Merge pull request #18883 from izeye

* pr/18883:
  Use try-with-resources blocks in JarFileArchiveTests

Closes gh-18883

spring-boot-project/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/archive/JarFileArchiveTests.java

@@ -98,48 +98,48 @@ class JarFileArchiveTests {
 	@Test
 	void getNestedArchive() throws Exception {
 		Entry entry = getEntriesMap(this.archive).get("nested.jar");
-		Archive nested = this.archive.getNestedArchive(entry);
+		try (Archive nested = this.archive.getNestedArchive(entry)) {
 			assertThat(nested.getUrl().toString()).isEqualTo("jar:" + this.rootJarFileUrl + "!/nested.jar!/");
-		((JarFileArchive) nested).close();
+		}
 	}
 
 	@Test
 	void getNestedUnpackedArchive() throws Exception {
 		setup(true);
 		Entry entry = getEntriesMap(this.archive).get("nested.jar");
-		Archive nested = this.archive.getNestedArchive(entry);
+		try (Archive nested = this.archive.getNestedArchive(entry)) {
 			assertThat(nested.getUrl().toString()).startsWith("file:");
 			assertThat(nested.getUrl().toString()).endsWith("/nested.jar");
-		((JarFileArchive) nested).close();
+		}
 	}
 
 	@Test
 	void unpackedLocationsAreUniquePerArchive() throws Exception {
 		setup(true);
 		Entry entry = getEntriesMap(this.archive).get("nested.jar");
-		Archive firstNested = this.archive.getNestedArchive(entry);
-		URL firstNestedUrl = firstNested.getUrl();
-		((JarFileArchive) firstNested).close();
+		URL firstNestedUrl;
+		try (Archive firstNested = this.archive.getNestedArchive(entry)) {
+			firstNestedUrl = firstNested.getUrl();
+		}
 		this.archive.close();
 		setup(true);
 		entry = getEntriesMap(this.archive).get("nested.jar");
-		Archive secondNested = this.archive.getNestedArchive(entry);
+		try (Archive secondNested = this.archive.getNestedArchive(entry)) {
 			URL secondNestedUrl = secondNested.getUrl();
 			assertThat(secondNestedUrl).isNotEqualTo(firstNestedUrl);
-		((JarFileArchive) secondNested).close();
+		}
 	}
 
 	@Test
 	void unpackedLocationsFromSameArchiveShareSameParent() throws Exception {
 		setup(true);
-		Archive nestedArchive = this.archive.getNestedArchive(getEntriesMap(this.archive).get("nested.jar"));
-		File nested = new File(nestedArchive.getUrl().toURI());
+		try (Archive nestedArchive = this.archive.getNestedArchive(getEntriesMap(this.archive).get("nested.jar"));
 				Archive anotherNestedArchive = this.archive
-				.getNestedArchive(getEntriesMap(this.archive).get("another-nested.jar"));
+						.getNestedArchive(getEntriesMap(this.archive).get("another-nested.jar"))) {
+			File nested = new File(nestedArchive.getUrl().toURI());
 			File anotherNested = new File(anotherNestedArchive.getUrl().toURI());
 			assertThat(nested.getParent()).isEqualTo(anotherNested.getParent());
-		((JarFileArchive) nestedArchive).close();
-		((JarFileArchive) anotherNestedArchive).close();
+		}
 	}
 
 	@Test
@@ -156,9 +156,9 @@ class JarFileArchiveTests {
 	}
 
 	@Test
-	void nestedZip64ArchivesAreHandledGracefully() throws IOException {
+	void nestedZip64ArchivesAreHandledGracefully() throws Exception {
 		File file = new File(this.tempDir, "test.jar");
-		JarOutputStream output = new JarOutputStream(new FileOutputStream(file));
+		try (JarOutputStream output = new JarOutputStream(new FileOutputStream(file))) {
 			JarEntry zip64JarEntry = new JarEntry("nested/zip64.jar");
 			output.putNextEntry(zip64JarEntry);
 			byte[] zip64JarData = writeZip64Jar();
@@ -170,26 +170,26 @@ class JarFileArchiveTests {
 			zip64JarEntry.setCrc(crc32.getValue());
 			output.write(zip64JarData);
 			output.closeEntry();
-		output.close();
-		JarFileArchive jarFileArchive = new JarFileArchive(file);
-		Archive nestedArchive = jarFileArchive.getNestedArchive(getEntriesMap(jarFileArchive).get("nested/zip64.jar"));
+		}
+		try (JarFileArchive jarFileArchive = new JarFileArchive(file);
+				Archive nestedArchive = jarFileArchive
+						.getNestedArchive(getEntriesMap(jarFileArchive).get("nested/zip64.jar"))) {
 			Iterator<Entry> it = nestedArchive.iterator();
 			for (int i = 0; i < 65537; i++) {
 				assertThat(it.hasNext()).as(i + "nth file is present").isTrue();
 				it.next();
 			}
-		((JarFileArchive) nestedArchive).close();
-		jarFileArchive.close();
+		}
 	}
 
 	private byte[] writeZip64Jar() throws IOException {
 		ByteArrayOutputStream bytes = new ByteArrayOutputStream();
-		JarOutputStream jarOutput = new JarOutputStream(bytes);
+		try (JarOutputStream jarOutput = new JarOutputStream(bytes)) {
 			for (int i = 0; i < 65537; i++) {
 				jarOutput.putNextEntry(new JarEntry(i + ".dat"));
 				jarOutput.closeEntry();
 			}
-		jarOutput.close();
+		}
 		return bytes.toByteArray();
 	}