Use String.split() with multiple delimiters

I think you need to include the regex OR operator:

String[]tokens = pdfName.split("-|\\.");

What you have will match:
[DASH followed by DOT together] -.
not
[DASH or DOT any of them] - or .

Try this regex "[-.]+". The + after treats consecutive delimiter chars as one. Remove plus if you do not want this.

You can use the regex "\W".This matches any non-word character.The required line would be:

String[] tokens=pdfName.split("\\W");

Using Guava you could do this:

Iterable<String> tokens = Splitter.on(CharMatcher.anyOf("-.")).split(pdfName);

The string you give split is the string form of a regular expression, so:

private void getId(String pdfName){
    String[]tokens = pdfName.split("[\\-.]");
}

That means to split on any character in the [] (we have to escape - with a backslash because it's special inside []; and of course we have to escape the backslash because this is a string). (Conversely, . is normally special but isn't special inside [].)