优化 IndexedComparator性能,底层实现由array变为hashMap,避免循环equals

hutool-core/src/test/java/cn/hutool/core/comparator/IndexedComparatorTest.java

@@ -0,0 +1,47 @@
+package cn.hutool.core.comparator;
+
+import cn.hutool.core.collection.CollectionUtil;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.List;
+
+public class IndexedComparatorTest {
+	@Test
+	public void sortTest() {
+		final Object[] arr ={"a", "b", new User("9", null), "1",3,null,"2"};
+		final Collection<Object> set = new HashSet<>(Arrays.asList(arr));
+
+		final List<Object> sortSet = CollectionUtil.sort(set, new IndexedComparator<>(arr));
+
+		Assert.assertEquals("a", sortSet.get(0));
+		Assert.assertEquals( new User("9", null), sortSet.get(2));
+		Assert.assertEquals(3, sortSet.get(4));
+		Assert.assertNull(sortSet.get(5));
+	}
+
+	@Test
+	public void reversedTest() {
+		final Object[] arr ={"a", "b", new User("9", null), "1",3,null,"2"};
+		final Collection<Object> set = new HashSet<>(Arrays.asList(arr));
+
+		final List<Object> sortSet = CollectionUtil.sort(set, new IndexedComparator<>(arr).reversed());
+
+		Assert.assertEquals("a", sortSet.get(6));
+		Assert.assertNull(sortSet.get(1));
+		Assert.assertEquals( new User("9", null), sortSet.get(4));
+		Assert.assertEquals(3, sortSet.get(2));
+	}
+
+	@Data
+	@AllArgsConstructor
+	static class User{
+		private String a;
+		private String b;
+	}
+}