one case copied with a little modification). It only uses jopt simple for handling command line arguments (i.e. no modification at all, just "import" and "new OptionParser..."). Thanks for your help Nicola Montecchio

    Read the article

  • Disabling FileSystemWatcher for specific updates?

    - by chaiguy
    Does anyone have any ideas how I can reliably disable a FileSystemWatcher object when my application makes changes to the files in the directory, so that I am only watching for external changes to the directory? I've tried setting EnableRaisingEvents to false immediately before performing a write and setting it back to true immediately after, but it seems this method is not reliable, and occasionally I still get the event firing. The only other thing I can think of is to wait a small amount of time after performing the write to let the OS finish up the modification of the directory before re-enabling the FSW, but that seems hackish and I don't like it. To add to the problem, the directory consists of potentially many files, the identities of which are beyond my knowledge and control, so I can't just wait for the event to fire for a specific file and then ignore it. There could be any number of FSW events firing after a single modification (because of the potentially many files getting updated).

    Read the article

  • What is the chance a CouchDB document update handler will get a revision conflict?

    - by jhs
    How likely is a revision conflict when using an update handler? Should I concern myself with conflict-handling code when writing a robust update function? As described in Document Update Handlers, CouchDB 0.10 and later allows on-demand server-side document modification. Update handlers can process non-JSON formats; but the other major features are these: An HTTP front-end to arbitrarily complex document modification code Similar code needn't be written for all possible clients—a DRY architecture Execution is faster and less likely to hit a revision conflict I am unclear about the third point. Executing locally, the update handler will run much faster and with lower latency. But in situations with high contention, that does not guarantee a successful update. Or does the update handler guarantee a successful update?

    Read the article

  • Actors in Scala.net

    - by weijiajun
    I have recently completed some study of erlang, and was intrigued by scala for its feature set and the ease of interpolating with java (and possibly .net) applications. I am finally studying actors and was wondering if there is an actor mechanism that currently works in .net. I have looked at the libararies that come down with sbaz and have found that there is a scala.Concurrent but no scala.actors.Actor. I tried to use the scala.Concurrent.Channel but was unable to use the ! to send messages. I was just wondering if this is something that is currently available and if so how do you go about setting it up.

    Read the article

  • what is the pattern for modifying a collection in C#

    - by macias
    What is the pattern (best practice) for such problem -- modifying elements (values) in collection? Conditions: size of the collection is not changed (no element is deleted or added) modification is in-place In C++ it was easy and nice, I just iterated trough a collection and changed the elements. But in C# iterating (using enumerator) is read-only operation (speaking in terms of C++, only const_iterator is available). So, how to do this in C#? Example: having sequence of "1,2,3,4" modification is changing it to "1, 2, 8, 9" but not "1, 2, 3" or "1, 2, 3, 4, 5".

    Read the article

  • Known problems with filemtime() on Windows - files getting touched arbitrarily?

    - by Pekka
    Is there a known issue leading to file modification times of cache files on Windows XP SP 3 getting arbitrarily updated, but without any actual change? Is there some service on a standard Windows XP - Backup, Sync, Versioning, Virus scanner - known to touch files? They all have a .txt extension. If there isn't, forget it. Then I'm getting something wrong in my cache routines, and I'll debug my way through. Background: I'm building a simple caching wrapper around a slow web site on a Windows server. I am comparing the filemtime() time stamp to some columns in the data base to determine whether a cached file is stale. I'm having problems using this method because the modification time of the cache files seems to get updated in between operations without me doing anything. THis results in stale files being displayed. I'm the only user on the machine. The operating system is Windows XP, the webserver a XAMPP Apache 2 with PHP 5.2

