Polish "Support provided-scope libraries when extracting an executable war"

Make the extracted war runnable with java -jar: move root content
such as static files and JSPs to META-INF/resources/, name the
application jar *.jar, and write the META-INF/ directory entry
before the manifest.

Fail early when a library and a provided library share a file
name, as both would be extracted to the same location. Assert the
Spring-Boot-Lib-Provided attribute in the Maven and Gradle tests
and document war extraction.

See gh-51372

build-plugin/spring-boot-gradle-plugin/src/test/java/org/springframework/boot/gradle/tasks/bundling/AbstractBootArchiveTests.java

@@ -55,6 +55,7 @@ import org.gradle.api.internal.file.archive.ZipEntryConstants;
 import org.gradle.api.tasks.bundling.AbstractArchiveTask;
 import org.gradle.api.tasks.bundling.Jar;
 import org.gradle.internal.component.external.model.ModuleComponentArtifactIdentifier;
+import org.jspecify.annotations.Nullable;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
@@ -88,6 +89,8 @@ abstract class AbstractBootArchiveTests<T extends Jar & BootArchive> {
 
 	private final String libPath;
 
+	private final @Nullable String libProvidedPath;
+
 	private final String classesPath;
 
 	private final String indexPath;
@@ -96,11 +99,12 @@ abstract class AbstractBootArchiveTests<T extends Jar & BootArchive> {
 
 	private T task;
 
-	protected AbstractBootArchiveTests(Class<T> taskClass, String launcherClass, String libPath, String classesPath,
-			String indexPath) {
+	protected AbstractBootArchiveTests(Class<T> taskClass, String launcherClass, String libPath,
+			@Nullable String libProvidedPath, String classesPath, String indexPath) {
 		this.taskClass = taskClass;
 		this.launcherClass = launcherClass;
 		this.libPath = libPath;
+		this.libProvidedPath = libProvidedPath;
 		this.classesPath = classesPath;
 		this.indexPath = indexPath;
 	}
@@ -124,6 +128,8 @@ abstract class AbstractBootArchiveTests<T extends Jar & BootArchive> {
 			assertThat(jarFile.getManifest().getMainAttributes().getValue("Spring-Boot-Classes"))
 				.isEqualTo(this.classesPath);
 			assertThat(jarFile.getManifest().getMainAttributes().getValue("Spring-Boot-Lib")).isEqualTo(this.libPath);
+			assertThat(jarFile.getManifest().getMainAttributes().getValue("Spring-Boot-Lib-Provided"))
+				.isEqualTo(this.libProvidedPath);
 			assertThat(jarFile.getManifest().getMainAttributes().getValue("Spring-Boot-Version")).isNotNull();
 			assertThat(jarFile.getManifest().getMainAttributes().getValue("Implementation-Title"))
 				.isEqualTo(this.project.getName());

build-plugin/spring-boot-gradle-plugin/src/test/java/org/springframework/boot/gradle/tasks/bundling/BootJarTests.java

@@ -41,8 +41,8 @@ import static org.assertj.core.api.Assertions.assertThat;
 class BootJarTests extends AbstractBootArchiveTests<BootJar> {
 
 	BootJarTests() {
-		super(BootJar.class, "org.springframework.boot.loader.launch.JarLauncher", "BOOT-INF/lib/", "BOOT-INF/classes/",
-				"BOOT-INF/");
+		super(BootJar.class, "org.springframework.boot.loader.launch.JarLauncher", "BOOT-INF/lib/", null,
+				"BOOT-INF/classes/", "BOOT-INF/");
 	}
 
 	@BeforeEach

build-plugin/spring-boot-gradle-plugin/src/test/java/org/springframework/boot/gradle/tasks/bundling/BootWarTests.java

@@ -39,8 +39,8 @@ import static org.assertj.core.api.Assertions.assertThat;
 class BootWarTests extends AbstractBootArchiveTests<BootWar> {
 
 	BootWarTests() {
-		super(BootWar.class, "org.springframework.boot.loader.launch.WarLauncher", "WEB-INF/lib/", "WEB-INF/classes/",
-				"WEB-INF/");
+		super(BootWar.class, "org.springframework.boot.loader.launch.WarLauncher", "WEB-INF/lib/",
+				"WEB-INF/lib-provided/", "WEB-INF/classes/", "WEB-INF/");
 	}
 
 	@BeforeEach

documentation/spring-boot-docs/src/docs/antora/modules/reference/pages/packaging/efficient.adoc

@@ -33,6 +33,10 @@ $ java -jar my-app/my-app.jar
 
 After startup, you should not expect any differences in execution time between running an executable jar and running an extracted jar.
 
+NOTE: An executable war can be extracted in the same way.
+The result is a jar, for example `my-app/my-app.jar`, that is meant to be run with `java -jar`.
+Content from the root of the war, such as static files and JSPs from `src/main/webapp`, is moved to `META-INF/resources/` in the extracted jar.
+
 TIP: Run `java -Djarmode=tools -jar my-app.jar help extract` to see all possible options.
 
