/* package whatever; // don't place package name! */
 
import java.util.regex.Matcher;
import java.util.regex.Pattern;
 
/* 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
	{
		String stringQualquer = "um teste qualquer12/02/1998 19/09/1880 Nulo";
 
		Pattern pattern = Pattern.compile("(\\d{2}/\\d{2}/\\d{4})");
 
		Matcher matcher = pattern.matcher(stringQualquer);
 
		if(matcher.find()) {
			System.out.println(matcher.group());
		}
	}
}

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