From 4b8f7ca6b632fd3475c577d1322e7a426a97c4ea Mon Sep 17 00:00:00 2001
From: Florian Schmaus <flo@geekplace.eu>
Date: Wed, 9 May 2018 16:47:28 +0200
Subject: [PATCH] Make <body/> (XML) language optional

---
 .../jivesoftware/smack/packet/Message.java    | 28 ++++++++++---------
 .../smack/provider/BodyElementProvider.java   |  5 +---
 2 files changed, 16 insertions(+), 17 deletions(-)

diff --git a/smack-core/src/main/java/org/jivesoftware/smack/packet/Message.java b/smack-core/src/main/java/org/jivesoftware/smack/packet/Message.java
index fcd6b0d72..7a3ac84a9 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/packet/Message.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/packet/Message.java
@@ -315,8 +315,8 @@ public final class Message extends Stanza implements TypedCloneable<Message> {
 
     private Body getMessageBody(String language) {
         language = determineLanguage(language);
-        for (Body body : bodies) {
-            if (language.equals(body.language)) {
+        for (Body body : getBodies()) {
+            if (Objects.equals(language, body.language) || (language != null && language.equals(this.language) && body.language == null)) {
                 return body;
             }
         }
@@ -388,9 +388,11 @@ public final class Message extends Stanza implements TypedCloneable<Message> {
      */
     public boolean removeBody(String language) {
         language = determineLanguage(language);
-        for (Body body : bodies) {
-            if (language.equals(body.language)) {
-                return bodies.remove(body);
+        for (Body body : getBodies()) {
+            String bodyLanguage = body.getLanguage();
+            if (Objects.equals(bodyLanguage, language)) {
+                removeExtension(body);
+                return true;
             }
         }
         return false;
@@ -650,9 +652,6 @@ public final class Message extends Stanza implements TypedCloneable<Message> {
         }
 
         public Body(String language, String message, BodyElementNamespace namespace) {
-            if (language == null) {
-                throw new NullPointerException("Language cannot be null.");
-            }
             if (message == null) {
                 throw new NullPointerException("Message cannot be null.");
             }
@@ -662,9 +661,10 @@ public final class Message extends Stanza implements TypedCloneable<Message> {
         }
 
         /**
-         * Returns the language of this message body.
+         * Returns the language of this message body or {@code null} if the body extension element does not explicitly
+         * set a language, but instead inherits it from the outer element (usually a {@link Message} stanza).
          *
-         * @return the language of this message body.
+         * @return the language of this message body or {@code null}.
          */
         public String getLanguage() {
             return language;
@@ -683,7 +683,9 @@ public final class Message extends Stanza implements TypedCloneable<Message> {
         public int hashCode() {
             final int prime = 31;
             int result = 1;
-            result = prime * result + this.language.hashCode();
+            if (language != null) {
+                result = prime * result + this.language.hashCode();
+            }
             result = prime * result + this.message.hashCode();
             return result;
         }
@@ -701,7 +703,7 @@ public final class Message extends Stanza implements TypedCloneable<Message> {
             }
             Body other = (Body) obj;
             // simplified comparison because language and message are always set
-            return this.language.equals(other.language) && this.message.equals(other.message);
+            return Objects.equals(this.language, other.language) && this.message.equals(other.message);
         }
 
         @Override
@@ -717,7 +719,7 @@ public final class Message extends Stanza implements TypedCloneable<Message> {
         @Override
         public XmlStringBuilder toXML(String enclosingNamespace) {
             XmlStringBuilder xml = new XmlStringBuilder(this, enclosingNamespace);
-            xml.xmllangAttribute(getLanguage()).rightAngleBracket();
+            xml.optXmlLangAttribute(getLanguage()).rightAngleBracket();
             xml.escape(message);
             xml.closeElement(getElementName());
             return xml;
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/provider/BodyElementProvider.java b/smack-core/src/main/java/org/jivesoftware/smack/provider/BodyElementProvider.java
index 53fd25c20..5ace1e8f5 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/provider/BodyElementProvider.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/provider/BodyElementProvider.java
@@ -28,11 +28,8 @@ public class BodyElementProvider extends ExtensionElementProvider<Message.Body>
     @Override
     public Message.Body parse(XmlPullParser parser, int initialDepth) throws Exception {
         String xmlLang = ParserUtils.getXmlLang(parser);
-        if (xmlLang == null) {
-            xmlLang = "en";
-        }
-
         String body = parseElementText(parser);
+
         return new Message.Body(xmlLang, body);
     }
 }