#Java# 文章列表 Java 安装 Java:第一个程序 Hello World Java:建议使用 UTF-8 编写 Java 代码 Java:package 包命名规范 使用 Intellij IDEA 创建 Java 项目 Java 布尔类型 Java 处理日期和时间 Java 正则表达式 Java finalize 方法 Java:空值 null Java 如何触发垃圾回收 Java ThreadLocal Java InheritableThreadLocal Java Integer之间的比较 Java 动态代理 Java 匿名类 Java 枚举 Java 如何静态导入 import static println Java 引用级别:强引用、软引用、弱引用、幽灵引用 Java try finally return 解惑 Java WeakHashMap Java ReferenceQueue 怎么写 Java 示例代码? Java 匿名类双大括号初始化 什么是 Java Bean Java 多行字符串 Java 快速生成 List Java 快速生成 Map Java 将异常堆栈转换为 String JDK SPI 的使用和源码分析 Java Map 中的 key 和 value 能否为 null ? Java List 和 数组的互相转换 Java 获取环境变量 Java 获取和设置系统属性 Java:如何获取当前进程的 PID ? Java 字符串左侧 右侧补充空格或者其他字符 Java 线程 Java:如何获取文本文件内容 Java:读取资源文件内容 Java:使用 JavaFx 构建 GUI Java:Class 类 Java:使用 instanceof 判断对象类型 一个自定义的 Java 工具类 Java:获取当前函数所属类的类名 Java:获取当前执行的函数名 Java:使用 String 的 split 函数拆分字符串 Java:获取字符的 Unicode 编号(代码点) Java:获取当前工作目录 Java:使用 Class 对象的 isArray 方法判断对象是否为数组 使用 Java 生成 CSV 文件 Java Mockito 测试框架快速入门 JUnit 入门 JUnit 单测隔离 Java JOOR 反射库 Java alibaba transmittable-thread-local 库:让 ThreadLocal 跨线程传播 Java 日志组件 slf4j 的使用和源码分析 Java Lombok 库:为你减少样板代码 Java:使用 cglib 实现动态代理 Java Hibernate validator 校验框架 Java 使用 Hessian2 序列化和反序列化 H2 数据库快速入门 Java:使用 Gson 库处理 JSON 数据 Java 集成 groovy 构建规则引擎 Java 13:安装 Java 13 新特性:文本块(多行字符串) 卸载 MacOS 上安装的 Java Java:执行 sql 文件 Java JDK 有哪些发行版 ? java拾遗:String和数组 java拾遗:由反转数组想到System.out的实现机制 java拾遗:如何读取properties文件内容 Java并发概念汇总 java拾遗:System.out.println()是什么? java拾遗:通过示例理解位运算 使用“庖丁解牛”进行中文分词 DBUtils简明教程 试用velocity模板引擎 Java:将字符串哈希为数字 kafka SnappyError no native library is found 问题

Java 处理日期和时间


#Java#


时间戳

long currentTimeMillis = System.currentTimeMillis();  // 毫秒级时间戳
long currentTimestamp = System.currentTimeMillis()/1000;  // 秒级时间戳

从 Java 8 开始加入的 Instant 类也可以获取秒级时间戳:

import java.time.Instant;

public class Main {

    public static void main(String[] args) {
        long currentTimestamp1 = System.currentTimeMillis()/1000;  // 秒级时间戳
        long currentTimestamp2 = Instant.now().getEpochSecond();   // 这个也是秒级时间戳

        System.out.println("当前秒级时间戳:" + currentTimestamp1);
        System.out.println("当前秒级时间戳:" + currentTimestamp2);
    }
}

java.time.LocalDateTime

LocalDatetime 类从 Java 8 开始引入。

该类的一个显著特点是,月从1开始,而不是从0开始,年也不用像 java.util.Date 那样加一个 1900。

获取当前日期和时间

import java.time.LocalDateTime;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime = LocalDateTime.now();
        System.out.println(localDateTime);
    }
}

运行结果示例:

2019-06-22T21:50:20.760

分表获取当前年月日时分秒

import java.time.LocalDateTime;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime = LocalDateTime.now();
        System.out.printf("%s-%s-%s %s:%s:%s\n",
                localDateTime.getYear(), localDateTime.getMonth().getValue(), localDateTime.getDayOfMonth(),
                localDateTime.getHour(), localDateTime.getMinute(), localDateTime.getSecond());
    }
    
}

运行结果示例:

2019-6-22 21:51:46

将秒级时间戳转换为 LocalDateTime

import java.time.Instant;
import java.time.LocalDateTime;
import java.time.ZoneId;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime = LocalDateTime.ofInstant(Instant.ofEpochSecond(1561211629L), ZoneId.systemDefault());
        System.out.printf("%s-%s-%s %s:%s:%s\n",
                localDateTime.getYear(), localDateTime.getMonth().getValue(), localDateTime.getDayOfMonth(),
                localDateTime.getHour(), localDateTime.getMinute(), localDateTime.getSecond());
    }

}

将 LocalDateTime 转换成时间戳

import java.time.Instant;
import java.time.LocalDateTime;
import java.time.ZoneId;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime = LocalDateTime.of(2019, 6, 23, 9, 0);
        System.out.println(localDateTime);
        Instant instant = localDateTime.atZone(ZoneId.systemDefault()).toInstant();
        System.out.println(instant.getEpochSecond());  // 秒级时间戳
        System.out.println(instant.toEpochMilli());    // 毫秒级时间戳
    }

}

运行结果示例:

2019-06-23T09:00
1561251600
1561251600000

也可以像下面这样获取秒级时间戳:

import java.time.LocalDateTime;
import java.time.ZoneId;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime = LocalDateTime.of(2019, 6, 23, 9, 0);
        System.out.println( localDateTime.atZone(ZoneId.systemDefault()).toEpochSecond() );;
    }

}

格式化 LocalDateTime

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.time.format.FormatStyle;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime = LocalDateTime.now();
        System.out.println( localDateTime.format(DateTimeFormatter.ISO_DATE) );
        System.out.println( localDateTime.format(DateTimeFormatter.ofLocalizedDate(FormatStyle.FULL)) );
        System.out.println( localDateTime.format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")) );
    }

}

运行结果示例:

2019-06-22
2019年6月22日 星期六
2019-06-22 22:02:38

字符串转换为 LocalDateTime

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;

public class Main {

    public static void main(String[] args) {
        DateTimeFormatter df = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
        LocalDateTime localDateTime = LocalDateTime.parse("2019-06-18 12:00:00", df);
        System.out.println( localDateTime );
    }

}

模式可以在 DateTimeFormatter 的源码注释中找到:

 *  Symbol  Meaning                     Presentation      Examples
 *  ------  -------                     ------------      -------
 *   G       era                         text              AD; Anno Domini; A
 *   u       year                        year              2004; 04
 *   y       year-of-era                 year              2004; 04
 *   D       day-of-year                 number            189
 *   M/L     month-of-year               number/text       7; 07; Jul; July; J
 *   d       day-of-month                number            10
 *
 *   Q/q     quarter-of-year             number/text       3; 03; Q3; 3rd quarter
 *   Y       week-based-year             year              1996; 96
 *   w       week-of-week-based-year     number            27
 *   W       week-of-month               number            4
 *   E       day-of-week                 text              Tue; Tuesday; T
 *   e/c     localized day-of-week       number/text       2; 02; Tue; Tuesday; T
 *   F       week-of-month               number            3
 *
 *   a       am-pm-of-day                text              PM
 *   h       clock-hour-of-am-pm (1-12)  number            12
 *   K       hour-of-am-pm (0-11)        number            0
 *   k       clock-hour-of-am-pm (1-24)  number            0
 *
 *   H       hour-of-day (0-23)          number            0
 *   m       minute-of-hour              number            30
 *   s       second-of-minute            number            55
 *   S       fraction-of-second          fraction          978
 *   A       milli-of-day                number            1234
 *   n       nano-of-second              number            987654321
 *   N       nano-of-day                 number            1234000000
 *
 *   V       time-zone ID                zone-id           America/Los_Angeles; Z; -08:30
 *   z       time-zone name              zone-name         Pacific Standard Time; PST
 *   O       localized zone-offset       offset-O          GMT+8; GMT+08:00; UTC-08:00;
 *   X       zone-offset 'Z' for zero    offset-X          Z; -08; -0830; -08:30; -083015; -08:30:15;
 *   x       zone-offset                 offset-x          +0000; -08; -0830; -08:30; -083015; -08:30:15;
 *   Z       zone-offset                 offset-Z          +0000; -0800; -08:00;
 *
 *   p       pad next                    pad modifier      1
 *
 *   '       escape for text             delimiter
 *   ''      single quote                literal           '
 *   [       optional section start
 *   ]       optional section end
 *   #       reserved for future use
 *   {       reserved for future use
 *   }       reserved for future use

