Polish "Use try-with-resources to close resources automatically"

- Apply code formatting
- Use try-with-resources in many other places that were missed in the
  pull request

Closes gh-8045

spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/BuildPropertiesWriter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -48,18 +48,9 @@ public final class BuildPropertiesWriter {
 	public void writeBuildProperties(ProjectDetails projectDetails) throws IOException {
 		Properties properties = createBuildInfo(projectDetails);
 		createFileIfNecessary(this.outputFile);
-		FileOutputStream outputStream = new FileOutputStream(this.outputFile);
-		try {
+		try (FileOutputStream outputStream = new FileOutputStream(this.outputFile)) {
 			properties.store(outputStream, "Properties");
 		}
-		finally {
-			try {
-				outputStream.close();
-			}
-			catch (IOException ex) {
-				// Continue
-			}
-		}
 	}
 
 	private void createFileIfNecessary(File file) throws IOException {

spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/FileUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -64,18 +64,14 @@ public abstract class FileUtils {
 	 */
 	public static String sha1Hash(File file) throws IOException {
 		try {
-			DigestInputStream inputStream = new DigestInputStream(
-					new FileInputStream(file), MessageDigest.getInstance("SHA-1"));
-			try {
+			try (DigestInputStream inputStream = new DigestInputStream(
+					new FileInputStream(file), MessageDigest.getInstance("SHA-1"))) {
 				byte[] buffer = new byte[4098];
 				while (inputStream.read(buffer) != -1) {
 					// Read the entire stream
 				}
 				return bytesToHex(inputStream.getMessageDigest().digest());
 			}
-			finally {
-				inputStream.close();
-			}
 		}
 		catch (NoSuchAlgorithmException ex) {
 			throw new IllegalStateException(ex);

spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/JarWriter.java

@@ -49,7 +49,7 @@ import java.util.zip.ZipEntry;
  * @author Phillip Webb
  * @author Andy Wilkinson
  */
-public class JarWriter implements LoaderClassesWriter {
+public class JarWriter implements LoaderClassesWriter, AutoCloseable {
 
 	private static final String NESTED_LOADER_JAR = "META-INF/loader/spring-boot-loader.jar";
 
@@ -128,23 +128,24 @@ public class JarWriter implements LoaderClassesWriter {
 		Enumeration<JarEntry> entries = jarFile.entries();
 		while (entries.hasMoreElements()) {
 			JarEntry entry = entries.nextElement();
-			ZipHeaderPeekInputStream inputStream = new ZipHeaderPeekInputStream(
-					jarFile.getInputStream(entry));
-			try {
-				if (inputStream.hasZipHeader() && entry.getMethod() != ZipEntry.STORED) {
-					new CrcAndSize(inputStream).setupStoredEntry(entry);
-					inputStream.close();
-					inputStream = new ZipHeaderPeekInputStream(
-							jarFile.getInputStream(entry));
-				}
+			setUpStoredEntryIfNecessary(jarFile, entry);
+			try (ZipHeaderPeekInputStream inputStream = new ZipHeaderPeekInputStream(
+					jarFile.getInputStream(entry))) {
 				EntryWriter entryWriter = new InputStreamEntryWriter(inputStream, true);
 				JarEntry transformedEntry = entryTransformer.transform(entry);
 				if (transformedEntry != null) {
 					writeEntry(transformedEntry, entryWriter);
 				}
 			}
-			finally {
-				inputStream.close();
+		}
+	}
+
+	private void setUpStoredEntryIfNecessary(JarFile jarFile, JarEntry entry)
+			throws IOException {
+		try (ZipHeaderPeekInputStream inputStream = new ZipHeaderPeekInputStream(
+				jarFile.getInputStream(entry))) {
+			if (inputStream.hasZipHeader() && entry.getMethod() != ZipEntry.STORED) {
+				new CrcAndSize(inputStream).setupStoredEntry(entry);
 			}
 		}
 	}
@@ -234,6 +235,7 @@ public class JarWriter implements LoaderClassesWriter {
 	 * Close the writer.
 	 * @throws IOException if the file cannot be closed
 	 */
+	@Override
 	public void close() throws IOException {
 		this.jarOutput.close();
 	}

spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/MainClassFinder.java

@@ -141,8 +141,7 @@ public abstract class MainClassFinder {
 		while (!stack.isEmpty()) {
 			File file = stack.pop();
 			if (file.isFile()) {
-				InputStream inputStream = new FileInputStream(file);
-				try {
+				try (InputStream inputStream = new FileInputStream(file)) {
 					ClassDescriptor classDescriptor = createClassDescriptor(inputStream);
 					if (classDescriptor != null && classDescriptor.isMainMethodFound()) {
 						String className = convertToClassName(file.getAbsolutePath(),
@@ -154,9 +153,6 @@ public abstract class MainClassFinder {
 						}
 					}
 				}
-				finally {
-					inputStream.close();
-				}
 			}
 			if (file.isDirectory()) {
 				pushAllSorted(stack, file.listFiles(PACKAGE_FOLDER_FILTER));
@@ -240,9 +236,8 @@ public abstract class MainClassFinder {
 		List<JarEntry> classEntries = getClassEntries(jarFile, classesLocation);
 		Collections.sort(classEntries, new ClassEntryComparator());
 		for (JarEntry entry : classEntries) {
-			InputStream inputStream = new BufferedInputStream(
-					jarFile.getInputStream(entry));
-			try {
+			try (InputStream inputStream = new BufferedInputStream(
+					jarFile.getInputStream(entry))) {
 				ClassDescriptor classDescriptor = createClassDescriptor(inputStream);
 				if (classDescriptor != null && classDescriptor.isMainMethodFound()) {
 					String className = convertToClassName(entry.getName(),
@@ -254,9 +249,6 @@ public abstract class MainClassFinder {
 					}
 				}
 			}
-			finally {
-				inputStream.close();
-			}
 		}
 		return null;
 	}

spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/Repackager.java

@@ -184,13 +184,9 @@ public class Repackager {
 		}
 		destination.delete();
 		try {
-			JarFile jarFileSource = new JarFile(workingSource);
-			try {
+			try (JarFile jarFileSource = new JarFile(workingSource)) {
 				repackage(jarFileSource, destination, libraries, launchScript);
 			}
-			finally {
-				jarFileSource.close();
-			}
 		}
 		finally {
 			if (!this.backupSource && !this.source.equals(workingSource)) {
@@ -221,21 +217,16 @@ public class Repackager {
 	}
 
 	private boolean alreadyRepackaged() throws IOException {
-		JarFile jarFile = new JarFile(this.source);
-		try {
+		try (JarFile jarFile = new JarFile(this.source)) {
 			Manifest manifest = jarFile.getManifest();
 			return (manifest != null && manifest.getMainAttributes()
 					.getValue(BOOT_VERSION_ATTRIBUTE) != null);
 		}
-		finally {
-			jarFile.close();
-		}
 	}
 
 	private void repackage(JarFile sourceJar, File destination, Libraries libraries,
 			LaunchScript launchScript) throws IOException {
-		JarWriter writer = new JarWriter(destination, launchScript);
-		try {
+		try (JarWriter writer = new JarWriter(destination, launchScript)) {
 			final List<Library> unpackLibraries = new ArrayList<>();
 			final List<Library> standardLibraries = new ArrayList<>();
 			libraries.doWithLibraries(new LibraryCallback() {
@@ -256,14 +247,6 @@ public class Repackager {
 			});
 			repackage(sourceJar, writer, unpackLibraries, standardLibraries);
 		}
-		finally {
-			try {
-				writer.close();
-			}
-			catch (Exception ex) {
-				// Ignore
-			}
-		}
 	}
 
 	private void repackage(JarFile sourceJar, JarWriter writer,
@@ -309,13 +292,9 @@ public class Repackager {
 
 	private boolean isZip(File file) {
 		try {
-			FileInputStream fileInputStream = new FileInputStream(file);
-			try {
+			try (FileInputStream fileInputStream = new FileInputStream(file)) {
 				return isZip(fileInputStream);
 			}
-			finally {
-				fileInputStream.close();
-			}
 		}
 		catch (IOException ex) {
 			return false;

spring-boot-tools/spring-boot-loader-tools/src/test/java/org/springframework/boot/loader/tools/FileUtilsTests.java

@@ -102,13 +102,9 @@ public class FileUtilsTests {
 	@Test
 	public void hash() throws Exception {
 		File file = this.temporaryFolder.newFile();
-		OutputStream outputStream = new FileOutputStream(file);
-		try {
+		try (OutputStream outputStream = new FileOutputStream(file)) {
 			outputStream.write(new byte[] { 1, 2, 3 });
 		}
-		finally {
-			outputStream.close();
-		}
 		assertThat(FileUtils.sha1Hash(file))
 				.isEqualTo("7037807198c22a7d2b0807371d763779a84fdfcf");
 	}

spring-boot-tools/spring-boot-loader-tools/src/test/java/org/springframework/boot/loader/tools/RepackagerTests.java

@@ -455,17 +455,14 @@ public class RepackagerTests {
 				callback.library(new Library(nestedFile, LibraryScope.COMPILE));
 			}
 		});
-		JarFile jarFile = new JarFile(file);
-		try {
+
+		try (JarFile jarFile = new JarFile(file)) {
 			assertThat(
 					jarFile.getEntry("BOOT-INF/lib/" + nestedFile.getName()).getMethod())
 							.isEqualTo(ZipEntry.STORED);
 			assertThat(jarFile.getEntry("BOOT-INF/classes/test/nested.jar").getMethod())
 					.isEqualTo(ZipEntry.STORED);
 		}
-		finally {
-			jarFile.close();
-		}
 	}
 
