Examples with IndexingComponent org.apache.stanbol.entityhub.indexing.core.IndexingComponent used on opensource projects

Example 1 with IndexingComponent

use of org.apache.stanbol.entityhub.indexing.core.IndexingComponent in project stanbol by apache.

the class IndexerImpl method initialiseIndexing.

@Override
public void initialiseIndexing() {
    synchronized (stateSync) {
        //initialisation at the same time ...
        if (getState() != State.UNINITIALISED) {
            return;
        }
        setState(State.INITIALISING);
        log.info("{}: initialisation started ...", name);
    }
    //add all IndexingSources that need to be initialised to a set
    final Collection<IndexingComponent> toInitialise = new HashSet<IndexingComponent>();
    //we need an simple listener that removes the IndexingSerouces from the
    //above list
    final IndexingSourceInitialiserListener listener = new IndexingSourceInitialiserListener() {

        @Override
        public void indexingSourceInitialised(IndexingSourceEventObject eventObject) {
            //remove the IndexingSource from the toInitialise set
            synchronized (toInitialise) {
                toInitialise.remove(eventObject.getIndexingSource());
                if (toInitialise.isEmpty()) {
                    //if no more left to initialise
                    //notify others about it
                    toInitialise.notifyAll();
                }
            }
            //finally remove this listener
            eventObject.getSource().removeIndexingSourceInitialiserListener(this);
        }
    };
    //Indexing Sources in their own Thread
    for (IndexingComponent source : indexingComponents) {
        if (source.needsInitialisation()) {
            //if it need to be initialised
            // add it to the list
            toInitialise.add(source);
            //create an initialiser
            IndexingSourceInitialiser initialiser = new IndexingSourceInitialiser(source);
            //add the listener
            initialiser.addIndexingSourceInitialiserListener(listener);
            //create and init the Thread
            Thread thread = new Thread(initialiser);
            thread.setDaemon(true);
            thread.start();
        }
    //else no initialisation is needed
    }
    //now wait until all IndexingSources are initialised!
    while (!toInitialise.isEmpty()) {
        synchronized (toInitialise) {
            if (!toInitialise.isEmpty()) {
                try {
                    toInitialise.wait();
                } catch (InterruptedException e) {
                //year looks like all IndexingSources are initialised!
                }
            }
        }
    }
    //initialise the stream used to write the ids of indexed entities
    try {
        indexedEntityIdOutputStream = getEntityIdFileOutputStream();
    } catch (IOException e) {
        if (entityPostProcessors != null) {
            throw new IllegalStateException("Unable to open stream for writing" + "the IDs of indexed Entities as required for post-" + "processing!", e);
        } else {
            log.warn("Unable to open stream for writing the Ids of indexed " + "Entities -> indexes entity Ids will not be available!", e);
        }
    }
    log.info("initialisation completed for {}", name);
    setState(State.INITIALISED);
}