获取某个时间对应的月份有多少天

import java.time.LocalDateTime;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime = LocalDateTime.now();
        System.out.println(localDateTime.toLocalDate().lengthOfMonth()); 
    }

}

toLocalDate 用于获取 LocalDate 对象。

lengthOfMonth 方法返回的是 int 类型。

运行结果示例:

30

获取一段时间前的时间

import java.time.LocalDateTime;
import java.time.temporal.ChronoUnit;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime1 = LocalDateTime.now();
        System.out.println(localDateTime1);
        LocalDateTime localDateTime2 = localDateTime1.minus(32, ChronoUnit.DAYS); // 32天前的时间
        System.out.println(localDateTime1); // localDateTime1 保持不变
        System.out.println(localDateTime2);
    }

}

运行结果示例:

2019-06-22T22:11:59.322
2019-06-22T22:11:59.322
2019-05-21T22:11:59.322

获取一段时间后的时间

import java.time.LocalDateTime;
import java.time.temporal.ChronoUnit;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime1 = LocalDateTime.now();
        System.out.println("localDateTime1: " + localDateTime1);
        LocalDateTime localDateTime2 = localDateTime1.plus(32, ChronoUnit.HOURS); // 32小时后的时间
        System.out.println("localDateTime1: " + localDateTime1); // localDateTime1 保持不变
        System.out.println("localDateTime2: " + localDateTime2);
    }

}

运行结果示例:

localDateTime1: 2019-06-23T08:48:14.321
localDateTime1: 2019-06-23T08:48:14.321
localDateTime2: 2019-06-24T16:48:14.321

指定时间

import java.time.LocalDateTime;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime1 = LocalDateTime.of(2019, 6, 23, 9, 0);
        System.out.println("localDateTime1: " + localDateTime1);
        LocalDateTime localDateTime2 = localDateTime1.withHour(20); // 将 hour 改成 20
        System.out.println("localDateTime1: " + localDateTime1);    // localDateTime1 保持不变
        System.out.println("localDateTime2: " + localDateTime2);
    }

}

运行结果示例:

localDateTime1: 2019-06-23T09:00
localDateTime1: 2019-06-23T09:00
localDateTime2: 2019-06-23T20:00

获取当天最早的时间、最晚的时间

import java.time.LocalDateTime;
import java.time.LocalTime;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime = LocalDateTime.of(2019, 6, 23, 9, 0);
        System.out.println(LocalDateTime.of(localDateTime.toLocalDate(), LocalTime.MIN)); // 当前最早的时间
        System.out.println(LocalDateTime.of(localDateTime.toLocalDate(), LocalTime.MAX)); // 当天最晚的时间
    }

}

运行结果示例:

2019-06-23T00:00
2019-06-23T23:59:59.999999999

LocalDateTime 转换为 Date

import java.time.LocalDateTime;
import java.time.ZoneId;
import java.util.Date;

public class Main {

    public static void main(String[] args) {
        LocalDateTime localDateTime = LocalDateTime.of(2019, 6, 23, 9, 0);
        Date date = Date.from(localDateTime.atZone(ZoneId.systemDefault()).toInstant());
        System.out.println(date);
        System.out.println(date.getTime());  // 毫秒级时间戳
    }

