Date date = new Date(114, 2, 18);

package com.balicanta.onlyfocus;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class SimpleDateFormatThreadUnsafetyExample {

    private static SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");

    public static void main(String[] args) {
        String dateStr = "2018-06-22T10:00:00";

        ExecutorService executorService = Executors.newFixedThreadPool(10);
        Runnable task = new Runnable() {
            @Override
            public void run() {
                parseDate(dateStr);
            }
        };

        for(int i = 0; i < 100; i++) {
            executorService.submit(task);
        }

        executorService.shutdown();
    }

    private static void parseDate(String dateStr) {
        try {
            Date date = simpleDateFormat.parse(dateStr);
            System.out.println("Successfully Parsed Date " + date);
        } catch (ParseException e) {
            System.out.println("ParseError " + e.getMessage());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

// 取得現在的日期
LocalDate localDate = LocalDate.now();

// 傳入數字，取得日期
LocalDate.of(2015, 02, 20);
 
// 透過字串轉換成日期
LocalDate.parse("2015-02-20");

// 現在日期加一天
LocalDate tomorrow = LocalDate.now().plusDays(1);

// 現在的日期減一個月
LocalDate previousMonthSameDay = LocalDate.now().minus(1, ChronoUnit.MONTHS);


// 取得今天是星期幾？
DayOfWeek sunday = LocalDate.parse("2016-06-12").getDayOfWeek();

// 取得今天是一個月的第幾天？
int twelve = LocalDate.parse("2016-06-12").getDayOfMonth();

// 是否為閏年
boolean leapYear = LocalDate.now().isLeapYear();

// 兩兩日期的比較
boolean notBefore = LocalDate.parse("2016-06-12").isBefore(LocalDate.parse("2016-06-11"));
 
boolean isAfter = LocalDate.parse("2016-06-12").isAfter(LocalDate.parse("2016-06-11"));

// 透過現在的 Local Date 取得一個 LocalDate Time 的時間
LocalDateTime beginningOfDay = LocalDate.parse("2016-06-12").atStartOfDay();

// 透過現在的日期，平移到這個月的第一天
LocalDate firstDayOfMonth = 
	LocalDate.parse("2016-06-12").with(TemporalAdjusters.firstDayOfMonth());

// 取得現在時間，只有時間，沒有日期
LocalTime now = LocalTime.now();

// 透過字串取得時間
LocalTime sixThirty = LocalTime.parse("06:30");

// 透過數字取得時間
LocalTime sixThirty = LocalTime.of(6, 30);

// 加一個小時
LocalTime sevenThirty = LocalTime.parse("06:30").plus(1, ChronoUnit.HOURS);

// 取得小時
int six = LocalTime.parse("06:30").getHour();

// 兩者時間的比較
boolean isbefore = LocalTime.parse("06:30").isBefore(LocalTime.parse("07:30"));

// 取得本地日期時間
LocalDateTime.now();

// 透過數字取得
LocalDateTime.of(2015, Month.FEBRUARY, 20, 06, 30);

// 透過文字取得
LocalDateTime.parse("2015-02-20T06:30:00");

// 日期、時間的運算
localDateTime.plusDays(1);

localDateTime.minusHours(2);

// 透過字串取得 ZoneId
ZoneId zoneId = ZoneId.of("Europe/Paris");

// 取得所有的 ZoneId
Set<String> allZoneIds = ZoneId.getAvailableZoneIds();

// 透過字串，轉換一個具有 Zone ID 的字串
ZonedDateTime.parse("2015-05-03T10:15:30+01:00[Europe/Paris]");

// 取得兩個日期
LocalDate initialDate = LocalDate.parse("2007-05-10");

LocalDate finalDate = initialDate.plus(Period.ofDays(5));


// 取得兩者的差距天數
int five = Period.between(initialDate, finalDate).getDays();

ocalTime initialTime = LocalTime.of(6, 30, 0);
 
LocalTime finalTime = initialTime.plus(Duration.ofSeconds(30));

long thirty = Duration.between(initialTime, finalTime).getSeconds();

LocalDateTime localDateTime = LocalDateTime.of(2015, Month.JANUARY, 25, 6, 30);

// 透過內建的 Formatter 完成
String localDateString = localDateTime.format(DateTimeFormatter.ISO_DATE);

localDateTime
  .format(DateTimeFormatter.ofLocalizedDateTime(FormatStyle.MEDIUM))
  .withLocale(Locale.UK);

DateTimeFormatter italianFormatter = new DateTimeFormatterBuilder()
        .appendText(ChronoField.DAY_OF_MONTH)
        .appendLiteral(". ")
        .appendText(ChronoField.MONTH_OF_YEAR)
        .appendLiteral(" ")
        .appendText(ChronoField.YEAR)
        .parseCaseInsensitive()
        .toFormatter(Locale.ITALIAN);