Use lambdas when possible

Replace anonymous inner classes with lambda declarations (when possible
using method references).

See gh-9781

spring-boot-cli/src/main/java/org/springframework/boot/cli/command/archive/ArchiveCommand.java

@@ -57,9 +57,7 @@ import org.springframework.boot.cli.compiler.RepositoryConfigurationFactory;
 import org.springframework.boot.cli.compiler.grape.RepositoryConfiguration;
 import org.springframework.boot.loader.tools.JarWriter;
 import org.springframework.boot.loader.tools.Layout;
-import org.springframework.boot.loader.tools.Libraries;
 import org.springframework.boot.loader.tools.Library;
-import org.springframework.boot.loader.tools.LibraryCallback;
 import org.springframework.boot.loader.tools.LibraryScope;
 import org.springframework.boot.loader.tools.Repackager;
 import org.springframework.core.io.Resource;
@@ -198,13 +196,9 @@ abstract class ArchiveCommand extends OptionParsingCommand {
 			libraries.addAll(createLibraries(dependencies));
 			Repackager repackager = new Repackager(file);
 			repackager.setMainClass(PackagedSpringApplicationLauncher.class.getName());
-			repackager.repackage(new Libraries() {
-
-				@Override
-				public void doWithLibraries(LibraryCallback callback) throws IOException {
-					for (Library library : libraries) {
-						callback.library(library);
-					}
+			repackager.repackage((callback) -> {
+				for (Library library : libraries) {
+					callback.library(library);
 				}
 			});
 		}

spring-boot-cli/src/main/java/org/springframework/boot/cli/command/init/ServiceCapabilitiesReportGenerator.java

@@ -94,11 +94,7 @@ class ServiceCapabilitiesReportGenerator {
 
 	private List<Dependency> getSortedDependencies(InitializrServiceMetadata metadata) {
 		ArrayList<Dependency> dependencies = new ArrayList<>(metadata.getDependencies());
-		dependencies.sort(new Comparator<Dependency>() {
-			@Override public int compare(Dependency o1, Dependency o2) {
-				return o1.getId().compareTo(o2.getId());
-			}
-		});
+		dependencies.sort(Comparator.comparing(Dependency::getId));
 		return dependencies;
 	}
 
@@ -107,15 +103,7 @@ class ServiceCapabilitiesReportGenerator {
 		report.append("Available project types:" + NEW_LINE);
 		report.append("------------------------" + NEW_LINE);
 		SortedSet<Entry<String, ProjectType>> entries = new TreeSet<>(
-				new Comparator<Entry<String, ProjectType>>() {
-
-					@Override
-					public int compare(Entry<String, ProjectType> o1,
-							Entry<String, ProjectType> o2) {
-						return o1.getKey().compareTo(o2.getKey());
-					}
-
-				});
+				Comparator.comparing(Entry::getKey));
 		entries.addAll(metadata.getProjectTypes().entrySet());
 		for (Entry<String, ProjectType> entry : entries) {
 			ProjectType type = entry.getValue();

spring-boot-cli/src/main/java/org/springframework/boot/cli/command/options/OptionHandler.java

@@ -130,17 +130,10 @@ public class OptionHandler {
 
 		@Override
 		public String format(Map<String, ? extends OptionDescriptor> options) {
-			Comparator<OptionDescriptor> comparator = new Comparator<OptionDescriptor>() {
-				@Override
-				public int compare(OptionDescriptor first, OptionDescriptor second) {
-					return first.options().iterator().next()
-							.compareTo(second.options().iterator().next());
-				}
-			};
-
+			Comparator<OptionDescriptor> comparator = (first, second) -> first.options()
+					.iterator().next().compareTo(second.options().iterator().next());
 			Set<OptionDescriptor> sorted = new TreeSet<>(comparator);
 			sorted.addAll(options.values());
-
 			for (OptionDescriptor descriptor : sorted) {
 				if (!descriptor.representsNonOptions()) {
 					this.help.add(new OptionHelpAdapter(descriptor));

spring-boot-cli/src/main/java/org/springframework/boot/cli/command/shell/Shell.java

@@ -119,12 +119,7 @@ public class Shell {
 	}
 
 	private void attachSignalHandler() {
-		SignalUtils.attachSignalHandler(new Runnable() {
-			@Override
-			public void run() {
-				handleSigInt();
-			}
-		});
+		SignalUtils.attachSignalHandler(this::handleSigInt);
 	}
 
 	/**

spring-boot-cli/src/main/java/org/springframework/boot/cli/compiler/ExtendedGroovyClassLoader.java

@@ -122,23 +122,23 @@ public class ExtendedGroovyClassLoader extends GroovyClassLoader {
 
 	@Override
 	public ClassCollector createCollector(CompilationUnit unit, SourceUnit su) {
-		InnerLoader loader = AccessController
-				.doPrivileged(new PrivilegedAction<InnerLoader>() {
-					@Override
-					public InnerLoader run() {
-						return new InnerLoader(ExtendedGroovyClassLoader.this) {
-							// Don't return URLs from the inner loader so that Tomcat only
-							// searches the parent. Fixes 'TLD skipped' issues
-							@Override
-							public URL[] getURLs() {
-								return NO_URLS;
-							}
-						};
-					}
-				});
+		InnerLoader loader = AccessController.doPrivileged(getInnerLoader());
 		return new ExtendedClassCollector(loader, unit, su);
 	}
 
+	private PrivilegedAction<InnerLoader> getInnerLoader() {
+		return () -> new InnerLoader(ExtendedGroovyClassLoader.this) {
+
+			// Don't return URLs from the inner loader so that Tomcat only
+			// searches the parent. Fixes 'TLD skipped' issues
+			@Override
+			public URL[] getURLs() {
+				return NO_URLS;
+			}
+
+		};
+	}
+
 	public CompilerConfiguration getConfiguration() {
 		return this.configuration;
 	}

spring-boot-cli/src/main/java/org/springframework/boot/cli/compiler/grape/AetherGrapeEngine.java

@@ -100,19 +100,11 @@ public class AetherGrapeEngine implements GrapeEngine {
 				|| Boolean.getBoolean("groovy.grape.report.downloads")) {
 			return new DetailedProgressReporter(session, System.out);
 		}
-		else if ("none".equals(progressReporter)) {
-			return new ProgressReporter() {
-
-				@Override
-				public void finished() {
-
-				}
-
+		if ("none".equals(progressReporter)) {
+			return () -> {
 			};
 		}
-		else {
-			return new SummaryProgressReporter(session, System.out);
-		}
+		return new SummaryProgressReporter(session, System.out);
 	}
 
 	@Override