    Read the article

  • Android UnknownHost in asyncTask - loading web page

    - by Sneha
    I followed this tutorial for AsyncTask and getting the following error log: 03-23 11:44:42.936: WARN/System.err(315): java.net.UnknownHostException: www.google.co.in 03-23 11:44:42.936: WARN/System.err(315): at java.net.InetAddress.lookupHostByName(InetAddress.java:513) 03-23 11:44:42.936: WARN/System.err(315): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:278) 03-23 11:44:42.936: WARN/System.err(315): at java.net.InetAddress.getAllByName(InetAddress.java:242) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:136) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:348) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555) 03-23 11:44:42.936: WARN/System.err(315): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487) 03-23 11:44:42.944: WARN/System.err(315): at org.apache.http.impl.client.AbstractHttpC lient.execute(AbstractHttpClient.java:465) 03-23 11:44:42.944: WARN/System.err(315): at com.test.async.AsyncTaskExampleActivity$DownloadWebPageTask.doInBackground (AsyncTaskExampleActivity.java:36) 03-23 11:44:42.944: WARN/System.err(315): at com.test.async.AsyncTaskExampleActivity$DownloadWebPageTask.doInBackground (AsyncTaskExampleActivity.java:1) 03-23 11:44:42.944: WARN/System.err(315): at android.os.AsyncTask$2.call(AsyncTask.java:185) 03-23 11:44:42.944: WARN/System.err(315): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305) 03-23 11:44:42.944: WARN/System.err(315): at java.util.concurrent.FutureTask.run (FutureTask.java:137) 03-23 11:44:42.944: WARN/System.err(315): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068) 03-23 11:44:42.944: WARN/System.err(315): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561) 03-23 11:44:42.944: WARN/System.err(315): at java.lang.Thread.run(Thread.java:1096) How do i fix it?? My Code: public class AsyncTaskExampleActivity extends Activity { private TextView textView; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); textView = (TextView) findViewById(R.id.TextView01); } private class DownloadWebPageTask extends AsyncTask<String, Void, String> { @Override protected String doInBackground(String... urls) { String response = ""; Log.i("", "in doInBackgroundddddddddd.........."); Log.i("", "in readWebpageeeeeeeeeeeee"); /* * try { InetAddress i = * InetAddress.getByName("http://google.co.in"); } catch * (UnknownHostException e1) { e1.printStackTrace(); } */ for (String url : urls) { Log.i("", "in for looooooop doInBackgroundddddddddd.........."); DefaultHttpClient client = new DefaultHttpClient(); HttpGet httpGet = new HttpGet(url); try { Log .i("", "afetr for looooooop try doInBackgroundddddddddd.........."); HttpResponse execute = client.execute(httpGet); Log .i("", "afetr for looooooop try client ..execute doInBackgroundddddddddd.........."); InputStream content = execute.getEntity().getContent(); BufferedReader buffer = new BufferedReader( new InputStreamReader(content)); String s = ""; while ((s = buffer.readLine()) != null) { response += s; Log .i("", "afetr while looooooop try client ..execute doInBackgroundddddddddd.........."); } } catch (Exception e) { e.printStackTrace(); } } Log .i("", "afetr lasttttttttttttt b4 response doInBackgroundddddddddd.........."); return response; } @Override protected void onPostExecute(String result) { Log.i("", "in onPostExecuteeee.........."); textView.setText(result); } } public void readWebpage(View view) { /* * System.setProperty("http.proxyHost", "10.132.116.10"); * System.setProperty("http.proxyPort", "3128"); */ DownloadWebPageTask task = new DownloadWebPageTask(); task.execute(new String[] { "http://google.co.in" }); Log.i("", "in readWebpageeeeeeeeeeeee after execute.........."); } } main.xml: <Button android:id="@+id/readWebpage" android:layout_width="match_parent" android:layout_height="wrap_content" android:onClick="readWebpage" android:text="Load Webpage"> </Button> <TextView android:id="@+id/TextView01" android:layout_width="match_parent" android:layout_height="match_parent" android:text="Example Text"> </TextView> Manifest: <?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.test.async" android:versionCode="1" android:versionName="1.0"> <uses-sdk android:minSdkVersion="8" /> <uses-permission android:name="android.permission.INTERNET"></uses-permission> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".AsyncTaskExampleActivity" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> Thanks Sneha

    Read the article

  • Best wrapper for simultaneous API requests?

