We use java.util.regex.Pattern.compile(String regex) method which compiles the given regular expression into a pattern. Here regex is the expression to be compiled.
// Java program to check if given date is// valid or not.import java.util.regex.Matcher;import java.util.regex.Pattern; public class Lazyroar { // Returns true if d is in format // /dd/mm/yyyy public static boolean isValidDate(String d) { String regex = "^(1[0-2]|0[1-9])/(3[01]" + "|[12][0-9]|0[1-9])/[0-9]{4}$"; Pattern pattern = Pattern.compile(regex); Matcher matcher = pattern.matcher((CharSequence)d); return matcher.matches(); } public static void main(String args[]) { System.out.println(isValidDate("10/12/2016")); System.out.println(isValidDate("10/02/18")); }} |
Output:
true false
More ways to validate a date :
- SimpleDateFormat class. We can use parse method of this class to validate the date.
- Writing our own method to check if a date is valid.