Sketched out changes to link resource service to support intent replacement mechanism.
diff --git a/core/api/src/main/java/org/onlab/onos/net/resource/LinkResourceService.java b/core/api/src/main/java/org/onlab/onos/net/resource/LinkResourceService.java
index 5ae5187..43cc61c 100644
--- a/core/api/src/main/java/org/onlab/onos/net/resource/LinkResourceService.java
+++ b/core/api/src/main/java/org/onlab/onos/net/resource/LinkResourceService.java
@@ -24,6 +24,16 @@
     void releaseResources(LinkResourceAllocations allocations);
 
     /**
+     * Updates previously made allocations with a new resource request.
+     *
+     * @param req            updated resource request
+     * @param oldAllocations old resource allocations
+     * @return new resource allocations
+     */
+    LinkResourceAllocations updateResources(LinkResourceRequest req,
+                                            LinkResourceAllocations oldAllocations);
+
+    /**
      * Returns all allocated resources.
      *
      * @return allocated resources
@@ -61,4 +71,15 @@
      * @return available resources for the target link
      */
     ResourceRequest getAvailableResources(Link link);
+
+    /**
+     * Returns available resources for given link.
+     *
+     * @param link        a target link
+     * @param allocations allocations to be included as available
+     * @return available resources for the target link
+     */
+    ResourceRequest getAvailableResources(Link link,
+                                          LinkResourceAllocations allocations);
+
 }
diff --git a/core/net/src/main/java/org/onlab/onos/net/resource/impl/LinkResourceManager.java b/core/net/src/main/java/org/onlab/onos/net/resource/impl/LinkResourceManager.java
index ad15f56..75e0818 100644
--- a/core/net/src/main/java/org/onlab/onos/net/resource/impl/LinkResourceManager.java
+++ b/core/net/src/main/java/org/onlab/onos/net/resource/impl/LinkResourceManager.java
@@ -79,6 +79,12 @@
     }
 
     @Override
+    public LinkResourceAllocations updateResources(LinkResourceRequest req,
+                                                   LinkResourceAllocations oldAllocations) {
+        return null;
+    }
+
+    @Override
     public Iterable<LinkResourceAllocations> getAllocations() {
         // TODO Auto-generated method stub
         return null;
@@ -108,4 +114,10 @@
         return null;
     }
 
+    @Override
+    public ResourceRequest getAvailableResources(Link link,
+                                                 LinkResourceAllocations allocations) {
+        return null;
+    }
+
 }