    - by bluebit
    I am looking for the easiest, simplest way to access web APIs that return either JSON or XML, with concurrent requests. For example, I would like to call the twitter search API and return 5 pages of results at the same time (5 requests). The results should ideally be integrated and returned in one array of hashes. I have about 15 APIs that I will be using, and already have code to access them individually (using simple a NET HTTP request) and parse them, but I need to make these requests concurrent in the easiest way possible. Additionally, any error handling for JSON/XML parsing is a bonus.

    Read the article

  • MS Access vs SQL Server and others ? Is it worth taking a db server when less than 2 Gb and only 20

    - by asksuperuser
    After my experiment with MSAccess vs MySQL which shows MS Access hugely overperforming Mysql odbc insert by a factor 1000% before I would do the same experiment with SQL Server I searched for some other's people and found this one: http://blog.nkadesign.com/2009/access-vs-sql-server-some-stats-part-1/ which says "As a side note, in this particular test, Access offers much better raw performance than SQL Server. In more complex scenarios it’s very likely that Access’ performance would degrade more than SQL Server, but it’s nice to see that Access isn’t a sloth." So is worth bother with some db server when data is less than 2 Gb and users are about 20 (knowing that MS Access theorically supports up to 255 concurrent users though practically it's around a dozen concurrent users only). Are there any real world studies that really compare MS Access with other db in these specific use case ? Because professionaly speaking I keep hearing people systematically recommend DB server from people who have never used Access just because they think DB Server can only perform better in every case which I used to think myself I confess.

    Read the article

  • Confirmation before closing

    - by saeed
    Hi I am using c# .net windows form application. I have a combo box and a text box and a close window button. Now If I make any change in the combo box or textbox and click on the close window button, it should prompt the user to save the modifications.. If no modification are made ( The user will just run the application, doesnt make any modification) then it should not prompt the user. It should close directly.. How can I do this?