}

运行结果示例:

Sun Jun 23 09:00:00 CST 2019
1561251600000

判断两个 LocalDateTime 的时间先后关系

import java.time.LocalDateTime;

public class Main {

    public static void main(String[] args) {

        LocalDateTime localDateTime01 = LocalDateTime.of(2019, 6, 18, 12, 0);
        LocalDateTime localDateTime02 = LocalDateTime.of(2019, 6, 1, 12, 0);

        System.out.println( localDateTime01.isAfter(localDateTime02) );   // 类似的,还有 isBefore 等方法

    }

}

运行结果:

true

获取两个 LocalDateTime 之间的间隔

import java.time.Duration;
import java.time.LocalDateTime;
import java.time.temporal.ChronoUnit;

public class Main {

    public static void main(String[] args) {

        LocalDateTime localDateTime01 = LocalDateTime.of(2019, 6, 18, 12, 0);
        LocalDateTime localDateTime02 = LocalDateTime.of(2019, 6, 18, 13, 0);

        Duration duration = Duration.between(localDateTime01, localDateTime02);

        System.out.println( duration.get(ChronoUnit.SECONDS) );
        System.out.println( duration.getSeconds() );

    }

}

运行结果:

3600
3600

java.time.LocalDate

LocalDate 类从 Java 8 开始引入。相对于 LocalDateTime,LocalDate 仅处理年月日这三个维度。

获取当前年月日对应的 LocalDate

import java.time.LocalDate;

public class Main {

    public static void main(String[] args) {

        LocalDate localDate = LocalDate.now();
        
        System.out.println(localDate);
        System.out.printf("%s-%s-%s\n", localDate.getYear(), localDate.getMonthValue(), localDate.getDayOfMonth());
    }

}

运行结果示例:

2019-06-24
2019-6-24

生成指定时间的 LocalDate

import java.time.LocalDate;

public class Main {

    public static void main(String[] args) {

        LocalDate localDate = LocalDate.of(2019, 6, 18);

        System.out.println(localDate);
        System.out.printf("%s-%s-%s\n", localDate.getYear(), localDate.getMonthValue(), localDate.getDayOfMonth());
    }

}

运行结果:

2019-06-18
2019-6-18

获取指定时间是当年的第几天

import java.time.LocalDate;

public class Main {

    public static void main(String[] args) {
        LocalDate localDate = LocalDate.of(2019, 6, 18);
        System.out.println(localDate.getDayOfYear());
    }

}

运行结果:

169

将当年的第几天转换为 LocalDate

import java.time.LocalDate;

public class Main {

    public static void main(String[] args) {
        LocalDate localDate = LocalDate.ofYearDay(2019, 169);
        System.out.println(localDate);
    }

}

运行结果:

2019-06-18

计算两个 LocalDate 之间间隔的时间

import java.time.LocalDate;
import java.time.Period;
import java.time.temporal.ChronoUnit;

public class Main {

    public static void main(String[] args) {

        LocalDate localDate01 = LocalDate.of(2019, 6, 18);
        LocalDate localDate02 = LocalDate.of(2019, 6, 12);

        Period period = Period.between(localDate01, localDate02);

        System.out.println( period.get(ChronoUnit.DAYS) );

    }

}

运行结果:

-6

java.time.LocalTime

LocalTime 类从 Java 8 开始引入。相对于 LocalDateTime,LocalDate 仅处理时分秒这三个维度。秒,可以精确到纳秒。1秒等于10^9(10的9次方)纳秒。

获取当前时间对应的 LocalTime

import java.time.LocalTime;

public class Main {

    public static void main(String[] args) {
        LocalTime localTime = LocalTime.now();
        System.out.println( localTime );
        System.out.printf("%s:%s:%s %s\n", localTime.getHour(), localTime.getMinute(), localTime.getSecond(), localTime.getNano());
    }

}

运行结果示例:

23:42:15.555
23:42:15 555000000

生成指定时间的 LocalTime

import java.time.LocalTime;

public class Main {

    public static void main(String[] args) {
        LocalTime localTime = LocalTime.of(10, 25, 59);
        System.out.println( localTime );
    }

}

运行结果:

10:25:59

获取当前时间是当日的第几秒

import java.time.LocalTime;

public class Main {

    public static void main(String[] args) {
        LocalTime localTime = LocalTime.of(10, 25, 59);
        System.out.println(localTime.toSecondOfDay());
    }

}

运行结果:

37559

将当日的第几秒转换为 LocalTime

import java.time.LocalTime;

public class Main {

    public static void main(String[] args) {
        LocalTime localTime = LocalTime.ofSecondOfDay(37559);
        System.out.println(localTime);
    }

}

运行结果:

10:25:59

java.util.Date

获取当前时间

import java.util.Date;

public class Main {

    public static void main(String[] args) {
        Date date = new Date();     // 当前时间
        System.out.println("年: " + (1900+date.getYear()));  // 要加上 1900
        System.out.println("月: " + (1+date.getMonth()));    // 要加上 1
        System.out.println("日: " + date.getDate());
        System.out.println("时: " + date.getHours());
        System.out.println("分: " + date.getMinutes());
        System.out.println("秒: " + date.getSeconds());
    }

}

注意,上面用到的 get 开头的方法,已经被废弃了。

运行结果示例:

年: 2019
月: 6
日: 23
时: 10
分: 10
秒: 46

时间戳转换为 Date

import java.time.Instant;
import java.util.Date;

public class Main {

    public static void main(String[] args) {
        // 方法1
        Date date1 = new Date(1561256015L*1000); // 要使用毫秒级
        System.out.println(date1);

        // 方法2
        Date date2 = Date.from(Instant.ofEpochSecond(1561256015L));
        System.out.println(date2);
    }

}

运行结果示例:

Sun Jun 23 10:13:35 CST 2019
Sun Jun 23 10:13:35 CST 2019

Date 转换为时间戳

import java.util.Date;

public class Main {

    public static void main(String[] args) {
        Date date = new Date();
        System.out.println(date.toInstant().getEpochSecond());  // 返回 long 类型 
    }

}

运行结果示例:

1561256111

格式化 Date

import java.text.SimpleDateFormat;
import java.util.Date;

public class Main {

    public static void main(String[] args) {

        SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");

        Date date = new Date();

        System.out.println( df.format(date) );

    }

}

运行结果示例:

2019-06-24 06:53:56

注意,SimpleDateFormat 是线程不安全的,也就是不要在多线程中共享一个 SimpleDateFormat 实例。

字符串转换为 Date

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

public class Main {

    public static void main(String[] args) throws ParseException {

        SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

        Date date = df.parse("2019-06-18 12:00:00");

        System.out.println( date );
    }

}

运行结果:

Tue Jun 18 00:00:00 CST 2019

java.sql.Date

java.sql.Date 继承自 java.util.Date。不同的是,只支持年月日,不支持时分秒。

不支持时分秒

import java.sql.Date;

public class Main {

    public static void main(String[] args) {

        Date date = new Date(2019-1900, 6,18);
        System.out.println(date);
        System.out.println(date.getMinutes());  // 抛出异常

    }

}

运行时会抛出异常:

2019-07-18
Exception in thread "main" java.lang.IllegalArgumentException
	at java.sql.Date.getMinutes(Date.java:200)
	at Main.main(Main.java:9)

java.sql.Date 与时间戳互相转换

import java.sql.Date;

public class Main {

    public static void main(String[] args) {

        // 时间戳到 Date
        Date date = new Date(1561256015L*1000); // 毫秒级时间戳
        System.out.println(date);

        // Date 到时间戳
        System.out.println(date.getTime());

    }

}

运行结果:

2019-06-23
1561256015000

java.sql.Date 转换为 Instant、LocalDate

import java.sql.Date;
import java.time.Instant;
import java.time.LocalDate;

public class Main {

    public static void main(String[] args) {

        Date date = new Date(2019-1900, 6,18);
        Instant instant = date.toInstant();         // 转换为 Instant
        LocalDate localDate = date.toLocalDate();   // 转换为 LocalDate

