Fix Javadoc and null analysis related warnings

This CL also adds @SuppressWarning("unused" to java-overridable package.

Bug: 18003991
Change-Id: If70527e30654384705d7a814f5efd181d9f539e1

3 files changed, 5 insertions, 6 deletions

diff --git a/java/src/com/android/inputmethod/event/CombinerChain.java b/java/src/com/android/inputmethod/event/CombinerChain.java
index 2d2731f21..b5863ed2d 100644
--- a/java/src/com/android/inputmethod/event/CombinerChain.java
+++ b/java/src/com/android/inputmethod/event/CombinerChain.java
@@ -97,7 +97,8 @@ public class CombinerChain {
      *   new event. However it may never be null.
      */
     @Nonnull
-    public Event processEvent(final ArrayList<Event> previousEvents, final Event newEvent) {
+    public Event processEvent(final ArrayList<Event> previousEvents,
+            @Nonnull final Event newEvent) {
         final ArrayList<Event> modifiablePreviousEvents = new ArrayList<>(previousEvents);
         Event event = newEvent;
         for (final Combiner combiner : mCombiners) {
diff --git a/java/src/com/android/inputmethod/event/DeadKeyCombiner.java b/java/src/com/android/inputmethod/event/DeadKeyCombiner.java
index 2e65a08fa..9d7cc0561 100644
--- a/java/src/com/android/inputmethod/event/DeadKeyCombiner.java
+++ b/java/src/com/android/inputmethod/event/DeadKeyCombiner.java
@@ -217,11 +217,8 @@ public class DeadKeyCombiner implements Combiner {
 
     @Nonnull
     private static Event createEventChainFromSequence(final @Nonnull CharSequence text,
-            final Event originalEvent) {
-        if (text.length() <= 0) {
-            return originalEvent;
-        }
-        Event lastEvent = null;
+            @Nonnull final Event originalEvent) {
+        Event lastEvent = originalEvent;
         int codePoint = 0;
         for (int i = text.length(); i > 0; i -= Character.charCount(codePoint)) {
             codePoint = Character.codePointBefore(text, i);
diff --git a/java/src/com/android/inputmethod/event/Event.java b/java/src/com/android/inputmethod/event/Event.java
index 3e3ff771c..0e6d733cd 100644
--- a/java/src/com/android/inputmethod/event/Event.java
+++ b/java/src/com/android/inputmethod/event/Event.java
@@ -223,6 +223,7 @@ public class Event {
      * Creates an input event representing the manual pick of a punctuation suggestion.
      * @return an event for this suggestion pick.
      */
+    @Nonnull
     public static Event createPunctuationSuggestionPickedEvent(
             final SuggestedWordInfo suggestedWordInfo) {
         final int primaryCode = suggestedWordInfo.mWord.charAt(0);