small javadoc improvements

git-svn-id: https://svn.apache.org/repos/asf/lucene/java/trunk@295101 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/lucene/search/IndexSearcher.java

@@ -29,6 +29,9 @@ import org.apache.lucene.index.Term;
  * <p>Applications usually need only call the inherited {@link #search(Query)}
  * or {@link #search(Query,Filter)} methods. For performance reasons it is 
  * recommended to open only one IndexSearcher and use it for all of your searches.
+ * 
+ * <p>Note that you can only access Hits from an IndexSearcher as long as it is
+ * not yet closed, otherwise an IOException will be thrown. 
  */
 public class IndexSearcher extends Searcher {
   IndexReader reader;

src/java/org/apache/lucene/search/Searcher.java

@@ -21,7 +21,10 @@ import java.io.IOException;
 import org.apache.lucene.index.Term;
 
 /** An abstract base class for search implementations.
- * Implements some common utility methods.
+ * Implements the main search methods.
+ * 
+ * <p>Note that you can only access Hits from a Searcher as long as it is
+ * not yet closed, otherwise an IOException will be thrown. 
  */
 public abstract class Searcher implements Searchable {