Refactor PEP to use PubSub API.

Fixes SMACK-416.

smack-extensions/src/main/java/org/jivesoftware/smackx/disco/Feature.java

@@ -0,0 +1,41 @@
+/**
+ *
+ * Copyright 2015 Florian Schmaus
+ *
+ * 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.jivesoftware.smackx.disco;
+
+/**
+ * Utility class for Features.
+ *
+ * @author Florian Schmaus
+ *
+ */
+public class Feature {
+
+    public enum Support {
+        optional,
+        recommended,
+        required,
+        ;
+
+        public boolean isRequired() {
+            return this == required;
+        }
+
+        public boolean isNotRequired() {
+            return !isRequired();
+        }
+    }
+}

smack-extensions/src/main/java/org/jivesoftware/smackx/disco/ServiceDiscoveryManager.java

@@ -41,6 +41,8 @@ import org.jxmpp.util.cache.Cache;
 import org.jxmpp.util.cache.ExpirationCache;
 
 import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.LinkedList;
@@ -659,9 +661,20 @@ public final class ServiceDiscoveryManager extends Manager {
      * @throws InterruptedException 
      * @since 4.1
      */
-    public boolean serverSupportsFeature(String feature) throws NoResponseException, XMPPErrorException,
+    public boolean serverSupportsFeature(CharSequence feature) throws NoResponseException, XMPPErrorException,
                     NotConnectedException, InterruptedException {
-        return supportsFeature(connection().getXMPPServiceDomain(), feature);
+        return serverSupportsFeatures(feature);
+    }
+
+    public boolean serverSupportsFeatures(CharSequence... features) throws NoResponseException,
+                    XMPPErrorException, NotConnectedException, InterruptedException {
+        return serverSupportsFeatures(Arrays.asList(features));
+    }
+
+    public boolean serverSupportsFeatures(Collection<? extends CharSequence> features)
+                    throws NoResponseException, XMPPErrorException, NotConnectedException,
+                    InterruptedException {
+        return supportsFeatures(connection().getXMPPServiceDomain(), features);
     }
 
     /**
@@ -675,9 +688,22 @@ public final class ServiceDiscoveryManager extends Manager {
      * @throws NotConnectedException 
      * @throws InterruptedException 
      */
-    public boolean supportsFeature(Jid jid, String feature) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
+    public boolean supportsFeature(Jid jid, CharSequence feature) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
+        return supportsFeatures(jid, feature);
+    }
+
+    public boolean supportsFeatures(Jid jid, CharSequence... features) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
+        return supportsFeatures(jid, Arrays.asList(features));
+    }
+
+    public boolean supportsFeatures(Jid jid, Collection<? extends CharSequence> features) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
         DiscoverInfo result = discoverInfo(jid);
-        return result.containsFeature(feature);
+        for (CharSequence feature : features) {
+            if (!result.containsFeature(feature)) {
+                return false;
+            }
+        }
+        return true;
     }
 
     /**

smack-extensions/src/main/java/org/jivesoftware/smackx/disco/packet/DiscoverInfo.java

@@ -209,7 +209,7 @@ public class DiscoverInfo extends IQ implements TypedCloneable<DiscoverInfo> {
      * @param feature the feature to check
      * @return true if the requestes feature has been discovered
      */
-    public boolean containsFeature(String feature) {
+    public boolean containsFeature(CharSequence feature) {
         return features.contains(new Feature(feature));
     }
 
@@ -482,6 +482,10 @@ public class DiscoverInfo extends IQ implements TypedCloneable<DiscoverInfo> {
             this.variable = feature.variable;
         }
 
+        public Feature(CharSequence variable) {
+            this(variable.toString());
+        }
+
         /**
          * Creates a new feature offered by an XMPP entity or item.
          *