How to check if a string contains a date in Java?

Question

How do I check if a string contains a date of this form:

Sunday, January 15, 2012 at 7:36pm EST

The data I\'m working with contains

Answer 1

You could first check the presence of your date with a regex:

\w+,\s+\w+\s+\d+\,\s+\d+\s+at\s+\d+:\d+(pm|am)\s+\w{3,4}

This regex matches both

Rahul Chowdhury Sunday, January 15, 2012 at 7:37pm EST
Aritra Sinha Nirmal Friday, April 1, 2016 at 10:16pm EDT

https://regex101.com/r/V0dAf8/2/

When you found the match in your text then you could use SimpleDateFormat to check if it is well formed.

String input = "Rahul Chowdhury Sunday, January 15, 2012 at 7:37pm EST";
String regex = "(\\w+,\\s+\\w+\\s+\\d+\\,\\s+\\d+\\s+at\\s+\\d+:\\d+(pm|am)\\s+\\w{3,4})";
Matcher matcher = Pattern.compile(regex).matcher(input);
if (matcher.find()) {
  System.out.println(matcher.group(1));
}

This will print:

Sunday, January 15, 2012 at 7:37pm EST