added a little doc

src/main/java/com/commafeed/backend/feeds/FaviconFetcher.java

@@ -81,7 +81,7 @@ public class FaviconFetcher {
 		return bytes;
 	}
 
-	boolean isValidIconResponse(byte[] content, String contentType) {
+	private boolean isValidIconResponse(byte[] content, String contentType) {
 		if (content == null) {
 			return false;
 		}

src/main/java/com/commafeed/backend/feeds/FeedRefreshExecutor.java

@@ -10,6 +10,11 @@ import java.util.concurrent.atomic.AtomicInteger;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+/**
+ * Wraps a {@link ThreadPoolExecutor} instance. Blocks when queue is full instead of rejecting the task. Allow priority queueing by using
+ * {@link Task} instead of {@link Runnable}
+ * 
+ */
 public class FeedRefreshExecutor {
 
 	private static Logger log = LoggerFactory.getLogger(FeedRefreshExecutor.class);

src/main/java/com/commafeed/backend/feeds/FeedRefreshTaskGiver.java

@@ -25,6 +25,11 @@ import com.google.api.client.util.Maps;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Queues;
 
+/**
+ * Infinite loop fetching feeds from the database and queuing them to the {@link FeedRefreshWorker} pool. Also handles feed database updates
+ * at the end of the cycle through {@link #giveBack(Feed)}.
+ * 
+ */
 @ApplicationScoped
 public class FeedRefreshTaskGiver {
 

src/main/java/com/commafeed/backend/feeds/FeedRefreshWorker.java

@@ -22,6 +22,10 @@ import com.commafeed.backend.model.FeedEntry;
 import com.commafeed.backend.services.ApplicationSettingsService;
 import com.sun.syndication.io.FeedException;
 
+/**
+ * Calls {@link FeedFetcher} and handles its outcome
+ * 
+ */
 @ApplicationScoped
 public class FeedRefreshWorker {
 

src/main/java/com/commafeed/backend/feeds/FeedUtils.java

@@ -36,6 +36,10 @@ import com.steadystate.css.parser.CSSOMParser;
 
 import edu.uci.ics.crawler4j.url.URLCanonicalizer;
 
+/**
+ * Utility methods related to feed handling
+ * 
+ */
 public class FeedUtils {
 
 	protected static Logger log = LoggerFactory.getLogger(FeedUtils.class);