read/write file

[akl]

FileInputStream in=new FileInputStream(fileName);
FileOutputStream out=new FileOutputStream(fileName");
nByte=in.read();
while(nByte!=-1){
out.write(change(nByte));
nByte=in.read();
}

How to read and write in the same file?
Why this code doesn't work correctly ?

[ShadowWalker]

Take a look here Java 103 : File-handling under Java there are two good examples of read and Write to a file ..

[JosAH]

Why this code doesn't work correctly ?

It does work correctly; your assumptions how stuff works is incorrect; instead, you should've read the API documentation for the FileOutputStream class.

kind regards,

Jos

[akl]

I want read and write to file at a same time in same file.
Maybe solution is use temporary file.

[JosAH]

I want read and write to file at a same time in same file.
Maybe solution is use temporary file.

Yep, that's the way to go: read the (previous) data, do with it what you have to do and finally write back the upated (new) data to the file; possibly you don't even need a temporary file.

kind regards,

Jos

[akl]

Your suggesting. save previous data to data array, then write back data to the file?