import java.text.ParseException;
    import java.text.SimpleDateFormat;
    import java.time.Instant;
    import java.util.Date;
    import java.util.Locale;
    import java.util.TimeZone;

    public class Main {
        public static void main(String[] args) throws ParseException {
            String requestTime = "04:30 PM, Sat 5/12/2018";
            SimpleDateFormat sdf = new SimpleDateFormat("hh:mm a, EEE MM/dd/yyyy", Locale.ENGLISH);
            sdf.setTimeZone(TimeZone.getTimeZone("America/Toronto"));
            Date date = sdf.parse(requestTime);
            Instant reqInstant = date.toInstant();
            System.out.println(reqInstant);
        }
    }