Max size of a StringDocument

[thanodnl]

The UTF write function of java only accepts Strings less than 2^16-1 bytes. This could be unsuitable for future use.

Possibilities to go along with are:

• Accept it and live long and prosper
• use 4 bytes instead of 2 to store the length in bytes
• use vlq (variable length qualifier) to store the length

Both, the 4 bytes and vlq, solutions imply that the serialization and deserialization of Strings should be done manually. This is error prone work.

A solution should be in place before a stable version because it is hard to change the implementation later on while supporting data migration.