    Read the article

  • Handling file upload in a non-blocking manner

    - by Kaliyug Antagonist
    The background thread is here Just to make objective clear - the user will upload a large file and must be redirected immediately to another page for proceeding different operations. But the file being large, will take time to be read from the controller's InputStream. So I unwillingly decided to fork a new Thread to handle this I/O. The code is as follows : The controller servlet /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse * response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub System.out.println("In Controller.doPost(...)"); TempModel tempModel = new TempModel(); tempModel.uploadSegYFile(request, response); System.out.println("Forwarding to Accepted.jsp"); /*try { Thread.sleep(1000 * 60); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); }*/ request.getRequestDispatcher("/jsp/Accepted.jsp").forward(request, response); } The model class package com.model; import java.io.IOException; import java.util.concurrent.ExecutionException; import java.util.concurrent.Future; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.utils.ProcessUtils; public class TempModel { public void uploadSegYFile(HttpServletRequest request, HttpServletResponse response) { // TODO Auto-generated method stub System.out.println("In TempModel.uploadSegYFile(...)"); /* * Trigger the upload/processing code in a thread, return immediately * and notify when the thread completes */ try { FileUploaderRunnable fileUploadRunnable = new FileUploaderRunnable( request.getInputStream()); /* * Future<FileUploaderRunnable> future = ProcessUtils.submitTask( * fileUploadRunnable, fileUploadRunnable); * * FileUploaderRunnable processed = future.get(); * * System.out.println("Is file uploaded : " + * processed.isFileUploaded()); */ Thread uploadThread = new Thread(fileUploadRunnable); uploadThread.start(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } /* * catch (InterruptedException e) { // TODO Auto-generated catch block * e.printStackTrace(); } catch (ExecutionException e) { // TODO * Auto-generated catch block e.printStackTrace(); } */ System.out.println("Returning from TempModel.uploadSegYFile(...)"); } } The Runnable package com.model; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.nio.ByteBuffer; import java.nio.channels.Channels; import java.nio.channels.ReadableByteChannel; public class FileUploaderRunnable implements Runnable { private boolean isFileUploaded = false; private InputStream inputStream = null; public FileUploaderRunnable(InputStream inputStream) { // TODO Auto-generated constructor stub this.inputStream = inputStream; } public void run() { // TODO Auto-generated method stub /* Read from InputStream. If success, set isFileUploaded = true */ System.out.println("Starting upload in a thread"); File outputFile = new File("D:/06c01_output.seg");/* * This will be changed * later */ FileOutputStream fos; ReadableByteChannel readable = Channels.newChannel(inputStream); ByteBuffer buffer = ByteBuffer.allocate(1000000); try { fos = new FileOutputStream(outputFile); while (readable.read(buffer) != -1) { fos.write(buffer.array()); buffer.clear(); } fos.flush(); fos.close(); readable.close(); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.println("File upload thread completed"); } public boolean isFileUploaded() { return isFileUploaded; } } My queries/doubts : Spawning threads manually from the Servlet makes sense to me logically but scares me coding wise - the container isn't aware of these threads after all(I think so!) The current code is giving an Exception which is quite obvious - the stream is inaccessible as the doPost(...) method returns before the run() method completes : In Controller.doPost(...) In TempModel.uploadSegYFile(...) Returning from TempModel.uploadSegYFile(...) Forwarding to Accepted.jsp Starting upload in a thread Exception in thread "Thread-4" java.lang.NullPointerException at org.apache.coyote.http11.InternalInputBuffer.fill(InternalInputBuffer.java:512) at org.apache.coyote.http11.InternalInputBuffer.fill(InternalInputBuffer.java:497) at org.apache.coyote.http11.InternalInputBuffer$InputStreamInputBuffer.doRead(InternalInputBuffer.java:559) at org.apache.coyote.http11.AbstractInputBuffer.doRead(AbstractInputBuffer.java:324) at org.apache.coyote.Request.doRead(Request.java:422) at org.apache.catalina.connector.InputBuffer.realReadBytes(InputBuffer.java:287) at org.apache.tomcat.util.buf.ByteChunk.substract(ByteChunk.java:407) at org.apache.catalina.connector.InputBuffer.read(InputBuffer.java:310) at org.apache.catalina.connector.CoyoteInputStream.read(CoyoteInputStream.java:202) at java.nio.channels.Channels$ReadableByteChannelImpl.read(Unknown Source) at com.model.FileUploaderRunnable.run(FileUploaderRunnable.java:39) at java.lang.Thread.run(Unknown Source) Keeping in mind the point 1., does the use of Executor framework help me in anyway ? package com.utils; import java.util.concurrent.Future; import java.util.concurrent.ScheduledThreadPoolExecutor; public final class ProcessUtils { /* Ensure that no more than 2 uploads,processing req. are allowed */ private static final ScheduledThreadPoolExecutor threadPoolExec = new ScheduledThreadPoolExecutor( 2); public static <T> Future<T> submitTask(Runnable task, T result) { return threadPoolExec.submit(task, result); } } So how should I ensure that the user doesn't block and the stream remains accessible so that the (uploaded)file can be read from it?

    Read the article

  • C# thread safety for class instances

    - by Steveng
    I am learning C# and I am confused with the thread safety of the copies of the class instances as below: eg: classA objA; classA objB = objA; objA.field1 = value2; //do I need lock around modification of field1? //let say we pass the objB to another thread objB.field1 = value1 //do I need a lock for objB because of the modification of field1? I am confused because coming from the background of C++, the class in C# is the reference type. If both objA and objB refer to the same memory underlying, then I would need a lock to protect the simultaneous writing to the field1. Could someone confirm with this or am I missing something? Thanks.

    Read the article

  • Java concurrency - Should block or yield?

