Don't reset cachedSize to 0 in getSerializedSize

This avoids a race-condition when cachedSize is momentarily set to 0
for non-empty messages if multiple threads call getSerializedSize
(e.g. during serialization).

This is a retry of https://android-review.googlesource.com/#/c/88570/.
getSerializedSize() has been kept non-final so that messages generated
with a previous version of the compiler will not break.

Change-Id: I8d8154a10938cde579ae19c55eae55b1e70e0bda

1 files changed, 1 insertions, 2 deletions

diff --git a/java/src/main/java/com/google/protobuf/nano/ExtendableMessageNano.java b/java/src/main/java/com/google/protobuf/nano/ExtendableMessageNano.java
index 839f21c..63c8afc 100644
--- a/java/src/main/java/com/google/protobuf/nano/ExtendableMessageNano.java
+++ b/java/src/main/java/com/google/protobuf/nano/ExtendableMessageNano.java
@@ -47,7 +47,7 @@ public abstract class ExtendableMessageNano<M extends ExtendableMessageNano<M>>
     protected List<UnknownFieldData> unknownFieldData;
 
     @Override
-    public int getSerializedSize() {
+    protected int computeSerializedSize() {
         int size = 0;
         int unknownFieldCount = unknownFieldData == null ? 0 : unknownFieldData.size();
         for (int i = 0; i < unknownFieldCount; i++) {
@@ -55,7 +55,6 @@ public abstract class ExtendableMessageNano<M extends ExtendableMessageNano<M>>
             size += CodedOutputByteBufferNano.computeRawVarint32Size(unknownField.tag);
             size += unknownField.bytes.length;
         }
-        cachedSize = size;
         return size;
     }