Implement CLI commands to view and delete SR internal stores

sr-next-dst (renamed from sr-next-hops)
sr-next-port
sr-next-vlan
sr-next-mcast (renamed from sr-mcast-next)
sr-next-pw
sr-next-xconnect
sr-next-invalidate <next-id>

Change-Id: Id5178f786bb97e26ddb86015105dd19604ac0817
diff --git a/apps/segmentrouting/app/src/main/java/org/onosproject/segmentrouting/cli/XconnectNextListCommand.java b/apps/segmentrouting/app/src/main/java/org/onosproject/segmentrouting/cli/XconnectNextListCommand.java
new file mode 100644
index 0000000..f7a6b51
--- /dev/null
+++ b/apps/segmentrouting/app/src/main/java/org/onosproject/segmentrouting/cli/XconnectNextListCommand.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * 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.segmentrouting.cli;
+
+import org.apache.karaf.shell.commands.Command;
+import org.onosproject.cli.AbstractShellCommand;
+import org.onosproject.net.flowobjective.NextObjective;
+import org.onosproject.segmentrouting.xconnect.api.XconnectKey;
+import org.onosproject.segmentrouting.xconnect.api.XconnectService;
+
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.Map;
+
+/**
+ * Command to read the current state of the xconnect next stores.
+ */
+@Command(scope = "onos", name = "sr-next-xconnect",
+        description = "Displays the current next-id for xconnect")
+public class XconnectNextListCommand extends AbstractShellCommand {
+    @Override
+    protected void execute() {
+        XconnectService xconnectService =
+                AbstractShellCommand.get(XconnectService.class);
+        print(xconnectService.getNext());
+    }
+
+    private void print(Map<XconnectKey, NextObjective> nextStore) {
+        ArrayList<XconnectKey> a = new ArrayList<>(nextStore.keySet());
+        a.sort(Comparator
+                .comparing((XconnectKey o) -> o.deviceId().toString())
+                .thenComparing((XconnectKey o) -> o.vlanId().toShort()));
+
+        StringBuilder builder = new StringBuilder();
+        a.forEach(k ->
+            builder.append("\n")
+                    .append(k)
+                    .append(" --> ")
+                    .append(nextStore.get(k).id())
+        );
+        print(builder.toString());
+    }
+}