As an alternative to the existing serialization methods, Hazelcast offers a language/platform independent Portable serialization that has the following advantages:
- Supports multi-version of the same object type.
- Fetches individual fields without having to rely on reflection.
- Queries and indexing support without deserialization and/or reflection.
In order to support these features, a serialized Portable object contains meta information like the version and the concrete location of the each field in the binary data. This way, Hazelcast navigates in the byte[] and deserializes only the required field without actually deserializing the whole object. This improves the Query performance.
With multi-version support, you can have two cluster members where each has different versions of the same object. Hazelcast will store both meta information and use the correct one to serialize and deserialize Portable objects depending on the member. This is very helpful when you are doing a rolling upgrade without shutting down the cluster.
Portable serialization is totally language independent and is used as the binary protocol between Hazelcast server and clients.