Hi Gerd I started to think about this a while ago when I was fixing cities > 65535, and introduced some alternative names for get/getChar and put/putChar and also added some of the assertions. But then I noticed that some of the names I used were used for BIT I/O elsewhere, and also the Display tree shared the same code. I didn't like having code like: int n = reader.get() & 0xff; writer.putChar((char) val); inline; I think this is much clearer: int n = reader.getU1() writer.putU2(val) and allows for range checking, but you have to study the code to know if you should use putSx() or putUx() Maybe something like: getU1(), getU2(), getU3(), getUN(nBytes) getS1(), getS2(), getS3(), getSN(nBytes) putU1(int), putU2(int), putU3(int), putUN(nBytes, int) putS1(int), putS2(int), putS3(int), putSN(nBytes, int) For full integer/4 byte I/O, it is meaningless to differentiate between Signed & Unsigned, but might be clearer to have xxxU4() and xxxS4() routines as well and use instead of getInt()/putInt() There are names a bit like some of these already in imgfmt/app/ImgFile{Reader,Writer}.java and their implementations Regards Ticker On Thu, 2018-02-15 at 10:06 +0000, Gerd Petermann wrote:
Hi,
we have various methods to write an integer with 1, 2, 3, or 4 bytes to an img file. I always feel unsure what method to use because none of them makes clear what happens with negative values.
Besides that some of the existing routines seem to throw misleading exceptions, e.g. FileBackedImgFileWriter seems to assume that it is only used for the mdr tmp file and creates texts like this: throw new MapFailedException("could not write3 to mdr tmp file"); throw new MapFailedException("could not write put3 to mdr tmp file");
Only the javadoc for put1() and put2() tell me the range (0..255 or 0..65535) .
If I got that right put3() allows negative values, so I think it is NOT 0..16777215 but -8388608 .. 8388607 ?
I'd like to improve the readability of the code, but I don't want to mess up anything. Would it be possible to add comments to all the methods?
Gerd
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