SAMOA-58: A tentative solution to issue described in:

https://issues.apache.org/jira/browse/SAMOA-58
diff --git a/samoa-api/src/main/java/org/apache/samoa/streams/FileStream.java b/samoa-api/src/main/java/org/apache/samoa/streams/FileStream.java
index eece541..2998b22 100644
--- a/samoa-api/src/main/java/org/apache/samoa/streams/FileStream.java
+++ b/samoa-api/src/main/java/org/apache/samoa/streams/FileStream.java
@@ -80,7 +80,16 @@
 
   @Override
   public boolean hasMoreInstances() {
-    return !this.hitEndOfStream;
+    if (this.hitEndOfStream) {
+      if (getNextFileReader()) {
+        this.hitEndOfStream = false;
+        return hasMoreInstances();
+      } else {
+        return false;
+      }
+    } else {
+      return true;
+    }
   }
 
   @Override