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Why didn't you consider Google Protocol Buffers or Apache Avro? Why would you bother benchmarking Java native serialization, when it's been deprecated? More on reddit.com

Back in the "old days" of application servers Sun touted how you could have multiple machines connected together for the whole application. For example, three machines, web front end, database, and business logic. Java objects that were transferred between the machines needed to be serialized. More on reddit.com

Object are unordered, arrays are ordered. You would have to change the structure to keep the order More on reddit.com