diff --git a/smack-core/src/main/java/org/jivesoftware/smack/util/XmlStringBuilder.java b/smack-core/src/main/java/org/jivesoftware/smack/util/XmlStringBuilder.java
index c46e933c2..49972aacb 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/util/XmlStringBuilder.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/util/XmlStringBuilder.java
@@ -389,6 +389,22 @@ public class XmlStringBuilder implements Appendable, CharSequence, Element {
         return this;
     }
 
+    /**
+     * If the provided Integer argument is not null, then add a new XML attribute with the given name and the Integer as
+     * value.
+     *
+     * @param name the XML attribute name.
+     * @param value the optional integer to use as the attribute's value.
+     * @return a reference to this object.
+     * @since 4.4.1
+     */
+    public XmlStringBuilder optIntAttribute(String name, Integer value) {
+        if (value != null) {
+            attribute(name, value.toString());
+        }
+        return this;
+    }
+
     /**
      * Add the given attribute if value not null and {@code value => 0}.
      *
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/bob/element/BoBDataExtension.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/bob/element/BoBDataExtension.java
index 76414d9bc..7b7f81709 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/bob/element/BoBDataExtension.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/bob/element/BoBDataExtension.java
@@ -60,6 +60,26 @@ public class BoBDataExtension implements ExtensionElement {
         return NAMESPACE;
     }
 
+    /**
+     * Get the content ID.
+     *
+     * @return the content ID.
+     * @since 4.4.1
+     */
+    public final ContentId getContentId() {
+        return cid;
+    }
+
+    /**
+     * Get the Bits of Binary (BOB) data.
+     *
+     * @return the BoB data.
+     * @since 4.4.1
+     */
+    public final BoBData getBobData() {
+        return bobData;
+    }
+
     @Override
     public XmlStringBuilder toXML(org.jivesoftware.smack.packet.XmlEnvironment enclosingNamespace) {
         XmlStringBuilder xml = new XmlStringBuilder(this);
diff --git a/smack-im/src/main/java/org/jivesoftware/smack/roster/rosterstore/DirectoryRosterStore.java b/smack-im/src/main/java/org/jivesoftware/smack/roster/rosterstore/DirectoryRosterStore.java
index a78a44c28..3b8e70bb8 100644
--- a/smack-im/src/main/java/org/jivesoftware/smack/roster/rosterstore/DirectoryRosterStore.java
+++ b/smack-im/src/main/java/org/jivesoftware/smack/roster/rosterstore/DirectoryRosterStore.java
@@ -183,7 +183,7 @@ public final class DirectoryRosterStore implements RosterStore {
     private static Item readEntry(File file) {
         Reader reader;
         try {
-            // TODO: Should use Files.newBufferedReader() but it is not available on Android.
+            // TODO: Use Files.newBufferedReader() once Smack's minimum Android API level is 26 or higher.
             reader = new FileReader(file);
         } catch (FileNotFoundException e) {
             LOGGER.log(Level.FINE, "Roster entry file not found", e);
@@ -195,7 +195,7 @@ public final class DirectoryRosterStore implements RosterStore {
             Item item = RosterPacketProvider.parseItem(parser);
             reader.close();
             return item;
-        } catch (XmlPullParserException | IOException e) {
+        } catch (XmlPullParserException | IOException | IllegalArgumentException e) {
             boolean deleted = file.delete();
             String message = "Exception while parsing roster entry.";
             if (deleted) {