CORD Subscriber GUI - Created XosManagerRestUtils (based on OnosXOSIntegrationManager).
 - refactored XosManager appropriately.

Change-Id: I34c4627b5f5b55f56b46ead65e7da8b16bf07e54
diff --git a/apps/demo/cord-gui/src/main/java/org/onosproject/cord/gui/XosManagerRestUtils.java b/apps/demo/cord-gui/src/main/java/org/onosproject/cord/gui/XosManagerRestUtils.java
new file mode 100644
index 0000000..b8e8a4c
--- /dev/null
+++ b/apps/demo/cord-gui/src/main/java/org/onosproject/cord/gui/XosManagerRestUtils.java
@@ -0,0 +1,233 @@
+/*
+ * 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.cord.gui;
+
+import com.sun.jersey.api.client.Client;
+import com.sun.jersey.api.client.ClientHandlerException;
+import com.sun.jersey.api.client.ClientResponse;
+import com.sun.jersey.api.client.WebResource;
+import com.sun.jersey.api.client.filter.HTTPBasicAuthFilter;
+import org.slf4j.Logger;
+
+import static com.google.common.net.MediaType.JSON_UTF_8;
+import static java.net.HttpURLConnection.*;
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Utility RESTful methods for dealing with the XOS server.
+ */
+public class XosManagerRestUtils {
+    private static final String TEST_XOS_SERVER_ADDRESS = "10.254.1.22";
+    private static final int TEST_XOS_SERVER_PORT = 8000;
+    private static final String XOSLIB = "/xoslib";
+    private static final String AUTH_USER = "padmin@vicci.org";
+    private static final String AUTH_PASS = "letmein";
+
+    private static final String UTF_8 = JSON_UTF_8.toString();
+
+    private final Logger log = getLogger(getClass());
+
+    private final String xosServerAddress;
+    private final int xosServerPort;
+    private final String baseUri;
+
+    /**
+     * Constructs a utility class for the default server address and port,
+     * using the given base URI.
+     * <p>
+     * Note that the uri should start and end with a slash; for example:
+     * {@code "/volttenant/"}. This example would result in URIs of the form:
+     * <pre>
+     *     "http://10.254.1.22:8000/xoslib/volttenant/"
+     * </pre>
+     *
+     * @param baseUri base URI
+     */
+    public XosManagerRestUtils(String baseUri) {
+        this(TEST_XOS_SERVER_ADDRESS, TEST_XOS_SERVER_PORT, baseUri);
+    }
+
+    /**
+     * Constructs a utility class, using the supplied server address and port,
+     * using the given base URI.
+     * <p>
+     * Note that the uri should start and end with a slash; for example:
+     * {@code "/volttenant/"}. This example would result in URIs of the form:
+     * <pre>
+     *     "http://[server]:[port]/xoslib/volttenant/"
+     * </pre>
+     *
+     * @param xosServerAddress server IP address
+     * @param xosServerPort server port
+     * @param baseUri base URI
+     */
+    public XosManagerRestUtils(String xosServerAddress, int xosServerPort,
+                               String baseUri) {
+        this.xosServerAddress = xosServerAddress;
+        this.xosServerPort = xosServerPort;
+        this.baseUri = baseUri;
+    }
+
+    // build the base URL from the pieces we know...
+    private String baseUrl() {
+        return "http://" + xosServerAddress + ":" +
+                Integer.toString(xosServerPort) + XOSLIB + baseUri;
+    }
+
+    /**
+     * Gets a client web resource builder for the base XOS REST API
+     * with no additional URI.
+     *
+     * @return web resource builder
+     */
+    public WebResource.Builder getClientBuilder() {
+        return getClientBuilder("");
+    }
+
+    /**
+     * Gets a client web resource builder for the base XOS REST API
+     * with an optional additional URI.
+     *
+     * @param uri URI suffix to append to base URI
+     * @return web resource builder
+     */
+    public WebResource.Builder getClientBuilder(String uri) {
+        Client client = Client.create();
+        client.addFilter(new HTTPBasicAuthFilter(AUTH_USER, AUTH_PASS));
+        WebResource resource = client.resource(baseUrl() + uri);
+        return resource.accept(UTF_8).type(UTF_8);
+    }
+
+    /**
+     * Performs a REST GET operation on the base XOS REST URI.
+     *
+     * @return JSON string fetched by the GET operation
+     */
+    public String getRest() {
+        return getRest("");
+    }
+
+    /**
+     * Performs a REST GET operation on the base XOS REST URI with
+     * an optional additional URI.
+     *
+     * @param uri URI suffix to append to base URI
+     * @return JSON string fetched by the GET operation
+     */
+    public String getRest(String uri) {
+        WebResource.Builder builder = getClientBuilder(uri);
+        ClientResponse response = builder.get(ClientResponse.class);
+
+        if (response.getStatus() != HTTP_OK) {
+            log.info("REST GET request returned error code {}",
+                     response.getStatus());
+        }
+        String jsonString = response.getEntity(String.class);
+        log.info("JSON read:\n{}", jsonString);
+
+        return jsonString;
+    }
+
+    /**
+     * Performs a REST PUT operation on the base XOS REST URI.
+     *
+     * @return JSON string returned by the PUT operation
+     */
+    public String putRest() {
+        return putRest("");
+    }
+
+    /**
+     * Performs a REST PUT operation on the base XOS REST URI with
+     * an optional additional URI.
+     *
+     * @param uri URI suffix to append to base URI
+     * @return JSON string returned by the PUT operation
+     */
+    public String putRest(String uri) {
+        WebResource.Builder builder = getClientBuilder(uri);
+        ClientResponse response;
+
+        try {
+            response = builder.put(ClientResponse.class);
+        } catch (ClientHandlerException e) {
+            log.warn("Unable to contact REST server: {}", e.getMessage());
+            return "";
+        }
+
+        if (response.getStatus() != HTTP_OK) {
+            log.info("REST PUT request returned error code {}",
+                     response.getStatus());
+        }
+        String jsonString = response.getEntity(String.class);
+        log.info("JSON read:\n{}", jsonString);
+
+        return jsonString;
+    }
+
+    /**
+     * Performs a REST POST operation of a json string on the base
+     * XOS REST URI with an optional additional URI.
+     *
+     * @param json JSON string to post
+     */
+    public void postRest(String json) {
+        postRest("", json);
+    }
+
+    /**
+     * Performs a REST POST operation of a json string on the base
+     * XOS REST URI with an optional additional URI suffix.
+     *
+     * @param uri URI suffix to append to base URI
+     * @param json JSON string to post
+     */
+    public void postRest(String uri, String json) {
+        WebResource.Builder builder = getClientBuilder(uri);
+        ClientResponse response;
+
+        try {
+            response = builder.post(ClientResponse.class, json);
+        } catch (ClientHandlerException e) {
+            log.warn("Unable to contact REST server: {}", e.getMessage());
+            return;
+        }
+
+        if (response.getStatus() != HTTP_CREATED) {
+            log.info("REST POST request returned error code {}",
+                     response.getStatus());
+        }
+    }
+
+    /**
+     * Performs a REST DELETE operation on the base
+     * XOS REST URI with an optional additional URI.
+     *
+     * @param uri URI suffix to append to base URI
+     */
+    public void deleteRest(String uri) {
+        WebResource.Builder builder = getClientBuilder(uri);
+        ClientResponse response = builder.delete(ClientResponse.class);
+
+        if (response.getStatus() != HTTP_NO_CONTENT) {
+            log.info("REST DELETE request returned error code {}",
+                     response.getStatus());
+        }
+    }
+
+}