Class CachingLocalDataBuilder

java.lang.Object
fmpp.localdatabuilders.CachingLocalDataBuilder
All Implemented Interfaces:
LocalDataBuilder, ProgressListener
Direct Known Subclasses:
TddHashLocalDataBuilder

public abstract class CachingLocalDataBuilder extends Object implements LocalDataBuilder, ProgressListener
Stores the returned Map, and reuses it build(Engine, TemplateEnvironment) is invoked again during the same processing session. This is useful when the building of the local data is an expensive operation, and the builder is used for multiple source files.

The stored Map will be deleted at the end of the processing session.

  • Constructor Details

    • CachingLocalDataBuilder

      public CachingLocalDataBuilder()
  • Method Details

    • build

      public final Map build(Engine eng, TemplateEnvironment env) throws Exception
      Takes care of caching, and calls build(Engine) if no cached result is available.
      Specified by:
      build in interface LocalDataBuilder
      Returns:
      the variables to add to the local data. Can be null. The returned map will not be modified (although technically, badly behaved 3rd party code can modify the values soted in the map...).
      Throws:
      Exception
    • notifyProgressEvent

      public void notifyProgressEvent(Engine engine, int event, File src, int pMode, Throwable error, Object param) throws Exception
      Discards the cached result on ProgressListener.EVENT_END_PROCESSING_SESSION.

      The TemplateEnvironment is not passed, to ensure that the returned Map doesn't depend on the source file the builder is used for, so reusing the result for other source files is safe.

      Specified by:
      notifyProgressEvent in interface ProgressListener
      Parameters:
      engine - The engine instance where the event has occurred.
      event - The code of the event: an EVENT_... constant. As new event types can be introduced with new FMPP versions (even if it happens very seldom), a progress listener implementation should survive events that it does not understand. That is, it must not stop with an error, but it should silently ignore the event.
      src - Depending on event the source file or null.
      pMode - Depending on event the proccessing mode (Engine.PMODE_... constant) or Engine.PMODE_NONE. Note that new processing modes may be added as FMPP evolvers, so values that are not known be the progress listener should be handler nicely, and never cause error.
      error - The error, or null if there was no error.
      param - Extra information about the event. The class and meaning of object depends on the concrete event:
      • For EVENT_WARNING it is a String that describles the reason of warning.
      Throws:
      Exception
    • build

      protected abstract Map build(Engine eng) throws Exception
      Override this method in your local data builder class.
      Throws:
      Exception