add methods

hutool-core/src/main/java/org/dromara/hutool/core/date/Quarter.java

@@ -16,6 +16,10 @@
 
 package org.dromara.hutool.core.date;
 
+import org.dromara.hutool.core.lang.Assert;
+
+import java.time.temporal.ChronoField;
+
 /**
  * 季度枚举
  *
@@ -84,4 +88,56 @@ public enum Quarter {
 				return null;
 		}
 	}
+
+	/**
+	 * 根据给定的月份值返回对应的季度
+	 *
+	 * @param monthValue 月份值，取值范围为1到12
+	 * @return 对应的季度
+	 * @throws IllegalArgumentException 如果月份值不在有效范围内（1到12），将抛出异常
+	 */
+	public static Quarter fromMonth(final int monthValue) {
+		ChronoField.MONTH_OF_YEAR.checkValidValue(monthValue);
+		return of(computeQuarterValueInternal(monthValue));
+	}
+
+	/**
+	 * 根据给定的月份返回对应的季度
+	 *
+	 * @param month 月份
+	 * @return 对应的季度
+	 */
+	public static Quarter fromMonth(final Month month) {
+		Assert.notNull(month);
+		final int monthValue = month.getValue();
+		return of(computeQuarterValueInternal(monthValue));
+	}
+
+	/**
+	 * 该季度的第一个月
+	 *
+	 * @return 结果
+	 */
+	public Month firstMonth() {
+		return Month.of(value * 3 - 3);
+	}
+
+	/**
+	 * 该季度最后一个月
+	 *
+	 * @return 结果
+	 */
+	public Month lastMonth() {
+		return Month.of(value * 3 - 1);
+	}
+
+	/**
+	 * 计算给定月份对应的季度值
+	 *
+	 * @param monthValue 月份值，取值范围为1到12
+	 * @return 对应的季度值
+	 */
+	private static int computeQuarterValueInternal(final int monthValue) {
+		return (monthValue - 1) / 3 + 1;
+	}
 }

hutool-core/src/test/java/org/dromara/hutool/core/date/QuarterTest.java

@@ -0,0 +1,86 @@
+package org.dromara.hutool.core.date;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Objects;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class QuarterTest {
+	@Test
+	void testQ1() {
+		final Quarter quarter = Quarter.of(1);
+		assertSame(Quarter.Q1, quarter);
+		assertSame(quarter, Quarter.valueOf("Q1"));
+		assertEquals(1, Objects.requireNonNull(quarter).getValue());
+		assertEquals("Q1", quarter.name());
+
+		assertNull(Quarter.of(0));
+
+		final Month firstMonth = quarter.firstMonth();
+		assertEquals(Month.JANUARY, firstMonth);
+
+		final Month lastMonth = quarter.lastMonth();
+		assertEquals(Month.MARCH, lastMonth);
+	}
+
+	@Test
+	void testQ2() {
+		final Quarter quarter = Quarter.of(2);
+		assertSame(Quarter.Q2, quarter);
+		assertSame(quarter, Quarter.valueOf("Q2"));
+		assertEquals(2, Objects.requireNonNull(quarter).getValue());
+		assertEquals("Q2", quarter.name());
+
+		assertNull(Quarter.of(5));
+
+		// ==========
+
+		final Month firstMonth = quarter.firstMonth();
+		assertEquals(Month.APRIL, firstMonth);
+
+		// ==========
+
+		final Month lastMonth = quarter.lastMonth();
+		assertEquals(Month.JUNE, lastMonth);
+	}
+
+	@Test
+	void testQ3() {
+		final Quarter quarter = Quarter.of(3);
+		assertSame(Quarter.Q3, quarter);
+		assertSame(quarter, Quarter.valueOf("Q3"));
+		assertEquals(3, Objects.requireNonNull(quarter).getValue());
+		assertEquals("Q3", quarter.name());
+
+		assertThrows(IllegalArgumentException.class, () -> {
+			Quarter.valueOf("Abc");
+		});
+
+		final Month firstMonth = quarter.firstMonth();
+		assertEquals(Month.JULY, firstMonth);
+
+		final Month lastMonth = quarter.lastMonth();
+		assertEquals(Month.SEPTEMBER, lastMonth);
+	}
+
+	@Test
+	void testQ4() {
+		final Quarter quarter = Quarter.of(4);
+		assertSame(Quarter.Q4, quarter);
+		assertSame(quarter, Quarter.valueOf("Q4"));
+		assertEquals(4, quarter.getValue());
+		assertEquals("Q4", quarter.name());
+
+		assertThrows(IllegalArgumentException.class, () -> {
+			Quarter.valueOf("Q5");
+		});
+
+		final Month firstMonth = quarter.firstMonth();
+		assertEquals(Month.OCTOBER, firstMonth);
+
+		final Month lastMonth = quarter.lastMonth();
+		assertEquals(Month.DECEMBER, lastMonth);
+	}
+
+}