Add kotlin extensions for Sort.

src/main/kotlin/org/springframework/data/domain/SortExtensions.kt

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2026-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.domain
+
+import org.springframework.data.mapping.toDotPath
+import kotlin.reflect.KProperty
+
+/**
+ * Creates an ascending [Sort] based on this [KProperty].
+ *
+ * @author Yejun Ho
+ * @since 4.0.3
+ */
+fun KProperty<*>.asc(): Sort =
+    Sort.by(Sort.Direction.ASC, this.toDotPath())
+
+/**
+ * Creates a descending [Sort] based on this [KProperty].
+ *
+ * @author Yejun Ho
+ * @since 4.0.3
+ */
+fun KProperty<*>.desc(): Sort =
+    Sort.by(Sort.Direction.DESC, this.toDotPath())

src/test/kotlin/org/springframework/data/domain/SortExtensionsTests.kt

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+/*
+ * Copyright 2026-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.domain
+
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+
+/**
+ * Unit tests for SortExtensions.
+ *
+ * @author Yejun Ho
+ */
+class SortExtensionsTests {
+
+    @Test // GH-3445
+    fun `KProperty#asc() extension should create ascending Java Sort`() {
+        assertThat(Book::title.asc()).isEqualTo(Sort.by(Sort.Direction.ASC, Book::title.name))
+    }
+
+    @Test // GH-3445
+    fun `KProperty#desc() extension should create descending Java Sort`() {
+        assertThat(Book::title.desc()).isEqualTo(Sort.by(Sort.Direction.DESC, Book::title.name))
+    }
+
+    class Book(val title: String)
+}