第12章示例代码

Author: ipofss

src/main/java/com/wbs/java8lambda/chapter12/DateTimeExample.java

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+package com.wbs.java8lambda.chapter12;
+
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.time.*;
+import java.time.chrono.JapaneseDate;
+import java.time.format.DateTimeFormatter;
+import java.time.format.DateTimeFormatterBuilder;
+import java.time.temporal.*;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.Locale;
+
+/**
+ * TODO
+ *
+ * @author: wangbingshuai
+ * @create: 2019-11-12 16:54
+ **/
+public class DateTimeExample {
+
+    private static final ThreadLocal<DateFormat> formatters = new ThreadLocal<DateFormat>() {
+        @Override
+        protected DateFormat initialValue() {
+            return new SimpleDateFormat("dd-MMM-yyyy");
+        }
+    };
+
+    public static void main(String[] args) {
+//        useOldDate();
+//        useLocalDate();
+//        useTemporalAdjuster();
+        useDateFormatter();
+    }
+
+    private static void useOldDate() {
+        Date date = new Date(119, 10, 18);
+        System.out.println(date);
+
+        System.out.println(formatters.get().format(date));
+
+        Calendar instance = Calendar.getInstance();
+        instance.set(2019, Calendar.FEBRUARY, 18);
+        System.out.println(instance);
+    }
+
+    private static void useLocalDate() {
+        LocalDate date = LocalDate.of(2019, 11, 18);
+//        System.out.println(date.getYear());
+//        System.out.println(date.getMonth());
+//        System.out.println(date.getDayOfMonth());
+//        System.out.println(date.getDayOfWeek());
+//        System.out.println(date.lengthOfMonth());
+//        System.out.println(date.isLeapYear());
+        System.out.println(date);
+
+//        System.out.println(date.get(ChronoField.YEAR));
+//        System.out.println(date.get(ChronoField.MONTH_OF_YEAR));
+//        System.out.println(date.get(ChronoField.DAY_OF_MONTH));
+
+        LocalTime time = LocalTime.of(12, 34, 56);
+//        System.out.println(time.getHour());
+//        System.out.println(time.getMinute());
+//        System.out.println(time.getSecond());
+        System.out.println(time);
+
+        LocalDateTime dt1 = LocalDateTime.of(2019, Month.DECEMBER, 18, 12, 34, 56);
+//        System.out.println(LocalDateTime.of(date, time));
+//        System.out.println(date.atTime(12, 34, 56));
+//        System.out.println(date.atTime(time));
+//        System.out.println(time.atDate(date));
+        System.out.println(dt1);
+
+        LocalDate date1 = dt1.toLocalDate();
+        System.out.println(date1);
+        LocalTime time1 = dt1.toLocalTime();
+        System.out.println(time1);
+
+        Instant instant = Instant.ofEpochSecond(60 * 60 * 24 * 365 * 44);
+        Instant now = Instant.now();
+
+        Duration d1 = Duration.between(LocalTime.of(12, 34, 21), time);
+        Duration d2 = Duration.between(instant, now);
+        System.out.println(d1.getSeconds());
+        System.out.println(d2.getSeconds());
+
+        Duration threeMinutes = Duration.of(3, ChronoUnit.MINUTES);
+        System.out.println(threeMinutes);
+
+        JapaneseDate japaneseDate = JapaneseDate.from(date);
+        System.out.println(japaneseDate);
+    }
+
+    private static void useTemporalAdjuster() {
+        LocalDate date = LocalDate.of(2019, 11, 18);
+        date = date.with(TemporalAdjusters.nextOrSame(DayOfWeek.SUNDAY));
+        System.out.println(date);
+        date = date.with(TemporalAdjusters.lastDayOfMonth());
+        System.out.println(date);
+
+        date = date.with(new NextWorkingDay());
+        System.out.println(date);
+        date = date.with(TemporalAdjusters.nextOrSame(DayOfWeek.FRIDAY));
+        System.out.println(date);
+        date = date.with(new NextWorkingDay());
+        System.out.println(date);
+
+        date = date.with(TemporalAdjusters.nextOrSame(DayOfWeek.FRIDAY));
+        System.out.println(date);
+        date = date.with(temporal -> {
+            DayOfWeek dow = DayOfWeek.of(temporal.get(ChronoField.DAY_OF_WEEK));
+            int dayToAdd = 1;
+            if (dow == DayOfWeek.FRIDAY) {
+                dayToAdd = 3;
+            }
+            if (dow == DayOfWeek.SATURDAY) {
+                dayToAdd = 2;
+            }
+            return temporal.plus(dayToAdd, ChronoUnit.DAYS);
+        });
+        System.out.println(date);
+    }
+
+    private static class NextWorkingDay implements TemporalAdjuster {
+        @Override
+        public Temporal adjustInto(Temporal temporal) {
+            DayOfWeek dow = DayOfWeek.of(temporal.get(ChronoField.DAY_OF_WEEK));
+            int dayToAdd = 1;
+            if (dow == DayOfWeek.FRIDAY) {
+                dayToAdd = 3;
+            }
+            if (dow == DayOfWeek.SATURDAY) {
+                dayToAdd = 2;
+            }
+            return temporal.plus(dayToAdd, ChronoUnit.DAYS);
+        }
+    }
+
+    private static void useDateFormatter() {
+        LocalDate date = LocalDate.of(2019, 11, 18);
+        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy");
+        DateTimeFormatter chinaFormatter = DateTimeFormatter.ofPattern("d. MMMM yyyy", Locale.CHINESE);
+
+        System.out.println(date.format(DateTimeFormatter.ISO_LOCAL_DATE));
+        System.out.println(date.format(formatter));
+        System.out.println(date.format(chinaFormatter));
+
+        DateTimeFormatter complexFormatter = new DateTimeFormatterBuilder()
+                .appendText(ChronoField.DAY_OF_MONTH)
+                .appendLiteral(". ")
+                .appendText(ChronoField.MONTH_OF_YEAR)
+                .appendLiteral(" ")
+                .appendText(ChronoField.YEAR)
+                .parseCaseInsensitive()
+                .toFormatter(Locale.CHINESE);
+        System.out.println(date.format(complexFormatter));
+    }
+}