Apply fallback resolution for non-hierarchical URIs such as "file:."

Includes meaningful exception message for file system resolution.

Closes gh-33124

(cherry picked from commit daea3f0eae)

spring-beans/src/main/java/org/springframework/beans/propertyeditors/PathEditor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -92,9 +92,9 @@ public class PathEditor extends PropertyEditorSupport {
 				// a file prefix (let's try as Spring resource location)
 				nioPathCandidate = !text.startsWith(ResourceUtils.FILE_URL_PREFIX);
 			}
-			catch (FileSystemNotFoundException ex) {
-				// URI scheme not registered for NIO (let's try URL
-				// protocol handlers via Spring's resource mechanism).
+			catch (FileSystemNotFoundException | IllegalArgumentException ex) {
+				// URI scheme not registered for NIO or not meeting Paths requirements:
+				// let's try URL protocol handlers via Spring's resource mechanism.
 			}
 		}
 
@@ -111,8 +111,13 @@ public class PathEditor extends PropertyEditorSupport {
 				setValue(resource.getFile().toPath());
 			}
 			catch (IOException ex) {
-				throw new IllegalArgumentException(
-						"Could not retrieve file for " + resource + ": " + ex.getMessage());
+				String msg = "Could not resolve \"" + text + "\" to 'java.nio.file.Path' for " + resource + ": " +
+						ex.getMessage();
+				if (nioPathCandidate) {
+					msg += " - In case of ambiguity, consider adding the 'file:' prefix for an explicit reference " +
+							"to a file system resource of the same name: \"file:" + text + "\"";
+				}
+				throw new IllegalArgumentException(msg);
 			}
 		}
 	}

spring-beans/src/test/java/org/springframework/beans/propertyeditors/FileEditorTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -31,54 +31,64 @@ import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException
  * @author Chris Beams
  * @author Juergen Hoeller
  */
-public class FileEditorTests {
+class FileEditorTests {
 
 	@Test
-	public void testClasspathFileName() {
+	void testClasspathFileName() {
 		PropertyEditor fileEditor = new FileEditor();
 		fileEditor.setAsText("classpath:" + ClassUtils.classPackageAsResourcePath(getClass()) + "/" +
 				ClassUtils.getShortName(getClass()) + ".class");
 		Object value = fileEditor.getValue();
-		assertThat(value instanceof File).isTrue();
+		assertThat(value).isInstanceOf(File.class);
 		File file = (File) value;
 		assertThat(file).exists();
 	}
 
 	@Test
-	public void testWithNonExistentResource() {
-		PropertyEditor propertyEditor = new FileEditor();
+	void testWithNonExistentResource() {
+		PropertyEditor fileEditor = new FileEditor();
 		assertThatIllegalArgumentException().isThrownBy(() ->
-				propertyEditor.setAsText("classpath:no_way_this_file_is_found.doc"));
+				fileEditor.setAsText("classpath:no_way_this_file_is_found.doc"));
 	}
 
 	@Test
-	public void testWithNonExistentFile() {
+	void testWithNonExistentFile() {
 		PropertyEditor fileEditor = new FileEditor();
 		fileEditor.setAsText("file:no_way_this_file_is_found.doc");
 		Object value = fileEditor.getValue();
-		assertThat(value instanceof File).isTrue();
+		assertThat(value).isInstanceOf(File.class);
 		File file = (File) value;
 		assertThat(file).doesNotExist();
 	}
 
 	@Test
-	public void testAbsoluteFileName() {
+	void testAbsoluteFileName() {
 		PropertyEditor fileEditor = new FileEditor();
 		fileEditor.setAsText("/no_way_this_file_is_found.doc");
 		Object value = fileEditor.getValue();
-		assertThat(value instanceof File).isTrue();
+		assertThat(value).isInstanceOf(File.class);
 		File file = (File) value;
 		assertThat(file).doesNotExist();
 	}
 
 	@Test
-	public void testUnqualifiedFileNameFound() {
+	void testCurrentDirectory() {
+		PropertyEditor fileEditor = new FileEditor();
+		fileEditor.setAsText("file:.");
+		Object value = fileEditor.getValue();
+		assertThat(value).isInstanceOf(File.class);
+		File file = (File) value;
+		assertThat(file).isEqualTo(new File("."));
+	}
+
+	@Test
+	void testUnqualifiedFileNameFound() {
 		PropertyEditor fileEditor = new FileEditor();
 		String fileName = ClassUtils.classPackageAsResourcePath(getClass()) + "/" +
 				ClassUtils.getShortName(getClass()) + ".class";
 		fileEditor.setAsText(fileName);
 		Object value = fileEditor.getValue();
-		assertThat(value instanceof File).isTrue();
+		assertThat(value).isInstanceOf(File.class);
 		File file = (File) value;
 		assertThat(file).exists();
 		String absolutePath = file.getAbsolutePath().replace('\\', '/');
@@ -86,13 +96,13 @@ public class FileEditorTests {
 	}
 
