protected final <T extends Message> IoBufferEx encode(
String cacheKey,
MessageEncoder<T> encoder,
T message,
IoBufferAllocatorEx<?> allocator,
int flags) {
ConcurrentMap<String, IoBufferEx> cache = message.getCache();
// if cache is not initialized, throw exception (caller should guard)
if (cache == null) {
throw new IllegalStateException("Cache not initialized");
}
// lookup existing cached encoding entry
IoBufferEx cachedBuffer = cache.get(cacheKey);
if (cachedBuffer == null) {
// when cachedBuffer is null, perform encode, then cache the result
// with standard atomic race condition awareness (put-if-absent)
if ((flags & FLAG_ZERO_COPY) != 0) {
if (!cache.isEmpty()) {
flags &= ~FLAG_ZERO_COPY;
}
}
IoBufferEx newCachedBuffer = encoder.encode(allocator, message, flags);
if (newCachedBuffer instanceof MessageBuffer<?>) {
MessageBuffer<?> cacheableBuffer = (MessageBuffer<?>) newCachedBuffer;
cacheableBuffer.setAutoCache(true);
}
cachedBuffer = cache.putIfAbsent(cacheKey, newCachedBuffer);
if (cachedBuffer == null) {
cachedBuffer = newCachedBuffer;
}
}
return cachedBuffer;
}
