Add support for <text/> elements in SM's <failed/> element

Also introduce AbstractTextElement and StanzaErrorTextElement.

Fixes SMACK-760.

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

@@ -0,0 +1,56 @@
+/**
+ *
+ * Copyright © 2017 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.smack.packet;
+
+import org.jivesoftware.smack.util.StringUtils;
+import org.jivesoftware.smack.util.XmlStringBuilder;
+
+public abstract class AbstractTextElement implements ExtensionElement {
+
+    public static final String ELEMENT = "text";
+
+    private final String text;
+    private final String lang;
+
+    protected AbstractTextElement(String text, String lang) {
+        this.text = StringUtils.requireNotNullOrEmpty(text, "Text must not be null or empty");
+        this.lang = lang;
+    }
+
+    @Override
+    public String getElementName() {
+        return ELEMENT;
+    }
+
+    @Override
+    public XmlStringBuilder toXML() {
+        XmlStringBuilder xml = new XmlStringBuilder(this);
+        xml.optXmlLangAttribute(lang);
+        xml.rightAngleBracket();
+        xml.escape(text);
+        xml.closeElement(this);
+        return xml;
+    }
+
+    public final String getText() {
+        return text;
+    }
+
+    public final String getLang() {
+        return lang;
+    }
+}

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

@@ -0,0 +1,32 @@
+/**
+ *
+ * Copyright © 2017 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.smack.packet;
+
+public class StanzaErrorTextElement extends AbstractTextElement {
+
+    public static final String NAMESPACE = XMPPError.NAMESPACE;
+
+    public StanzaErrorTextElement(String text, String lang) {
+        super(text, lang);
+    }
+
+    @Override
+    public String getNamespace() {
+        return NAMESPACE;
+    }
+
+}

smack-tcp/src/main/java/org/jivesoftware/smack/sm/packet/StreamManagement.java

@@ -16,8 +16,12 @@
  */
 package org.jivesoftware.smack.sm.packet;
 
+import java.util.Collections;
+import java.util.List;
+
 import org.jivesoftware.smack.packet.ExtensionElement;
 import org.jivesoftware.smack.packet.Nonza;
+import org.jivesoftware.smack.packet.StanzaErrorTextElement;
 import org.jivesoftware.smack.packet.XMPPError;
 import org.jivesoftware.smack.util.XmlStringBuilder;
 
@@ -189,30 +193,46 @@ public class StreamManagement {
     public static class Failed implements Nonza {
         public static final String ELEMENT = "failed";
 
-        private XMPPError.Condition condition;
+        private final XMPPError.Condition condition;
+
+        private final List<StanzaErrorTextElement> textElements;
+
 
         public Failed() {
+            this(null, null);
         }
 
-        public Failed(XMPPError.Condition condition) {
+        public Failed(XMPPError.Condition condition, List<StanzaErrorTextElement> textElements) {
             this.condition = condition;
+            if (textElements == null) {
+                this.textElements = Collections.emptyList();
+            } else {
+                this.textElements = Collections.unmodifiableList(textElements);
+            }
         }
 
         public XMPPError.Condition getXMPPErrorCondition() {
             return condition;
         }
 
+        public List<StanzaErrorTextElement> getTextElements() {
+            return textElements;
+        }
+
         @Override
         public CharSequence toXML() {
             XmlStringBuilder xml = new XmlStringBuilder(this);
-            if (condition != null) {
-                xml.rightAngleBracket();
-                xml.append(condition.toString());
-                xml.xmlnsAttribute(XMPPError.NAMESPACE);
-                xml.closeElement(ELEMENT);
-            }
-            else {
+            if (condition == null && textElements.isEmpty()) {
                 xml.closeEmptyElement();
+            } else {
+                xml.rightAngleBracket();
+                if (condition != null) {
+                    // TODO This should use StanzaError (formerly XMPPError) in Smack 4.3 (see SMACK-769)
+                    xml.append(condition.toString());
+                    xml.xmlnsAttribute(XMPPError.NAMESPACE);
+                }
+                xml.append(textElements);
+                xml.closeElement(ELEMENT);
             }
             return xml;
         }

smack-tcp/src/main/java/org/jivesoftware/smack/sm/provider/ParseStreamManagement.java

