From 9267c8217a7bbc484866d9b27f2f5ebf7d9fbbf5 Mon Sep 17 00:00:00 2001
From: easepan <easepan@qq.com>
Date: Wed, 9 Sep 2020 18:50:22 +0800
Subject: [PATCH] feat: comparator for chinese pinyin

---
 .../hutool/core/comparator/CompareUtil.java   | 34 +++++++++++++++++++
 .../core/comparator/CompareUtilTest.java      | 22 ++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/hutool-core/src/main/java/cn/hutool/core/comparator/CompareUtil.java b/hutool-core/src/main/java/cn/hutool/core/comparator/CompareUtil.java
index c592e7a30..5c0766073 100644
--- a/hutool-core/src/main/java/cn/hutool/core/comparator/CompareUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/comparator/CompareUtil.java
@@ -1,6 +1,10 @@
 package cn.hutool.core.comparator;
 
+import java.text.Collator;
 import java.util.Comparator;
+import java.util.Locale;
+import java.util.Objects;
+import java.util.function.Function;
 
 /**
  * 比较工具类
@@ -108,4 +112,34 @@ public class CompareUtil {
 
 		return result;
 	}
+
+	/**
+	 * 中文比较器
+	 *
+	 * @param keyExtractor 从对象中提取中文
+	 * @param <T> 对象类型
+	 *
+	 * @return 中文比较器
+	 */
+	public static <T> Comparator<T> comparingPinyin(Function<T, String> keyExtractor) {
+		return comparingPinyin(keyExtractor, false);
+	}
+
+	/**
+	 * 中文比较器
+	 *
+	 * @param keyExtractor 从对象中提取中文
+	 * @param reverse 是否反序
+	 * @param <T> 对象类型
+	 *
+	 * @return 中文比较器
+	 */
+	public static <T> Comparator<T> comparingPinyin(Function<T, String> keyExtractor, boolean reverse) {
+		Objects.requireNonNull(keyExtractor);
+		Collator chineseCollator = Collator.getInstance(Locale.CHINESE);
+		if (reverse) {
+			return (o1, o2) -> chineseCollator.compare(keyExtractor.apply(o2), keyExtractor.apply(o1));
+		}
+		return (o1, o2) -> chineseCollator.compare(keyExtractor.apply(o1), keyExtractor.apply(o2));
+	}
 }
diff --git a/hutool-core/src/test/java/cn/hutool/core/comparator/CompareUtilTest.java b/hutool-core/src/test/java/cn/hutool/core/comparator/CompareUtilTest.java
index b1378be80..7527b0976 100644
--- a/hutool-core/src/test/java/cn/hutool/core/comparator/CompareUtilTest.java
+++ b/hutool-core/src/test/java/cn/hutool/core/comparator/CompareUtilTest.java
@@ -1,8 +1,13 @@
 package cn.hutool.core.comparator;
 
+import cn.hutool.core.collection.ListUtil;
 import org.junit.Assert;
 import org.junit.Test;
 
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
 public class CompareUtilTest {
 
 	@Test
@@ -13,4 +18,21 @@ public class CompareUtilTest {
 		compare = CompareUtil.compare(null, "a", false);
 		Assert.assertTrue(compare < 0);
 	}
+
+	@Test
+	public void comparingPinyin() {
+		List<String> list = new ArrayList<>();
+		Collections.addAll(list, "成都", "北京", "上海", "深圳");
+
+		List<String> ascendingOrderResult = ListUtil.of("北京", "成都", "上海", "深圳");
+		List<String> descendingOrderResult = ListUtil.of("深圳", "上海", "成都", "北京");
+
+		// 正序
+		list.sort(CompareUtil.comparingPinyin(e -> e));
+		Assert.assertEquals(list, ascendingOrderResult);
+
+		// 反序
+		list.sort(CompareUtil.comparingPinyin(e -> e, true));
+		Assert.assertEquals(list, descendingOrderResult);
+	}
 }