 	@Test
-	public void testUnqualifiedFileNameNotFound() {
+	void testUnqualifiedFileNameNotFound() {
 		PropertyEditor fileEditor = new FileEditor();
 		String fileName = ClassUtils.classPackageAsResourcePath(getClass()) + "/" +
 				ClassUtils.getShortName(getClass()) + ".clazz";
 		fileEditor.setAsText(fileName);
 		Object value = fileEditor.getValue();
-		assertThat(value instanceof File).isTrue();
+		assertThat(value).isInstanceOf(File.class);
 		File file = (File) value;
 		assertThat(file).doesNotExist();
 		String absolutePath = file.getAbsolutePath().replace('\\', '/');

spring-beans/src/test/java/org/springframework/beans/propertyeditors/PathEditorTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -19,6 +19,7 @@ package org.springframework.beans.propertyeditors;
 import java.beans.PropertyEditor;
 import java.io.File;
 import java.nio.file.Path;
+import java.nio.file.Paths;
 
 import org.junit.jupiter.api.Test;
 
@@ -31,10 +32,10 @@ import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException
  * @author Juergen Hoeller
  * @since 4.3.2
  */
-public class PathEditorTests {
+class PathEditorTests {
 
 	@Test
-	public void testClasspathPathName() {
+	void testClasspathPathName() {
 		PropertyEditor pathEditor = new PathEditor();
 		pathEditor.setAsText("classpath:" + ClassUtils.classPackageAsResourcePath(getClass()) + "/" +
 				ClassUtils.getShortName(getClass()) + ".class");
@@ -45,14 +46,14 @@ public class PathEditorTests {
 	}
 
 	@Test
-	public void testWithNonExistentResource() {
-		PropertyEditor propertyEditor = new PathEditor();
+	void testWithNonExistentResource() {
+		PropertyEditor pathEditor = new PathEditor();
 		assertThatIllegalArgumentException().isThrownBy(() ->
-				propertyEditor.setAsText("classpath:/no_way_this_file_is_found.doc"));
+				pathEditor.setAsText("classpath:/no_way_this_file_is_found.doc"));
 	}
 
 	@Test
-	public void testWithNonExistentPath() {
+	void testWithNonExistentPath() {
 		PropertyEditor pathEditor = new PathEditor();
 		pathEditor.setAsText("file:/no_way_this_file_is_found.doc");
 		Object value = pathEditor.getValue();
@@ -62,7 +63,7 @@ public class PathEditorTests {
 	}
 
 	@Test
-	public void testAbsolutePath() {
+	void testAbsolutePath() {
 		PropertyEditor pathEditor = new PathEditor();
 		pathEditor.setAsText("/no_way_this_file_is_found.doc");
 		Object value = pathEditor.getValue();
@@ -72,7 +73,7 @@ public class PathEditorTests {
 	}
 
 	@Test
-	public void testWindowsAbsolutePath() {
+	void testWindowsAbsolutePath() {
 		PropertyEditor pathEditor = new PathEditor();
 		pathEditor.setAsText("C:\\no_way_this_file_is_found.doc");
 		Object value = pathEditor.getValue();
@@ -82,7 +83,7 @@ public class PathEditorTests {
 	}
 
 	@Test
-	public void testWindowsAbsoluteFilePath() {
+	void testWindowsAbsoluteFilePath() {
 		PropertyEditor pathEditor = new PathEditor();
 		try {
 			pathEditor.setAsText("file://C:\\no_way_this_file_is_found.doc");
@@ -99,7 +100,17 @@ public class PathEditorTests {
 	}
 
 	@Test
-	public void testUnqualifiedPathNameFound() {
+	void testCurrentDirectory() {
+		PropertyEditor pathEditor = new PathEditor();
+		pathEditor.setAsText("file:.");
+		Object value = pathEditor.getValue();
+		assertThat(value).isInstanceOf(Path.class);
+		Path path = (Path) value;
+		assertThat(path).isEqualTo(Paths.get("."));
+	}
+
+	@Test
+	void testUnqualifiedPathNameFound() {
 		PropertyEditor pathEditor = new PathEditor();
 		String fileName = ClassUtils.classPackageAsResourcePath(getClass()) + "/" +
 				ClassUtils.getShortName(getClass()) + ".class";
@@ -117,7 +128,7 @@ public class PathEditorTests {
 	}
 
 	@Test
-	public void testUnqualifiedPathNameNotFound() {
+	void testUnqualifiedPathNameNotFound() {
 		PropertyEditor pathEditor = new PathEditor();
 		String fileName = ClassUtils.classPackageAsResourcePath(getClass()) + "/" +
 				ClassUtils.getShortName(getClass()) + ".clazz";