ISODateFormat.java

package liquibase.util;

import java.sql.Time;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

public class ISODateFormat {

    private SimpleDateFormat dateTimeFormat = new SimpleDateFormat(DATE_TIME_FORMAT_STRING);
    private SimpleDateFormat dateTimeFormatWithSpace = new SimpleDateFormat(DATE_TIME_FORMAT_STRING_WITH_SPACE);
    private SimpleDateFormat timeFormat = new SimpleDateFormat("HH:mm:ss");
    private SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
    private static final String DATE_TIME_FORMAT_STRING = "yyyy-MM-dd'T'HH:mm:ss";
    private static final String DATE_TIME_FORMAT_STRING_WITH_SPACE = "yyyy-MM-dd HH:mm:ss";


    public String format(java.sql.Date date) {
        return dateFormat.format(date);
    }

    public String format(java.sql.Time date) {
        return timeFormat.format(date);
    }

    public String format(java.sql.Timestamp date) {
        StringBuilder sb = new StringBuilder(dateTimeFormat.format(date));
        int nanos = date.getNanos();
        if (nanos != 0) {
            String nanosString = String.format("%09d", nanos);
            int lastNotNullIndex = 8;
            for (; lastNotNullIndex > 0; lastNotNullIndex--) {
                if (nanosString.charAt(lastNotNullIndex) != '0') {
                    break;
                }
            }
            sb.append('.');
            sb.append(nanosString.substring(0, lastNotNullIndex + 1));
        }
        return sb.toString();
    }

    public String format(Date date) {
        if (date == null) {
            return null;
        }
        if (date instanceof java.sql.Date) {
            return format(((java.sql.Date) date));
        } else if (date instanceof Time) {
            return format(((java.sql.Time) date));
        } else if (date instanceof java.sql.Timestamp) {
            return format(((java.sql.Timestamp) date));
        } else {
            throw new RuntimeException("Unknown type: "+date.getClass().getName());
        }
    }

    public Date parse(String dateAsString) throws ParseException {
        int length = dateAsString.length();
        switch (length) {
        case 8:
            return new java.sql.Time(timeFormat.parse(dateAsString).getTime());
        case 10:
            return new java.sql.Date(dateFormat.parse(dateAsString).getTime());
        case 19:
            if (dateAsString.contains(" ")) {
                return new java.sql.Timestamp(dateTimeFormatWithSpace.parse(dateAsString).getTime());
            } else {
                return new java.sql.Timestamp(dateTimeFormat.parse(dateAsString).getTime());
            }
        default:
            if (length < 19 || dateAsString.charAt(19) != '.') {
                throw new ParseException(String.format("Unknown date format to parse: %s.", dateAsString), 0);
            }
            long time = 0;
            if (dateAsString.contains(" ")) {
                time = dateTimeFormatWithSpace.parse(dateAsString.substring(0, 19)).getTime();
            } else {
                time = dateTimeFormat.parse(dateAsString.substring(0, 19)).getTime();
            }
            int nanos = Integer.parseInt(dateAsString.substring(20));
            for (; length < 29; length++) {
                nanos *= 10;
            }
            java.sql.Timestamp timestamp = new java.sql.Timestamp(time);
            timestamp.setNanos(nanos);
            return timestamp;
        }
    }
}