Package org.eclipse.osgi.storage.bundlefile

Class MRUBundleFileList

java.lang.Object
org.eclipse.osgi.storage.bundlefile.MRUBundleFileList
All Implemented Interfaces:
EventDispatcher<Object,Object,BundleFile>
public class MRUBundleFileList extends Object implements EventDispatcher<Object,Object,BundleFile>
A simple/quick/small implementation of an MRU (Most Recently Used) list to keep track of open BundleFiles. The MRU will use the file limit specified by the property "osgi.bundlefile.limit" by default unless the MRU is constructed with a specific file limit.

  • Constructor Details

    • MRUBundleFileList

      public MRUBundleFileList(int fileLimit, org.eclipse.osgi.internal.debug.Debug debug)

  • Method Details

    • add

      public boolean add(BundleFile bundleFile)
      Adds a BundleFile which is about to be opened to the MRU list. If the number of open BundleFiles == the fileLimit then the least recently used BundleFile is closed.
      Parameters:
      bundleFile - the bundle file about to be opened.
      Returns:
      true if back pressure is needed

    • remove

      public boolean remove(BundleFile bundleFile)
      Removes a bundle file which is about to be closed
      Parameters:
      bundleFile - the bundle file about to be closed
      Returns:
      true if the bundleFile existed in the MRU; false otherwise

    • use

      public void use(BundleFile bundleFile)
      Increments the use stamp of a bundle file
      Parameters:
      bundleFile - the bundle file to increment the use stamp for

    • dispatchEvent

      public final void dispatchEvent(Object eventListener, Object listenerObject, int eventAction, BundleFile eventObject)
      Description copied from interface: EventDispatcher
      This method is called once for each listener. This method must cast the event listener object to the appropriate listener class for the event type and call the appropriate listener method.

      The method should properly log/handle any exceptions thrown by the called listener. The EventManager will ignore any Throwable thrown by this method in order to continue delivery of the event to the next listener.

      Specified by:
      dispatchEvent in interface EventDispatcher<Object,Object,BundleFile>
      Parameters:
      eventListener - This is the key in the Map.Entry for the listener. The implementation of this method must cast it to the appropriate listener class for the event to be delivered and the appropriate listener method must then be called.
      listenerObject - This is the value in the Map.Entry for the listener.
      eventAction - This value was passed to the ListenerQueue object via one of its dispatchEvent* method calls. It can provide information (such as which listener method to call) so that the EventDispatcher can complete the delivery of the event to the listener.
      eventObject - This object was passed to the ListenerQueue object via one of its dispatchEvent* method calls. This object was created by the event source and is passed to this method. It should contain all the necessary information (such as what event object to pass) so that this method can complete the delivery of the event to the listener. This is typically the actual event object.

    • applyBackpressure

      public void applyBackpressure()

    • shutdown

      public void shutdown()
      Closes the bundle file closer thread for the MRU list

    • isClosing

      public boolean isClosing(BundleFile bundleFile)
      Returns true if this MRUBundleFileList is currently closing the specified bundle file on the current thread.
      Parameters:
      bundleFile - the bundle file
      Returns:
      true if the bundle file is being closed on the current thread

    • isEnabled

      public boolean isEnabled()