@@ -17,7 +17,11 @@
 package org.jivesoftware.smack.sm.provider;
 
 import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
 
+import org.jivesoftware.smack.packet.AbstractTextElement;
+import org.jivesoftware.smack.packet.StanzaErrorTextElement;
 import org.jivesoftware.smack.packet.XMPPError;
 import org.jivesoftware.smack.sm.packet.StreamManagement.AckAnswer;
 import org.jivesoftware.smack.sm.packet.StreamManagement.AckRequest;
@@ -46,6 +50,7 @@ public class ParseStreamManagement {
         ParserUtils.assertAtStartTag(parser);
         String name;
         XMPPError.Condition condition = null;
+        List<StanzaErrorTextElement> textElements = new ArrayList<>(4);
         outerloop:
         while (true) {
             int event = parser.next();
@@ -54,7 +59,14 @@ public class ParseStreamManagement {
                 name = parser.getName();
                 String namespace = parser.getNamespace();
                 if (XMPPError.NAMESPACE.equals(namespace)) {
-                    condition = XMPPError.Condition.fromString(name);
+                    if (name.equals(AbstractTextElement.ELEMENT)) {
+                        String lang = ParserUtils.getXmlLang(parser);
+                        String text = parser.nextText();
+                        StanzaErrorTextElement stanzaErrorTextElement = new StanzaErrorTextElement(text, lang);
+                        textElements.add(stanzaErrorTextElement);
+                    } else {
+                        condition = XMPPError.Condition.fromString(name);
+                    }
                 }
                 break;
             case XmlPullParser.END_TAG:
@@ -66,7 +78,7 @@ public class ParseStreamManagement {
             }
         }
         ParserUtils.assertAtEndTag(parser);
-        return new Failed(condition);
+        return new Failed(condition, textElements);
     }
 
     public static Resumed resumed(XmlPullParser parser) throws XmlPullParserException, IOException {

smack-tcp/src/test/java/org/jivesoftware/smack/sm/provider/ParseStreamManagementTest.java

@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2014 Vyacheslav Blinov
+ * Copyright 2014 Vyacheslav Blinov, 2017 Florian Schmaus
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,8 +26,10 @@ import static org.junit.Assert.assertThat;
 import static org.junit.Assert.assertTrue;
 
 import java.io.IOException;
+import java.util.List;
 import java.util.Properties;
 
+import org.jivesoftware.smack.packet.StanzaErrorTextElement;
 import org.jivesoftware.smack.packet.XMPPError;
 import org.jivesoftware.smack.sm.packet.StreamManagement;
 import org.jivesoftware.smack.util.PacketParserUtils;
@@ -104,6 +106,30 @@ public class ParseStreamManagementTest {
         assertTrue(failedPacket.getXMPPErrorCondition() == errorCondition);
     }
 
+    @Test
+    public void testParseFailedWithTExt() throws XmlPullParserException, IOException {
+        // @formatter:off
+        final String failedNonza = "<failed h='20' xmlns='urn:xmpp:sm:3'>"
+                                   +  "<item-not-found xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'/>"
+                                   +  "<text xml:lang='en' xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'>"
+                                   +    "Previous session timed out"
+                                   +  "</text>"
+                                   + "</failed>";
+        // @formatter:on
+        XmlPullParser parser = PacketParserUtils.getParserFor(failedNonza);
+
+        StreamManagement.Failed failed = ParseStreamManagement.failed(parser);
+
+        assertEquals(XMPPError.Condition.item_not_found, failed.getXMPPErrorCondition());
+
+        List<StanzaErrorTextElement> textElements = failed.getTextElements();
+        assertEquals(1, textElements.size());
+
+        StanzaErrorTextElement textElement = textElements.get(0);
+        assertEquals("Previous session timed out", textElement.getText());
+        assertEquals("en", textElement.getLang());
+    }
+
     @Test
     public void testParseResumed() throws Exception {
         long handledPackets = 42;
@@ -139,7 +165,6 @@ public class ParseStreamManagementTest {
         assertThat(acknowledgementPacket.getHandledCount(), equalTo(handledPackets));
     }
 
-
     private static Properties initOutputProperties() {
         Properties properties = new Properties();
         properties.put(javax.xml.transform.OutputKeys.OMIT_XML_DECLARATION, "yes");