    }

}

从字符串解析时间

import java.sql.Date;

public class Main {

    public static void main(String[] args) {

        Date date = Date.valueOf("2019-06-18");
        Date date2 = Date.valueOf("2019-6-18");
        System.out.println(date);
        System.out.println(date2);

    }

}

执行结果:

2019-06-18
2019-06-18

java.util.Calendar

查看 Calender 实例内容

import java.util.Calendar;

public class Main {

    public static void main(String[] args) {

        Calendar calendar = Calendar.getInstance();
        System.out.println(calendar);

    }

}

运行结果示例:

java.util.GregorianCalendar[time=1561343283169,areFieldsSet=true,areAllFieldsSet=true,lenient=true,zone=sun.util.calendar.ZoneInfo[id="Asia/Shanghai",offset=28800000,dstSavings=0,useDaylight=false,transitions=19,lastRule=null],firstDayOfWeek=1,minimalDaysInFirstWeek=1,ERA=1,YEAR=2019,MONTH=5,WEEK_OF_YEAR=26,WEEK_OF_MONTH=5,DAY_OF_MONTH=24,DAY_OF_YEAR=175,DAY_OF_WEEK=2,DAY_OF_WEEK_IN_MONTH=4,AM_PM=0,HOUR=10,HOUR_OF_DAY=10,MINUTE=28,SECOND=3,MILLISECOND=169,ZONE_OFFSET=28800000,DST_OFFSET=0]

MONTH 是从 0 开始算的,所以实际使用中要加1。周日是一周的第一天。

从 Calendar 中获取年月日时分秒

import java.util.Calendar;

public class Main {

    public static void main(String[] args) {

        Calendar calendar = Calendar.getInstance();

        System.out.printf("%s-%s-%s %s:%s:%s \n",
                calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH) + 1, calendar.get(Calendar.DAY_OF_MONTH),
                calendar.get(Calendar.HOUR_OF_DAY), calendar.get(Calendar.MINUTE), calendar.get(Calendar.SECOND)
        );

    }

}

运行结果示例:

2019-6-24 10:34:31 

Calendar 转换为时间戳

import java.util.Calendar;

public class Main {

    public static void main(String[] args) {

        Calendar calendar = Calendar.getInstance();
        calendar.set(2019, 6, 18, 18, 0, 0);

        // 转换为秒级时间戳
        System.out.println( calendar.toInstant().getEpochSecond() );

        // 转换为毫秒级时间戳
        System.out.println( calendar.getTimeInMillis() );

    }

}

运行结果:

1563444000
1563444000591

时间戳转换为 Calender

import java.util.Calendar;

public class Main {

    public static void main(String[] args) {

        Calendar calendar = Calendar.getInstance();

        calendar.setTimeInMillis(1563444000L*1000L);

        System.out.printf("%s-%s-%s %s:%s:%s \n",
                calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH) + 1, calendar.get(Calendar.DAY_OF_MONTH),
                calendar.get(Calendar.HOUR_OF_DAY), calendar.get(Calendar.MINUTE), calendar.get(Calendar.SECOND)
        );
        
    }

}

Calender 转换为 Date

import java.util.Calendar;
import java.util.Date;

public class Main {

    public static void main(String[] args) {

        Calendar calendar = Calendar.getInstance();

        Date date = calendar.getTime();

        System.out.println( date );

    }

}

运行结果示例:

Mon Jun 24 18:49:57 CST 2019

Date 转换为 Calender

import java.util.Calendar;
import java.util.Date;

public class Main {

    public static void main(String[] args) {

        Date date = new Date();
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);

        System.out.printf("%s-%s-%s %s:%s:%s \n",
                calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH)+1, calendar.get(Calendar.DAY_OF_MONTH),
                calendar.get(Calendar.HOUR_OF_DAY), calendar.get(Calendar.MINUTE), calendar.get(Calendar.SECOND)
        );

    }

}

( 本文完 )