Prevent poorly-extended ParcelableSpans from writing to parcels

If a developer extends an existing ParcelableSpan and overwrites
writeToParcel, TextUtils will crash when attempting to unparcel
since the span type ID is not accurate. This CL makes a separate
framework-private method for writeToParcel to ensure that even if
a developer extends a ParcelableSpan class, they won't modify the
parceling or unparceling code that's tied to the span type ID.

Bug: 21274544
Change-Id: If4c3506a55999df7a3b6d87cb8d550235d7a02c6

1 files changed, 18 insertions, 1 deletions

diff --git a/core/java/android/text/ParcelableSpan.java b/core/java/android/text/ParcelableSpan.java
index 224511a..d7c1a4b 100644
--- a/core/java/android/text/ParcelableSpan.java
+++ b/core/java/android/text/ParcelableSpan.java
@@ -16,6 +16,7 @@
 
 package android.text;
 
+import android.os.Parcel;
 import android.os.Parcelable;
 
 /**
@@ -27,5 +28,21 @@ public interface ParcelableSpan extends Parcelable {
     /**
      * Return a special type identifier for this span class.
      */
-    public abstract int getSpanTypeId();
+    int getSpanTypeId();
+
+    /**
+     * Internal implementation of {@link #getSpanTypeId()} that is not meant to
+     * be overridden outside of the framework.
+     *
+     * @hide
+     */
+    int getSpanTypeIdInternal();
+
+    /**
+     * Internal implementation of {@link Parcelable#writeToParcel(Parcel, int)}
+     * that is not meant to be overridden outside of the framework.
+     *
+     * @hide
+     */
+    void writeToParcelInternal(Parcel dest, int flags);
 }