Merge pull request #636 from ivanwick/issue-262-delete-temp-file-on-c…

…lose

Delete temporary file on close

jhdf/src/main/java/io/jhdf/HdfFile.java

@@ -36,10 +36,8 @@
 import java.nio.ByteBuffer;
 import java.nio.channels.FileChannel;
 import java.nio.file.FileSystems;
-import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-import java.nio.file.StandardCopyOption;
 import java.nio.file.StandardOpenOption;
 import java.util.HashSet;
 import java.util.Iterator;
@@ -156,24 +154,15 @@ private HdfFile(HdfBackingStorage hdfBackingStorage) {
 
 	/**
 	 * Opens an {@link HdfFile} from an {@link InputStream}. The stream will be read fully into a temporary file. The
-	 * file will be cleaned up at application exit.
+	 * file will be deleted when the HdfFile is closed, or at application exit if it was never closed.
 	 *
 	 * @param inputStream the {@link InputStream} to read
 	 * @return HdfFile instance
 	 * @see HdfFile#fromBytes(byte[])
 	 * @see HdfFile#fromByteBuffer(ByteBuffer)
 	 */
 	public static HdfFile fromInputStream(InputStream inputStream) {
-		try {
-			Path tempFile = Files.createTempFile(null, "-stream.hdf5"); // null random file name
-			logger.info("Creating temp file [{}]", tempFile.toAbsolutePath());
-			tempFile.toFile().deleteOnExit(); // Auto cleanup
-			Files.copy(inputStream, tempFile, StandardCopyOption.REPLACE_EXISTING);
-			logger.debug("Read stream to temp file [{}]", tempFile.toAbsolutePath());
-			return new HdfFile(tempFile);
-		} catch (IOException e) {
-			throw new HdfException("Failed to open input stream", e);
-		}
+		return TempHdfFile.fromInputStream(inputStream);
 	}
 
 	public HdfFile(Path hdfFile) {

jhdf/src/main/java/io/jhdf/TempHdfFile.java

@@ -0,0 +1,51 @@
+/*
+ * This file is part of jHDF. A pure Java library for accessing HDF5 files.
+ *
+ * https://jhdf.io
+ *
+ * Copyright (c) 2024 James Mudd
+ *
+ * MIT License see 'LICENSE' file
+ */
+package io.jhdf;
+
+import io.jhdf.exceptions.HdfException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardCopyOption;
+
+class TempHdfFile extends HdfFile {
+	private static final Logger logger = LoggerFactory.getLogger(TempHdfFile.class);
+
+	private TempHdfFile(Path tempFile) {
+		super(tempFile);
+	}
+
+	@Override
+	public void close() {
+		super.close();
+		logger.info("Deleting temp file on close [{}]", getFileAsPath().toAbsolutePath());
+		boolean deleteSuccess = getFile().delete();
+		if (!deleteSuccess) {
+			logger.warn("Could not delete temp file [{}]", getFileAsPath().toAbsolutePath());
+		}
+	}
+
+	public static TempHdfFile fromInputStream(InputStream inputStream) {
+		try {
+			Path tempFile = Files.createTempFile(null, "-stream.hdf5"); // null random file name
+			logger.info("Creating temp file [{}]", tempFile.toAbsolutePath());
+			tempFile.toFile().deleteOnExit(); // Auto cleanup in case close() is never called
+			Files.copy(inputStream, tempFile, StandardCopyOption.REPLACE_EXISTING);
+			logger.debug("Read stream to temp file [{}]", tempFile.toAbsolutePath());
+			return new TempHdfFile(tempFile);
+		} catch (IOException e) {
+			throw new HdfException("Failed to open input stream", e);
+		}
+	}
+}

jhdf/src/test/java/io/jhdf/HdfFileTest.java

@@ -48,7 +48,9 @@
 import static org.hamcrest.Matchers.sameInstance;
 import static org.hamcrest.Matchers.startsWith;
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 class HdfFileTest {
 
@@ -316,6 +318,17 @@ void testReadingFromStreamThrowsWhenStreamCantBeRead() throws IOException {
 		}
 	}
 
+	@Test
+	void testReadingFromStreamDeletesTempFileOnClose() throws IOException {
+		File tempFile;
+		try (InputStream inputStream = this.getClass().getResource(HDF5_TEST_FILE_PATH).openStream();
+			 HdfFile hdfFile = HdfFile.fromInputStream(inputStream)) {
+			tempFile = hdfFile.getFile();
+			assertTrue(tempFile.exists());
+		}
+		assertFalse(tempFile.exists());
+	}
+
 	@Test
 	void testLoadingInMemoryFile() throws IOException, URISyntaxException {
 		Path path = Paths.get(this.getClass().getResource(HDF5_TEST_FILE_PATH).toURI());