Serialization question

[The_Nick]

What's the difference between ObjectOutputStream.writeUTF() and ObjectOutputStream.writeBytes()

Why would I choose one rather than the other?
I have read the API of each topic however I am still quite confused about it:
1) writeBytes() write 1 byte for each character non considering the higher bit.. ok
2) writeUTF() use UTF-8 encoding which uses 8 bits.. so it's not like this method uses UTF-16 and can encode more unicodes.. It still read 8 bits..
Furthermore writeBytes is to be used if the lenght of the String is not important. What does that mean? Real life example?
Furthermore, quoting the javadoc:

char: The char data type is a single 16-bit Unicode character. It has a minimum value of '\u0000' (or 0) and a maximum value of '\uffff' (or 65,535 inclusive).

...
I would be glad if anybody could provide me with a clarification.
Thanks a lot in advance.

The_Nick.

[admin]

The difference is in the bytes that are written to the stream. When you write a character to a stream as a byte, you write the actual byte representation of that character (i.e. 97 for a and so on), but when you write a character as UTF, it will be encoded in the UTF format which may or may not be same as the byte. So when you read a character written as UTF back as a byte it may not be same as the byte representation of that character.

HTH,
Paul.

[The_Nick]

But why do both methods work out only 8 bits of the 16 available in a char?
What if I am writing a char which takes advantage of the whole available bytes(2)?

Thanks in advance.

[admin]

Where did you see that OOS.writeUTF works on only 8 bits of a character?

[admin]

Check this out: http://docs.oracle.com/javase/7/docs/ap ... fied-utf-8
and http://en.wikipedia.org/wiki/UTF-8

[The_Nick]

Check this out: http://docs.oracle.com/javase/7/docs/ap ... fied-utf-8
and http://en.wikipedia.org/wiki/UTF-8

Very cool indeed, so sometimes it takes also 3 bytes..
The last question:
Why is writeBytes() usable only if the lenght of the string i not important?

Thanks in advance.

The_Nick.

[admin]

The last question:
Why is writeBytes() usable only if the lenght of the string i not important?

Thanks in advance.

The_Nick.

I am not sure what that means. What context was that statement was made in?

[The_Nick]

Basically the writeBytes does not store the lenght of the String.
However writeUTF does.

I have gathered it reading this http://stackoverflow.com/questions/1799 ... tfstring-s thread.

Why writeUTF stores the lenght of the String?

Thanks in advance.

The_Nick.