/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.*;
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		List<String> strs = Arrays.asList("doubleexsension.pdf.pdf","noextension","nameWithDot.","properName.pdf");
		for (String str : strs)
			System.out.println(str.replaceAll("(?:(\\.\\w+)\\1*|\\.|([^.]))$", "$2.pdf"));
 
	}
}

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