Reverted constant accessors to be public again.

Change-Id: Iaae04eb4157350d7a16e7998eb3ed64082d158bd
diff --git a/core/api/src/main/java/org/onosproject/net/config/basics/BasicLinkConfig.java b/core/api/src/main/java/org/onosproject/net/config/basics/BasicLinkConfig.java
index 0ad851a..0e1e6d6 100644
--- a/core/api/src/main/java/org/onosproject/net/config/basics/BasicLinkConfig.java
+++ b/core/api/src/main/java/org/onosproject/net/config/basics/BasicLinkConfig.java
@@ -28,11 +28,11 @@
  */
 public final class BasicLinkConfig extends AllowedEntityConfig<LinkKey> {
 
-    private static final String TYPE = "type";
-    private static final String METRIC = "metric";
-    private static final String LATENCY = "latency";
-    private static final String BANDWIDTH = "bandwidth";
-    private static final String IS_DURABLE = "durable";
+    public static final String TYPE = "type";
+    public static final String METRIC = "metric";
+    public static final String LATENCY = "latency";
+    public static final String BANDWIDTH = "bandwidth";
+    public static final String IS_DURABLE = "durable";
 
     @Override
     public boolean isValid() {