    - by teto
    Hi, I have multiple threads each one with its own private concurrent queue and all they do is run an infinite loop retrieving messages from it. It could happen that one of the queues doesn't receive messages for a period of time (maybe a couple seconds), and also they could come in big bursts and fast processing is necessary. I would like to know what would be the most appropriate to do in the first case: use a blocking queue and block the thread until I have more input or do a Thread.yield()? I want to have as much CPU resources available as possible at a given time, as the number of concurrent threads may increase with time, but also I don't want the message processing to fall behind, as there is no guarantee of when the thread will be reescheduled for execution when doing a yield(). I know that hardware, operating system and other factors play an important role here, but setting that aside and looking at it from a Java (JVM?) point of view, what would be the most optimal?

    Read the article

  • Advanced Registry Monitoring

    - by RyanTimmons91
    I'm attempting to create a small utility to watch for the creation (or modification) of a specific registry key, and to kill the process responsible for causing that registry modification. I have had success in watching the changes to the registry via a class called 'RegistryMonitor', however it does not give you any information on what process initiated the registry call, through some googling I found that a library called 'EasyHook' should be able to do what I want, but all the documentation states that its designed for a per-application hook. The program itself is a temporary security patch, until our vendors come out with an official security update. As best I can tell there isn't a way to do exactly what I want to accomplish from C#, which is the only language I can comfortable write, test and execute software in. Any help on this would be appreciated I'm considering watching the registry changes via the program I already have, then if the change is discovered (the pc is already infected) running RKill and locking down the PC to prevent the issue from getting any worse

    Read the article

  • Performance issues when using SSD for a developer notebook (WAMP/LAMP stack)?

    - by András Szepesházi
    I'm a web application developer using my notebook as a standalone development environment (WAMP stack). I just switched from a Core2-duo Vista 32 bit notebook with 2Gb RAM and SATA HDD, to an i5-2520M Win7 64 bit with 4Gb RAM and 128 GB SDD (Corsair P3 128). My initial experience was what I expected, fast boot, quick load of all the applications (Eclipse takes now 5 seconds as opposed to 30s on my old notebook), overall great experience. Then I started to build up my development stack, both as LAMP (using VirtualBox with a debian guest) and WAMP (windows native apache + mysql + php). I wanted to compare those two. This still all worked great out, then I started to pull in my projects to these stacks. And here came the nasty surprise, one of those projects produced a lot worse response times than on my old notebook (that was true for both the VirtualBox and WAMP stack). Apache, php and mysql configurations were practically identical in all environments. I started to do a lot of benchmarking and profiling, and here is what I've found: All general benchmarks (Performance Test 7.0, HDTune Pro, wPrime2 and some more) gave a big advantage to the new notebook. Nothing surprising here. Disc specific tests showed that read/write operations peaked around 380M/160M for the SSD, and all the different sized block operations also performed very well. Started apache performance benchmarking with Apache Benchmark for a small static html file (10 concurrent threads, 500 iterations). Old notebook: min 47ms, median 111ms, max 156ms New WAMP stack: min 71ms, median 135ms, max 296ms New LAMP stack (in VirtualBox): min 6ms, median 46ms, max 175ms Right here I don't get why the native WAMP stack performed so bad, but at least the LAMP environment brought the expected speed. Apache performance measurement for non-cached php content. The php runs a loop of 1000 and generates sha1(uniqid()) inisde. Again, 10 concurrent threads, 500 iterations were used for the benchmark. Old notebook: min 0ms, median 39ms, max 218ms New WAMP stack: min 20ms, median 61ms, max 186ms New LAMP stack (in VirtualBox): min 124ms, median 704ms, max 2463ms What the hell? The new LAMP performed miserably, and even the new native WAMP was outperformed by the old notebook. php + mysql test. The test consists of connecting to a database and reading a single record form a table using INNER JOIN on 3 more (indexed) tables, repeated 100 times within a loop. Databases were identical. 10 concurrent threads, 100 iterations were used for the benchmark. Old notebook: min 1201ms, median 1734ms, max 3728ms New WAMP stack: min 367ms, median 675ms, max 1893ms New LAMP stack (in VirtualBox): min 1410ms, median 3659ms, max 5045ms And the same test with concurrency set to 1 (instead of 10): Old notebook: min 1201ms, median 1261ms, max 1357ms New WAMP stack: min 399ms, median 483ms, max 539ms New LAMP stack (in VirtualBox): min 285ms, median 348ms, max 444ms Strictly for my purposes, as I'm using a self contained development environment (= low concurrency) I could be satisfied with the second test's result. Though I have no idea why the VirtualBox environment performed so bad with higher concurrency. Finally I performed a test of including many php files. The application that I mentioned at the beginning, the one that was performing so bad, has a heavy bootstrap, loads hundreds of small library and configuration files while initializing. So this test does nothing else just includes about 100 files. Concurrency set to 1, 100 iterations: Old notebook: min 140ms, median 168ms, max 406ms New WAMP stack: min 434ms, median 488ms, max 604ms New LAMP stack (in VirtualBox): min 413ms, median 1040ms, max 1921ms Even if I consider that VirtualBox reached those files via shared folders, and that slows things down a bit, I still don't see how could the old notebook outperform so heavily both new configurations. And I think this is the real root of the slow performance, as the application uses even more includes, and the whole bootstrap will occur several times within a page request (for each ajax call, for example). To sum it up, here I am with a brand new high-performance notebook that loads the same page in 20 seconds, that my old notebook can do in 5-7 seconds. Needless to say, I'm not a very happy person right now. Why do you think I experience these poor performance values? What are my options to remedy this situation?

