fixes for Meter Service

Change-Id: I83d5b8a2e0a955c050f7afe96761d5709d4f9f18
diff --git a/core/api/src/main/java/org/onosproject/net/meter/MeterId.java b/core/api/src/main/java/org/onosproject/net/meter/MeterId.java
index f479ac5..872de2d 100644
--- a/core/api/src/main/java/org/onosproject/net/meter/MeterId.java
+++ b/core/api/src/main/java/org/onosproject/net/meter/MeterId.java
@@ -32,7 +32,7 @@
     public static final MeterId ALL = new MeterId(0xFFFFFFFF);
 
     private MeterId(long id) {
-        checkArgument(id <= MAX, "id cannot be larger than 0xFFFF0000");
+        checkArgument(id >= MAX, "id cannot be larger than 0xFFFF0000");
         this.id = id;
     }
 
@@ -65,6 +65,11 @@
         return Long.hashCode(id);
     }
 
+    @Override
+    public String toString() {
+        return Long.toHexString(this.id);
+    }
+
     public static MeterId meterId(long id) {
         return new MeterId(id);