spring-projectsGH-8659: Fix the WatchServiceDirectoryScanner to detect new file after renaming the sub-folder of the watched folder (Java 7 WatchService)

Author: pziobron

spring-integration-file/src/main/java/org/springframework/integration/file/FileReadingMessageSource.java

@@ -533,6 +533,10 @@ private void processFilesFromNormalEvent(Set<File> files, File parentDir, WatchE
 			logger.debug(() -> "Watch event [" + event.kind() + "] for file [" + file + "]");
 
 			if (StandardWatchEventKinds.ENTRY_DELETE.equals(event.kind())) {
+				if (this.pathKeys.containsKey(file.toPath())) {
+					WatchKey watchKey = this.pathKeys.remove(file.toPath());
+					watchKey.cancel();
+				}
 				if (getFilter() instanceof ResettableFileListFilter<File> resettableFileListFilter) {
 					resettableFileListFilter.remove(file);
 				}
@@ -554,7 +558,7 @@ private void processFilesFromNormalEvent(Set<File> files, File parentDir, WatchE
 				}
 				else {
 					logger.debug(() -> "A file [" + file + "] for the event [" + event.kind() +
-							"] doesn't exist. Ignored.");
+							"] doesn't exist. Ignored. Maybe DELETE event is not watched ?");
 				}
 			}
 		}

spring-integration-file/src/test/java/org/springframework/integration/file/WatchServiceDirectoryScannerTests.java

@@ -130,9 +130,9 @@ public boolean remove(File fileToRemove) {
 		File top2 = File.createTempFile("tmp", null, this.rootDir);
 		File foo2 = File.createTempFile("foo", ".txt", this.foo);
 		File bar2 = File.createTempFile("bar", ".txt", this.bar);
-		File baz = new File(this.foo, "baz");
-		baz.mkdir();
-		File baz1 = File.createTempFile("baz", ".txt", baz);
+		File bazA = new File(this.foo, "bazA");
+		bazA.mkdir();
+		File baz1 = File.createTempFile("baz", ".txt", bazA);
 		files = scanner.listFiles(this.rootDir);
 		int n = 0;
 		Set<File> accum = new HashSet<>(files);
@@ -170,7 +170,7 @@ public boolean remove(File fileToRemove) {
 
 		assertThat(accum).containsAll(filesForOverflow);
 
-		File baz2 = File.createTempFile("baz2", ".txt", baz);
+		File baz2 = File.createTempFile("baz2", ".txt", bazA);
 
 		n = 0;
 		while (n++ < 300 && accum.size() < 605) {
@@ -207,7 +207,19 @@ public boolean remove(File fileToRemove) {
 
 		assertThat(removeFileLatch.await(10, TimeUnit.SECONDS)).isTrue();
 
-		File baz3 = File.createTempFile("baz3", ".txt", baz);
+		File bazB = new File(this.foo, "bazB");
+		bazA.renameTo(bazB);
+		File baz3 = File.createTempFile("baz3", ".txt", bazB);
+
+		while (n++ < 300 && files.size() < 1) {
+			Thread.sleep(100);
+			files = scanner.listFiles(this.rootDir);
+			accum.addAll(files);
+		}
+
+		assertThat(files).hasSize(1).contains(baz3);
+
+		File baz4 = File.createTempFile("baz4", ".txt", bazB);
 
 		n = 0;
 		Message<File> fileMessage = null;
@@ -216,7 +228,7 @@ public boolean remove(File fileToRemove) {
 		}
 
 		assertThat(fileMessage).isNotNull();
-		assertThat(fileMessage.getPayload()).isEqualTo(baz3);
+		assertThat(fileMessage.getPayload()).isEqualTo(baz4);
 		assertThat(fileMessage.getHeaders().get(FileHeaders.RELATIVE_PATH, String.class))
 				.startsWith(TestUtils.applySystemFileSeparator("foo/baz/"));