    Read the article

  • SBS2003 to SBS2011 Migration - Installation Error

    - by Shawn Gradwell
    Microsoft Small Business Server 2003 to 2011 Migration. I followed the Migration Guide from Microsoft and the source server had no errors when running the various tests prior to the migration. I have completed the destination server setup using the Answer File and the server is up and running. It all looks good, I can access Exchange and AD and the only problem is the error message when you log in stating that the setup did not complete and to check the logs. Because all looks good I am continuing the migration to the destination server. I also have to state that this client does not use Sharepoint at all. Do I have to redo everything? Herewith the logs: [4992] 121016.225454.5905: Task: Starting Add User or Group access VSS registry. [4992] 121016.225454.7645: TaskManagement: In TaskScheduler.RunTasks(): The "ConfigureSharePointVSSRegistryTask" Task threw an Exception during the Run() call:System.Security.Principal.IdentityNotMappedException: Some or all identity references could not be translated. at System.Security.Principal.NTAccount.Translate(IdentityReferenceCollection sourceAccounts, Type targetType, Boolean forceSuccess) at System.Security.Principal.NTAccount.Translate(Type targetType) at System.Security.AccessControl.CommonObjectSecurity.ModifyAccess(AccessControlModification modification, AccessRule rule, Boolean& modified) at System.Security.AccessControl.CommonObjectSecurity.AddAccessRule(AccessRule rule) at Microsoft.WindowsServerSolutions.IWorker.Tasks.ConfigureSharePointVSSRegistryTask.AddUsersToAccessRegistry(List`1 names) at Microsoft.WindowsServerSolutions.IWorker.Tasks.ConfigureSharePointVSSRegistryTask.Run(ITaskDataLink dl) at Microsoft.WindowsServerSolutions.TaskManagement.Data.Task.Run(ITaskDataLink dataLink) at Microsoft.WindowsServerSolutions.TaskManagement.TaskScheduler.RunTasks(String taskListId, String stateFileName) [4992] 121016.225454.7655: Setup: An error was encountered on the TME thread: System.Security.Principal.IdentityNotMappedException: Some or all identity references could not be translated. at System.Security.Principal.NTAccount.Translate(IdentityReferenceCollection sourceAccounts, Type targetType, Boolean forceSuccess) at System.Security.Principal.NTAccount.Translate(Type targetType) at System.Security.AccessControl.CommonObjectSecurity.ModifyAccess(AccessControlModification modification, AccessRule rule, Boolean& modified) at System.Security.AccessControl.CommonObjectSecurity.AddAccessRule(AccessRule rule) at Microsoft.WindowsServerSolutions.IWorker.Tasks.ConfigureSharePointVSSRegistryTask.AddUsersToAccessRegistry(List`1 names) at Microsoft.WindowsServerSolutions.IWorker.Tasks.ConfigureSharePointVSSRegistryTask.Run(ITaskDataLink dl) at Microsoft.WindowsServerSolutions.TaskManagement.Data.Task.Run(ITaskDataLink dataLink) at Microsoft.WindowsServerSolutions.TaskManagement.TaskScheduler.RunTasks(String taskListId, String stateFileName) at Microsoft.WindowsServerSolutions.Setup.SBSSetup.ProgressPagePresenter._RunTasks(Object sender, DoWorkEventArgs e) [4956] 121016.225455.0685: Setup: _UnhandledExceptionHandler: Setup encountered an