Add Stanza.setNewStanzaId() and ensureStanzaIdSet()

Also deprecate setStanzaId() since it was not clear if this would
create a new stanza ID or just ensure that one is set.

smack-core/src/main/java/org/jivesoftware/smack/packet/Stanza.java

@@ -138,9 +138,43 @@ public abstract class Stanza implements TopLevelStreamElement {
      *
      * @return the stanza id.
      * @since 4.2
+     * @deprecated use {@link #setNewStanzaId()} instead.
      */
+    @Deprecated
+    // TODO: Remove in Smack 4.5.
     public String setStanzaId() {
-        if (!hasStanzaIdSet()) {
+        return ensureStanzaIdSet();
+    }
+
+    /**
+     * Set a new stanza ID even if there is already one set.
+     *
+     * @return the stanza id.
+     * @since 4.4
+     */
+    public String setNewStanzaId() {
+        return ensureStanzaIdSet(true);
+    }
+
+    /**
+     * Ensure a stanza id is set.
+     *
+     * @return the stanza id.
+     * @since 4.4
+     */
+    public String ensureStanzaIdSet() {
+        return ensureStanzaIdSet(false);
+    }
+
+    /**
+     * Ensure that a stanza ID is set.
+     *
+     * @param forceNew force a new ID even if there is already one set.
+     * @return the stanza ID.
+     * @since 4.4
+     */
+    private String ensureStanzaIdSet(boolean forceNew) {
+        if (forceNew || !hasStanzaIdSet()) {
             setStanzaId(StanzaIdUtil.newStanzaId());
         }
         return getStanzaId();

smack-extensions/src/main/java/org/jivesoftware/smackx/receipts/DeliveryReceiptRequest.java

@@ -22,7 +22,6 @@ import org.jivesoftware.smack.packet.ExtensionElement;
 import org.jivesoftware.smack.packet.Message;
 import org.jivesoftware.smack.packet.Stanza;
 import org.jivesoftware.smack.packet.XmlEnvironment;
-import org.jivesoftware.smack.packet.id.StanzaIdUtil;
 import org.jivesoftware.smack.provider.ExtensionElementProvider;
 import org.jivesoftware.smack.xml.XmlPullParser;
 import org.jivesoftware.smack.xml.XmlPullParserException;
@@ -83,9 +82,7 @@ public class DeliveryReceiptRequest implements ExtensionElement {
      * @return the Message ID which will be used as receipt ID
      */
     public static String addTo(Message message) {
-        if (message.getStanzaId() == null) {
-            message.setStanzaId(StanzaIdUtil.newStanzaId());
-        }
+        message.ensureStanzaIdSet();
         message.addExtension(new DeliveryReceiptRequest());
         return message.getStanzaId();
     }

smack-extensions/src/main/java/org/jivesoftware/smackx/vcardtemp/VCardManager.java

@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2014 Florian Schmaus
+ * Copyright 2014-2019 Florian Schmaus
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -27,7 +27,6 @@ import org.jivesoftware.smack.XMPPConnection;
 import org.jivesoftware.smack.XMPPConnectionRegistry;
 import org.jivesoftware.smack.XMPPException.XMPPErrorException;
 import org.jivesoftware.smack.packet.IQ;
-import org.jivesoftware.smack.packet.id.StanzaIdUtil;
 
 import org.jivesoftware.smackx.disco.ServiceDiscoveryManager;
 import org.jivesoftware.smackx.vcardtemp.packet.VCard;
@@ -105,7 +104,7 @@ public final class VCardManager extends Manager {
         vcard.setType(IQ.Type.set);
         // Also make sure to generate a new stanza id (the given vcard could be a vcard result), in which case we don't
         // want to use the same stanza id again (although it wouldn't break if we did)
-        vcard.setStanzaId(StanzaIdUtil.newStanzaId());
+        vcard.setNewStanzaId();
         connection().createStanzaCollectorAndSend(vcard).nextResultOrThrow();
     }
 

smack-integration-test/src/main/java/org/jivesoftware/smackx/mam/MamIntegrationTest.java

@@ -67,7 +67,7 @@ public class MamIntegrationTest extends AbstractSmackIntegrationTest {
         EntityBareJid userTwo = conTwo.getUser().asEntityBareJid();
 
         Message message = new Message(userTwo);
-        String messageId = message.setStanzaId();
+        String messageId = message.ensureStanzaIdSet();
         final String messageBody = "Test MAM message (" + testRunId + ')';
         message.setBody(messageBody);