From 344212f5b6fe00e826ed1c2a2d29c7f188eab08d Mon Sep 17 00:00:00 2001
From: youzipi <blake_12@qq.com>
Date: Wed, 26 Jan 2022 18:36:15 +0800
Subject: [PATCH] feat(core:DateUtil): add `rangeFunc` and `rangeConsume`

---
 .../java/cn/hutool/core/date/DateUtil.java    | 58 ++++++++++++++++---
 .../java/cn/hutool/core/lang/RangeTest.java   | 26 +++++++++
 2 files changed, 77 insertions(+), 7 deletions(-)

diff --git a/hutool-core/src/main/java/cn/hutool/core/date/DateUtil.java b/hutool-core/src/main/java/cn/hutool/core/date/DateUtil.java
index c887ef349..268083716 100644
--- a/hutool-core/src/main/java/cn/hutool/core/date/DateUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/date/DateUtil.java
@@ -20,14 +20,10 @@ import java.time.LocalDateTime;
 import java.time.Year;
 import java.time.format.DateTimeFormatter;
 import java.time.temporal.TemporalAccessor;
-import java.util.Calendar;
-import java.util.Date;
-import java.util.GregorianCalendar;
-import java.util.LinkedHashSet;
-import java.util.List;
-import java.util.Locale;
-import java.util.TimeZone;
+import java.util.*;
 import java.util.concurrent.TimeUnit;
+import java.util.function.Consumer;
+import java.util.function.Function;
 
 /**
  * 时间工具类
@@ -1885,6 +1881,54 @@ public class DateUtil extends CalendarUtil {
 		return new DateRange(start, end, unit);
 	}
 
+	/**
+	 * 按日期范围遍历，执行 function
+	 *
+	 * @param start 起始日期时间（包括）
+	 * @param end   结束日期时间
+	 * @param unit  步进单位
+	 * @param func  每次遍历要执行的 function
+	 * @param <T>
+	 * @return
+	 */
+	public static <T> List<T> rangeFunc(Date start, Date end, final DateField unit, Function<Date, T> func) {
+		if (start == null || end == null || start.after(end)) {
+			return Collections.emptyList();
+		} else {
+			ArrayList<T> list = new ArrayList<>();
+			DateRange dateRange = range(start, end, unit);
+			while (dateRange.hasNext()) {
+				DateTime next = dateRange.next();
+				Date date = next.toJdkDate();
+				T result = func.apply(date);
+				list.add(result);
+			}
+			return list;
+		}
+	}
+
+	/**
+	 * 按日期范围遍历，执行 consumer
+	 *
+	 * @param start    起始日期时间（包括）
+	 * @param end      结束日期时间
+	 * @param unit     步进单位
+	 * @param consumer 每次遍历要执行的 consumer
+	 * @return
+	 */
+	public static void rangeConsume(Date start, Date end, final DateField unit, Consumer<Date> consumer) {
+		if (start == null || end == null || start.after(end)) {
+			return;
+		} else {
+			DateRange dateRange = range(start, end, unit);
+			while (dateRange.hasNext()) {
+				DateTime next = dateRange.next();
+				Date date = next.toJdkDate();
+				consumer.accept(date);
+			}
+		}
+	}
+
 	/**
 	 * 创建日期范围生成器
 	 *
diff --git a/hutool-core/src/test/java/cn/hutool/core/lang/RangeTest.java b/hutool-core/src/test/java/cn/hutool/core/lang/RangeTest.java
index c08e5dbb1..9feb53927 100644
--- a/hutool-core/src/test/java/cn/hutool/core/lang/RangeTest.java
+++ b/hutool-core/src/test/java/cn/hutool/core/lang/RangeTest.java
@@ -36,6 +36,32 @@ public class RangeTest {
 		Assert.assertFalse(range.hasNext());
 	}
 
+	@Test
+	public void dateRangeFuncTest() {
+		DateTime start = DateUtil.parse("2021-01-01");
+		DateTime end = DateUtil.parse("2021-01-03");
+
+		List<Integer> dayOfMonthList = DateUtil.rangeFunc(start, end, DateField.DAY_OF_YEAR, a -> DateTime.of(a).dayOfMonth());
+		Assert.assertArrayEquals(dayOfMonthList.toArray(new Integer[]{}), new Integer[]{1, 2, 3});
+
+		List<Integer> dayOfMonthList2 = DateUtil.rangeFunc(null, null, DateField.DAY_OF_YEAR, a -> DateTime.of(a).dayOfMonth());
+		Assert.assertArrayEquals(dayOfMonthList2.toArray(new Integer[]{}), new Integer[]{});
+	}
+
+	@Test
+	public void dateRangeConsumeTest() {
+		DateTime start = DateUtil.parse("2021-01-01");
+		DateTime end = DateUtil.parse("2021-01-03");
+
+		StringBuilder sb = new StringBuilder();
+		DateUtil.rangeConsume(start, end, DateField.DAY_OF_YEAR, a -> sb.append(DateTime.of(a).dayOfMonth()).append("#"));
+		Assert.assertEquals(sb.toString(), "1#2#3#");
+
+		StringBuilder sb2 = new StringBuilder();
+		DateUtil.rangeConsume(null, null, DateField.DAY_OF_YEAR, a -> sb.append(DateTime.of(a).dayOfMonth()).append("#"));
+		Assert.assertEquals(sb2.toString(), "");
+	}
+
 	@Test
 	public void dateRangeTest2() {
 		DateTime start = DateUtil.parse("2021-01-31");