error: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.Reflection.TargetInvocationException: The TME thread failed (see the inner exception). ---> System.Security.Principal.IdentityNotMappedException: Some or all identity references could not be translated. at System.Security.Principal.NTAccount.Translate(IdentityReferenceCollection sourceAccounts, Type targetType, Boolean forceSuccess) at System.Security.Principal.NTAccount.Translate(Type targetType) at System.Security.AccessControl.CommonObjectSecurity.ModifyAccess(AccessControlModification modification, AccessRule rule, Boolean& modified) at System.Security.AccessControl.CommonObjectSecurity.AddAccessRule(AccessRule rule) at Microsoft.WindowsServerSolutions.IWorker.Tasks.ConfigureSharePointVSSRegistryTask.AddUsersToAccessRegistry(List`1 names) at Microsoft.WindowsServerSolutions.IWorker.Tasks.ConfigureSharePointVSSRegistryTask.Run(ITaskDataLink dl) at Microsoft.WindowsServerSolutions.TaskManagement.Data.Task.Run(ITaskDataLink dataLink) at Microsoft.WindowsServerSolutions.TaskManagement.TaskScheduler.RunTasks(String taskListId, String stateFileName) at Microsoft.WindowsServerSolutions.Setup.SBSSetup.ProgressPagePresenter._RunTasks(Object sender, DoWorkEventArgs e) at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument) --- End of inner exception stack trace --- at Microsoft.WindowsServerSolutions.Setup.SBSSetup.ProgressPagePresenter.TasksCompleted(Object sender, RunWorkerCompletedEventArgs e) --- End of inner exception stack trace --- at System.RuntimeMethodHandle._InvokeMethodFast(IRuntimeMethodInfo method, Object target, Object[] arguments, SignatureStruct& sig, MethodAttributes methodAttributes, RuntimeType typeOwner) at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, Boolean skipVisibilityChecks) at System.Delegate.DynamicInvokeImpl(Object[] args) at System.Windows.Forms.Control.InvokeMarshaledCallbackDo(ThreadMethodEntry tme) at System.Windows.Forms.Control.InvokeMarshaledCallbackHelper(Object obj) at System.Threading.ExecutionContext.runTryCode(Object userData) at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state) at System.Windows.Forms.Control.InvokeMarshaledCallback(ThreadMethodEntry tme) at System.Windows.Forms.Control.InvokeMarshaledCallbacks() at System.Windows.Forms.Control.WndProc(Message& m) at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg) at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData) at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context) at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context) at Microsoft.WindowsServerSolutions.Common.Wizards.Framework.WizardChainEngine.Launch() at Microsoft.WindowsServerSolutions.Setup.SBSSetup.MainClass._LaunchWizard() at Microsoft.WindowsServerSolutions.Setup.SBSSetup.MainClass.RealMain(String[] args) at Microsoft.WindowsServerSolutions.Setup.SBSSetup.MainClass.Main(String[] args) [4956] 121016.225455.0865: Setup: Removed the password. [4956] 121016.225455.0905: Setup: Deleting scheduled task at path Microsoft\Windows\Windows Small Business Server 2011 Standard with name Setup [4956] 121016.225455.8055: Setup: Removed SBSSetup from the RunOnce.

    Read the article

< Previous Page | 17 18 19 20 21 22 23 24 25 26 27 28  | Next Page >