import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.util.List;
import java.util.Locale;
 
public class Main {
    public static void main(String[] args) {
        List<String> list = List.of("Apr 1, 2019", "Aug 1, 2020", "Feb 20, 2018");
        DateTimeFormatter dtf = DateTimeFormatter.ofPattern("MMM d, uuuu", Locale.ENGLISH);
        list.forEach(s -> {
            LocalDate date = LocalDate.parse(s, dtf);
            System.out.printf("Default format: %s, Custom format: %s%n", date, date.format(dtf));
        });
    }
}

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