FileAnnotationCache.java

package org.jabref.logic.pdf;

import java.util.List;
import java.util.Map;

import org.jabref.model.database.BibDatabaseContext;
import org.jabref.model.entry.BibEntry;
import org.jabref.model.pdf.FileAnnotation;

import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class FileAnnotationCache {

    private static final Log LOGGER = LogFactory.getLog(FileAnnotation.class);
    //cache size in entries
    private final static int CACHE_SIZE = 10;

    //the inner list holds the annotations per file, the outer collection maps this to a BibEntry.
    private LoadingCache<BibEntry, Map<String, List<FileAnnotation>>> annotationCache;

    public FileAnnotationCache(BibDatabaseContext context) {
        annotationCache = CacheBuilder.newBuilder().maximumSize(CACHE_SIZE).build(new CacheLoader<BibEntry, Map<String, List<FileAnnotation>>>() {
            @Override
            public Map<String, List<FileAnnotation>> load(BibEntry entry) throws Exception {
                return new EntryAnnotationImporter(entry).importAnnotationsFromFiles(context);
            }
        });
    }

    /**
     * Note that entry becomes the most recent entry in the cache
     *
     * @param entry entry for which to get the annotations
     * @return Map containing a list of annotations in a list for each file
     */
    public Map<String, List<FileAnnotation>> getFromCache(BibEntry entry) {
        LOGGER.debug(String.format("Loading Bibentry '%s' from cache.", entry.getField(BibEntry.KEY_FIELD).get()));
        return annotationCache.getUnchecked(entry);
    }

    public void remove(BibEntry entry) {
        LOGGER.debug(String.format("Deleted Bibentry '%s' from cache.", entry.getField(BibEntry.KEY_FIELD).get()));
        annotationCache.invalidate(entry);
    }
}