- Removed isEmpty() Java 6 method, so Andrzej can compile Luke

git-svn-id: https://svn.apache.org/repos/asf/lucene/java/trunk@496628 13f79535-47bb-0310-9956-ffa450edef68

contrib/analyzers/src/java/org/apache/lucene/analysis/ngram/EdgeNGramTokenizer.java

@@ -88,7 +88,7 @@ public class EdgeNGramTokenizer extends Tokenizer {
   }
 
   static Side side(String label) {
-    if (label == null || label.isEmpty())
+    if (label == null || label.trim().length() == 0)
       throw new IllegalArgumentException("Label must be either 'front' or 'back'");
     if (label.equals("front"))
       return Side.FRONT;