Column Oriented Database from apache (Hadoop)

Running and debugging jetty maven plugin in Netbeans

Coding with Netbeans will make developer life simple. We don't need search for plugins and install different plugins from different places. Maven projects can opened as directly in Netbeans without any settings. Here is the way to run & debug using maven jetty plugin. We can't add Jetty server as servers in Netbeans. Run project: Right click on project and open the properties. click on "Actions" on left side. On right side there will be list of available actions. To run jetty can be created a new action or override default "Run Project" Here I am overriding default one, Because I can run the project just by hitting "F6" key click on "Run Project" Enter the value "Execute Goals" as "jetty:run", If you want run as offline add "jetty:run -o" "Active Profiles" can be empty In "set Properties" field we can set like skip test. Here I am skipping test. Done, After setting y...

Disable hibernate Optimistic Lock for specific scenario

Optimistic Lock gives more control on concurrent modification on data. That can be achieved very easily in hibernate using @Version column. But in some cases we may have to avoid concurrency check, example background process. To disable Optimistic lock set OptimisticLockMode as NONE for entity class while hibernate is initiating. We can't remove version column that needs Database changes and ORM changes. In this way we can disable Optimistic Lock by code. implement "org.hibernate.event.Initializable" interface override the below method. @Override public void initialize(Configuration cfg) { Iterator<?> persistentClassIterator = cfg.getClassMappings(); while (persistentClassIterator.hasNext()) { PersistentClass persistentClass = PersistentClass.class.cast(persistentClassIterato...

unlock the static files while jetty is running on windows.

When running a java maven web application in jetty on windows. All static files are locked and not able edit and save those files while jetty is running. This will eat developers time beacuse each and every change in javascript & css files, jetty have to re-started. Depends on application's dependencies that build will take more than 5minutes. Why jetty is locking the static files? Jetty buffers static content for webapps such as html files, css files, images etc and uses memory mapped files to do this if the NIO connectors are being used. The problem is that on Windows, memory mapping a file causes the file to be locked, so that the file cannot be updated or replaced. This means that effectively you have to stop Jetty in order to update a file Jetty provides a configuration switch in the webdefault.xml file for the DefaultServlet which enables or disables the use of memory mapped files. If you are running on Windows and are having file locking p...

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