Reading text file in ASCII or UTF-8 or UTF-16 or UTF-32?

Question

The following code will include the UTF-8 byte-order-mark (EF BB BF) in the first line from the source file:
BufferedReader reader = new BufferedReader(new FileReader(sourceFile));
String firstLine = reader.readLine();
This isn't desirable. I don't want to get the UTF-8 BOM in the text contents that I get from the IO API.
Now, I can do something like this:
InputStreamReader reader = new InputStreamReader(new FileInputStream(sourceFile), "UTF8");
However, that assumes that the program knows the encoding of the input file at design time. Unfortunately, my app takes files from the user who may supply files in UTF-8, UTF-16, ASCII, or some other text encoding. Doesn't Java have some sort of simple file reading API to auto-detect the specific text encoding, strip out any internal BOM type markings and return my a simple Java string of just the actual file contents?

Answer 1

MassimoH wrote:
However, that assumes that the program knows the encoding of the input file at design time.Well, the bottom line is that the program DOES have to know the encoding of the input file. Not necessarily at design time, but it does have to know it at run time. The BOMs are only the first problem you have encountered.
I believe there are algorithms used in browsers to guess at the encoding of HTML documents provided by bozos who don't specify an encoding, but I don't have any good information about them.