findbugs

Found reliance on default encoding

I am getting below bug from FindBugs,

Found reliance on default encoding in MyClass.print(String): String.getBytes()

Method

protected void print (String str) {
{
private OutputStream outStream = null;
.....
outStream.write(str.getBytes());
.......
}

What is the error, and how can this be resolved?

Solution

  • There are different ways of encoding a String as bytes -- the charset determines that encoding. If you don't specify a charset, as in your call to str.getBytes(), it uses the system default.

    FindBugs is warning you about this because you should think about what encoding you want to use for your output. If you're writing to a file, what are the readers of that file expecting? It is safest if you can specify an explicit encoding for the file so you don't write it one way and read it another way.

    To specify an explicit charset, use str.getBytes(Charset.forName("UTF-8")), for example. UTF-8 is a good choice because it is always supported and can encode any character.

    For example, .properties files are always ISO 8859-1 (i.e. Latin-1). That's documented so there is no ambiguity around what encoding to use.