Moved AbstractWebResource to api bundle so it is accessible by applications.

Change-Id: Iddfe8a7d42d432e09424cede04b6c847198a9c85
diff --git a/web/api/src/main/java/org/onosproject/rest/resources/PathsWebResource.java b/web/api/src/main/java/org/onosproject/rest/resources/PathsWebResource.java
new file mode 100644
index 0000000..a97a933
--- /dev/null
+++ b/web/api/src/main/java/org/onosproject/rest/resources/PathsWebResource.java
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.rest.resources;
+
+import java.util.Set;
+
+import javax.ws.rs.GET;
+import javax.ws.rs.Path;
+import javax.ws.rs.PathParam;
+import javax.ws.rs.Produces;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.ElementId;
+import org.onosproject.net.HostId;
+import org.onosproject.net.topology.PathService;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onosproject.rest.AbstractWebResource;
+
+/**
+ * REST resource for interacting with path calculations.
+ */
+@Path("paths")
+public class PathsWebResource extends AbstractWebResource {
+
+    // Host id format is 00:00:00:00:00:01/-1
+    private static final int VLAN_SEPARATOR_OFFSET = 17;
+    private static final int FIRST_MAC_ADDRESS_SEPARATOR_OFFSET = 2;
+    private static final int SECOND_MAC_ADDRESS_SEPARATOR_OFFSET = 5;
+    private static final int THIRD_MAC_ADDRESS_SEPARATOR_OFFSET = 8;
+
+    /**
+     * Determines if the id appears to be the id of a host.
+     *
+     * @param id id string
+     * @return HostId if the id is valid, null otherwise
+     */
+    private HostId isHostId(String id) {
+
+        if (id.length() < VLAN_SEPARATOR_OFFSET + 1 ||
+            id.charAt(FIRST_MAC_ADDRESS_SEPARATOR_OFFSET) != ':' ||
+            id.charAt(SECOND_MAC_ADDRESS_SEPARATOR_OFFSET) != ':' ||
+            id.charAt(THIRD_MAC_ADDRESS_SEPARATOR_OFFSET) != ':' ||
+            id.charAt(VLAN_SEPARATOR_OFFSET) != '/') {
+            return null;
+        }
+
+        return HostId.hostId(id);
+    }
+
+    /**
+     * Gets the paths between two elements.
+     *
+     * @param src source
+     * @param dst destination
+     * @return path data
+     */
+    @GET
+    @Produces(MediaType.APPLICATION_JSON)
+    @Path("{src}/{dst}")
+    public Response getPath(@PathParam("src") String src,
+                            @PathParam("dst") String dst) {
+        PathService pathService = get(PathService.class);
+
+        ElementId srcElement = isHostId(src);
+        ElementId dstElement = isHostId(dst);
+
+        if (srcElement == null) {
+            // Doesn't look like a host, assume it is a device
+            srcElement = DeviceId.deviceId(src);
+        }
+
+        if (dstElement == null) {
+            // Doesn't look like a host, assume it is a device
+            dstElement = DeviceId.deviceId(dst);
+        }
+
+        Set<org.onosproject.net.Path> paths =
+                pathService.getPaths(srcElement, dstElement);
+        ObjectNode root =
+                    encodeArray(org.onosproject.net.Path.class, "paths", paths);
+        return ok(root).build();
+    }
+
+}