Determining MIME Type of the File

This is used to determine the MIME type of the file

try {
//Type is used to find the type of the file. It can be "text/plain", "text/xml" ,etc
    String type = Files.probeContentType(filename);
    if (type == null) {
        System.err.format("'%s' has an" + " unknown filetype.%n", filename);
    } else if (!type.equals("text/plain") {
        System.err.format("'%s' is not" + " a plain text file.%n", filename);
        continue;
    }
} catch (IOException x) {
    System.err.println(x);
}