Regex to match file extension

Question

I have file names separated by colon :

This one is working as expected

String fileName = "test.pdf:test1.txt:test2.png:test3.jpg:test4.jpeg:test5.doc";
String ext = "pdf";
System.out.println(fileName.matches(".*\\b\\."+ext+":\\b.*"));

but when a matching file is at the end, above solution does not work

String fileName = "test1.txt:test2.png:test3.jpg:test4.jpeg:test5.doc:test.pdf";

What is the regex to achieve it?

Answer 1

Change the pattern to look for : or the end $ :

".*\\." + ext + "(:|$).*"

(Also, I removed the unnecessary \\\\b .)

Answer 2

You can use pattern and matcher.

Pattern pdfPattern = Pattern.compile("\\.pdf");
if(pdfPattern.matcher(fileName).find()){
    System.out.println("Found PDF");
}