In org.msgpack:jackson-dataformat-msgpack:0.8.7 method MessagePacker::packString throw IllegalArgumentException("Unexpected UTF-8 encoder state") (line number 560).
In happens when string to encode less 2^16 and encoded string is greater then 2^16. In condition written >= (1 << 32) variable written has type int and condition 1 << 32 evaluates to 1 because 1 is long and there are type overflow.