Rework blocking command code.

Mostly remove the helper utils. The server is required to present the
client with a consisent state of the block list and corresponding
modifications, so we should not end up with duplicate entires if we
don't check for them.

SMACK-731

smack-extensions/src/main/java/org/jivesoftware/smackx/blocking/BlockingCommandManager.java

@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2016 Fernando Ramirez
+ * Copyright 2016 Fernando Ramirez, Florian Schmaus
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -44,6 +44,7 @@ import org.jxmpp.jid.Jid;
  * Blocking command manager class.
  * 
  * @author Fernando Ramirez
+ * @author Florian Schmaus
  * @see <a href="http://xmpp.org/extensions/xep-0191.html">XEP-0191: Blocking
  *      Command</a>
  */
@@ -96,7 +97,7 @@ public final class BlockingCommandManager extends Manager {
                         }
 
                         List<Jid> blockedJids = blockContactIQ.getJids();
-                        addToBlockList(blockedJids);
+                        blockListCached.addAll(blockedJids);
 
                         return IQ.createResultIQ(blockContactIQ);
                     }
@@ -117,7 +118,7 @@ public final class BlockingCommandManager extends Manager {
                 if (unblockedJids == null) { // remove all
                     blockListCached.clear();
                 } else { // remove only some
-                    removeFromBlockList(unblockedJids);
+                    blockListCached.removeAll(unblockedJids);
                 }
 
                 return IQ.createResultIQ(unblockContactIQ);
@@ -136,33 +137,6 @@ public final class BlockingCommandManager extends Manager {
         });
     }
 
-    private void addToBlockList(List<Jid> blockedJids) {
-        for (Jid jid : blockedJids) {
-            if (searchJid(jid) == -1) {
-                blockListCached.add(jid);
-            }
-        }
-    }
-
-    private void removeFromBlockList(List<Jid> unblockedJids) {
-        for (Jid jid : unblockedJids) {
-            int position = searchJid(jid);
-            if (position != -1) {
-                blockListCached.remove(position);
-            }
-        }
-    }
-
-    private int searchJid(Jid jid) {
-        int i = -1;
-        for (int j = 0; j < blockListCached.size(); j++) {
-            if (blockListCached.get(j).equals(jid)) {
-                i = j;
-            }
-        }
-        return i;
-    }
-
     /**
      * Returns true if Blocking Command is supported by the server.
      * 
@@ -197,8 +171,7 @@ public final class BlockingCommandManager extends Manager {
         BlockListIQ blockListIQResult = connection().createPacketCollectorAndSend(blockListIQ).nextResultOrThrow();
         blockListCached = blockListIQResult.getJids();
 
-        List<Jid> emptyList = Collections.emptyList();
+        return Collections.unmodifiableList(blockListCached);
-        return (blockListCached == null) ? emptyList : Collections.unmodifiableList(blockListCached);
     }
 
     /**
@@ -241,7 +214,7 @@ public final class BlockingCommandManager extends Manager {
      */
     public void unblockAll()
             throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
-        UnblockContactsIQ unblockContactIQ = new UnblockContactsIQ(null);
+        UnblockContactsIQ unblockContactIQ = new UnblockContactsIQ();
         connection().createPacketCollectorAndSend(unblockContactIQ).nextResultOrThrow();
     }
 

smack-extensions/src/main/java/org/jivesoftware/smackx/blocking/element/BlockListIQ.java

@@ -16,6 +16,7 @@
  */
 package org.jivesoftware.smackx.blocking.element;
 
+import java.util.Collections;
 import java.util.List;
 
 import org.jivesoftware.smack.packet.IQ;
@@ -50,6 +51,9 @@ public class BlockListIQ extends IQ {
      */
     public BlockListIQ(List<Jid> jids) {
         super(ELEMENT, NAMESPACE);
+        if (jids == null) {
+            jids = Collections.emptyList();
+        }
         this.jids = jids;
     }
 
@@ -71,10 +75,8 @@ public class BlockListIQ extends IQ {
 
     @Override
     protected IQChildElementXmlStringBuilder getIQChildElementBuilder(IQChildElementXmlStringBuilder xml) {
-
+        if (jids.isEmpty()) {
-        if (jids == null) {
             xml.setEmptyElement();
-
         } else {
             xml.rightAngleBracket();
 

smack-extensions/src/main/java/org/jivesoftware/smackx/blocking/element/UnblockContactsIQ.java

@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2016 Fernando Ramirez
+ * Copyright 2016 Fernando Ramirez, Florian Schmaus
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,6 +26,7 @@ import org.jxmpp.jid.Jid;
  * Unblock contact IQ class.
  * 
  * @author Fernando Ramirez
+ * @author Florian Schmaus
  * @see <a href="http://xmpp.org/extensions/xep-0191.html">XEP-0191: Blocking
  *      Command</a>
  */
@@ -54,6 +55,13 @@ public class UnblockContactsIQ extends IQ {
         this.jids = jids;
     }
 
+    /**
+     * Constructs a new unblock IQ which will unblock <b>all</b> JIDs. 
+     */
+    public UnblockContactsIQ() {
+        this(null);
+    }
+
     /**
      * Get the JIDs.
      * 

smack-extensions/src/main/java/org/jivesoftware/smackx/blocking/provider/BlockListIQProvider.java

@@ -21,9 +21,9 @@ import java.util.List;
 
 import org.jivesoftware.smack.packet.IQ.Type;
 import org.jivesoftware.smack.provider.IQProvider;
+import org.jivesoftware.smack.util.ParserUtils;
 import org.jivesoftware.smackx.blocking.element.BlockListIQ;
 import org.jxmpp.jid.Jid;
-import org.jxmpp.jid.impl.JidCreate;
 import org.xmlpull.v1.XmlPullParser;
 
 /**
@@ -49,7 +49,8 @@ public class BlockListIQProvider extends IQProvider<BlockListIQ> {
                     if (jids == null) {
                         jids = new ArrayList<>();
                     }
-                    jids.add(JidCreate.from(parser.getAttributeValue("", "jid")));
+                    Jid jid = ParserUtils.getJidAttribute(parser);
+                    jids.add(jid);
                 }
                 break;
 

smack-extensions/src/test/java/org/jivesoftware/smackx/blocking/GetBlockingListTest.java

@@ -53,7 +53,7 @@ public class GetBlockingListTest {
 
         IQ iq2 = (IQ) PacketParserUtils.parseStanza(emptyBlockListIQExample);
         BlockListIQ emptyBlockListIQ = (BlockListIQ) iq2;
-        Assert.assertNull(emptyBlockListIQ.getJids());
+        Assert.assertEquals(0, emptyBlockListIQ.getJids().size());
     }
 
 }