| RE: [hyades-dev] UTF-8 in HCE Data Exchange Format Proposal |
-----Original Message----- From: hoang.m.nguyen [mailto:hoang.m.nguyen@xxxxxxxxx] Sent: 31 August 2004 13:54 To: hyades-dev Subject: [hyades-dev] UTF-8 in HCE Data Exchange Format Proposal Hello all, We have discussed and came to the following proposal in our last HCE team meeting regarding to UTF-8 usage: If string data type is exchanged between the client and the HCE, it will be in the following format: - one byte indicates the size of the string length field: 2, 4 or 8 bytes - the actual length field (2, 4 or 8 bytes) - UTF-8 byte stream with no embedded null byte and no terminating null byte Here are some important points about this proposal: * This is only for string data type only. Other data types (int, float, double, etc.) are not affected. * No embedded null byte in the string. If this requires, multiple strings should be created instead. This should help C/C++ program to convert to its own string without additional checking. * No null byte at the end. If there is a length field in the beginning, it should not be forced to add one more the end (just for C program convenience). It will be very unnatural for Java programs to do so. The expectation is that most Java or C++ programs will probably convert it to String objects before manipulating anyway. * The first length indicator byte is really for optimal solution and scalability - most string lengths will be within 2-byte length size (my expectation is at 99%) - 4-byte length is also possible (e.g. Allans environmental variable) - 8-byte length is conceivable with the latest 64-bit memory addressing (as Frank de Jong pointed out) As always, all inputs and comments are welcome and appreciated. Regards,
Attachment:
Eclipse Test Performance Project - Overview for LinuxWorld 8-5-04.ppt
Description: MS-Powerpoint presentation