groovy/java regex check if “yyyy.MM.dd” format

问题

I have a string representing a date, for example "2010.12.25". How can I control if it is of "yyyy.MM.dd" format? There is no need to check the validness of the date.

回答1:

You have the Regex, in Groovy, you can just do:

boolean match = "2010.12.12" ==~ /\d{4}\.\d{2}\.\d{2}/

回答2:

use SimpleDateFormat to parse() the string, handling the exception to decide if it is a valid date string. don't use regex to check a date. e.g.:

2010.30.40
2010.13.34

回答3:

try {
    Date.parse('yyyy.MM.dd', '2013.12.21')
} catch(java.text.ParseException p) {
    println "Unparseable Date"
}

You can also use Groovy Date parsing to check the accuracy of date format.

回答4:

You can check the format of the date by using a SimpleDateFormat like this, because using regex for validating date formats is a very bad practice, IMHO.

String strDate = "2010.12.25";
DateFormat df = new SimpleDateFormat("yyyy.MM.dd");
try {
    Date date = df.parse(strDate);
    // If it comes here, then its a valid format
} catch (ParseException pe) {
    // If it comes here, then its not a valid date of this format.
}

回答5:

Try to this check this with method isValid(String dateStr),

 boolean isValid(String dateStr) {
     Matcher matcher=
        Pattern.compile("\\d{4}\\.\\d{2}\\.\\d{2}").matcher(dateStr);
    return matcher.matches();
  }

回答6:

Try this one

 String a = "2010.12.12";

            System.out.println(a.matches("\\d{4}\\.\\d{2}\\.\\d{2}"));

Output will be true

来源：https://stackoverflow.com/questions/20143208/groovy-java-regex-check-if-yyyy-mm-dd-format

标签

java

regex

date

groovy