 	@Test
@@ -508,15 +505,12 @@ public class RepackagerTests {
 			}
 
 		});
-		JarFile jarFile = new JarFile(file);
-		try {
+
+		try (JarFile jarFile = new JarFile(file)) {
 			assertThat(
 					jarFile.getEntry("BOOT-INF/lib/" + nestedFile.getName()).getComment())
 							.startsWith("UNPACK:");
 		}
-		finally {
-			jarFile.close();
-		}
 	}
 
 	@Test
@@ -542,14 +536,10 @@ public class RepackagerTests {
 			}
 
 		});
-		JarFile jarFile = new JarFile(file);
-		try {
+		try (JarFile jarFile = new JarFile(file)) {
 			assertThat(jarFile.getEntry("BOOT-INF/lib/" + nestedFile.getName()).getSize())
 					.isEqualTo(sourceLength);
 		}
-		finally {
-			jarFile.close();
-		}
 	}
 
 	@Test
@@ -561,13 +551,9 @@ public class RepackagerTests {
 		File dest = this.temporaryFolder.newFile("dest.jar");
 		Repackager repackager = new Repackager(source);
 		repackager.repackage(dest, NO_LIBRARIES);
-		JarFile jarFile = new JarFile(dest);
-		try {
+		try (JarFile jarFile = new JarFile(dest)) {
 			assertThat(jarFile.getEntry("META-INF/INDEX.LIST")).isNull();
 		}
-		finally {
-			jarFile.close();
-		}
 	}
 
 	@Test
@@ -603,14 +589,10 @@ public class RepackagerTests {
 		File dest = this.temporaryFolder.newFile("dest.jar");
 		Repackager repackager = new Repackager(source);
 		repackager.repackage(dest, NO_LIBRARIES);
-		JarFile jarFile = new JarFile(dest);
-		try {
+		try (JarFile jarFile = new JarFile(dest)) {
 			assertThat(jarFile.getEntry("META-INF/aop.xml")).isNull();
 			assertThat(jarFile.getEntry("BOOT-INF/classes/META-INF/aop.xml")).isNotNull();
 		}
-		finally {
-			jarFile.close();
-		}
 	}
 
 	private boolean hasLauncherClasses(File file) throws IOException {
@@ -623,23 +605,15 @@ public class RepackagerTests {
 	}
 
 	private JarEntry getEntry(File file, String name) throws IOException {
-		JarFile jarFile = new JarFile(file);
-		try {
+		try (JarFile jarFile = new JarFile(file)) {
 			return jarFile.getJarEntry(name);
 		}
-		finally {
-			jarFile.close();
-		}
 	}
 
 	private Manifest getManifest(File file) throws IOException {
-		JarFile jarFile = new JarFile(file);
-		try {
+		try (JarFile jarFile = new JarFile(file)) {
 			return jarFile.getManifest();
 		}
-		finally {
-			jarFile.close();
-		}
 	}
 
 	private static class MockLauncherScript implements LaunchScript {

spring-boot-tools/spring-boot-loader-tools/src/test/java/org/springframework/boot/loader/tools/TestJarFile.java

@@ -65,25 +65,17 @@ public class TestJarFile {
 	public void addFile(String filename, File fileToCopy) throws IOException {
 		File file = getFilePath(filename);
 		file.getParentFile().mkdirs();
-		InputStream inputStream = new FileInputStream(fileToCopy);
-		try {
+		try (InputStream inputStream = new FileInputStream(fileToCopy)) {
 			copyToFile(inputStream, file);
 		}
-		finally {
-			inputStream.close();
-		}
 	}
 
 	public void addManifest(Manifest manifest) throws IOException {
 		File manifestFile = new File(this.jarSource, "META-INF/MANIFEST.MF");
 		manifestFile.getParentFile().mkdirs();
-		OutputStream outputStream = new FileOutputStream(manifestFile);
-		try {
+		try (OutputStream outputStream = new FileOutputStream(manifestFile)) {
 			manifest.write(outputStream);
 		}
-		finally {
-			outputStream.close();
-		}
 	}
 
 	private File getFilePath(String filename) {
@@ -97,13 +89,9 @@ public class TestJarFile {
 
 	private void copyToFile(InputStream inputStream, File file)
 			throws FileNotFoundException, IOException {
-		OutputStream outputStream = new FileOutputStream(file);
-		try {
+		try (OutputStream outputStream = new FileOutputStream(file)) {
 			copy(inputStream, outputStream);
 		}
-		finally {
-			outputStream.close();
-		}
 	}
 
 	private void copy(InputStream in, OutputStream out) throws IOException {