 

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

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2012-present 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.jarmode.tools;
+
+import java.io.File;
+import java.util.Locale;
+
+/**
+ * The type of archive that is being processed.
+ *
+ * @author Moritz Halbritter
+ */
+enum ArchiveType {
+
+	/**
+	 * A jar archive.
+	 */
+	JAR,
+
+	/**
+	 * A war archive.
+	 */
+	WAR;
+
+	private static final String WAR_EXTENSION = ".war";
+
+	static ArchiveType of(File file) {
+		return (file.getName().toLowerCase(Locale.ROOT).endsWith(WAR_EXTENSION)) ? WAR : JAR;
+	}
+
+}

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

@@ -87,7 +87,9 @@ class ExtractCommand extends Command {
 			"Name of the libraries directory. Only applicable when not using --launcher. Defaults to lib/");
 
 	private static final Option APPLICATION_FILENAME_OPTION = Option.of("application-filename", "string",
-			"Name of the application JAR file. Only applicable when not using --launcher. Defaults to the uber JAR filename");
+			"Name of the application JAR file. Only applicable when not using --launcher. Defaults to the uber JAR filename, with the extension replaced by .jar");
+
+	private static final String META_INF_DIRECTORY = "META-INF/";
 
 	private final Context context;
 
@@ -248,18 +250,25 @@ class ExtractCommand extends Command {
 		Manifest manifest = jarStructure.createLauncherManifest((library) -> librariesDirectory + library);
 		mkdirs(file.getParentFile());
 		try (JarOutputStream output = new JarOutputStream(new FileOutputStream(file))) {
+			Set<String> writtenEntries = new HashSet<>();
 			ManifestWriter manifestWriter = (sourceJarFile) -> {
 				JarEntry entry = createJarEntry(JarFile.MANIFEST_NAME,
 						sourceJarFile.getJarEntry(JarFile.MANIFEST_NAME));
+				output.putNextEntry(createJarEntry(META_INF_DIRECTORY, entry));
+				output.closeEntry();
+				writtenEntries.add(META_INF_DIRECTORY);
 				output.putNextEntry(entry);
 				manifest.write(new BufferedOutputStream(output));
 				output.closeEntry();
 			};
-			EnumSet<Type> allowedTypes = EnumSet.of(Type.APPLICATION_CLASS_OR_RESOURCE, Type.META_INF);
-			Set<String> writtenEntries = new HashSet<>();
+			EnumSet<Type> allowedTypes = EnumSet.of(Type.APPLICATION_CLASS_OR_RESOURCE, Type.META_INF,
+					Type.WEB_RESOURCE);
 			withJarEntries(this.context.getArchiveFile(), manifestWriter, ((stream, jarEntry) -> {
 				Entry entry = jarStructure.resolve(jarEntry);
 				if (entry != null && allowedTypes.contains(entry.type()) && StringUtils.hasLength(entry.location())) {
+					if (entry.type() == Type.WEB_RESOURCE) {
+						writeParentDirectories(output, writtenEntries, entry.location(), jarEntry);
+					}
 					JarEntry newJarEntry = createJarEntry(entry.location(), jarEntry);
 					if (writtenEntries.add(newJarEntry.getName())) {
 						output.putNextEntry(newJarEntry);
@@ -268,7 +277,7 @@ class ExtractCommand extends Command {
 					}
 					else {
 						if (!newJarEntry.isDirectory()) {
-							throw new IllegalStateException("Duplicate jar entry '%s' from original location '%s'"
+							throw new JarModeErrorException("Duplicate jar entry '%s' from original location '%s'"
 								.formatted(newJarEntry.getName(), entry.originalLocation()));
 						}
 					}
@@ -278,6 +287,19 @@ class ExtractCommand extends Command {
 		copyTimestamps(this.context.getArchiveFile(), file);
 	}
 
+	private void writeParentDirectories(JarOutputStream output, Set<String> writtenEntries, String location,
+			JarEntry originalEntry) throws IOException {
+		int index = location.indexOf('/');
+		while (index != -1 && index < location.length() - 1) {
+			String directory = location.substring(0, index + 1);
+			if (writtenEntries.add(directory)) {
+				output.putNextEntry(createJarEntry(directory, originalEntry));
+				output.closeEntry();
+			}
+			index = location.indexOf('/', index + 1);
+		}
+	}
+
 	private void copyTimestamps(File source, File destination) throws IOException {
 		BasicFileAttributes sourceAttributes = Files.getFileAttributeView(source.toPath(), BasicFileAttributeView.class)
 			.readAttributes();
@@ -291,7 +313,11 @@ class ExtractCommand extends Command {
 		if (value != null) {
 			return value;
 		}
-		return this.context.getArchiveFile().getName();
+		File archiveFile = this.context.getArchiveFile();
+		if (ArchiveType.of(archiveFile) == ArchiveType.WAR) {
+			return stripExtension(archiveFile.getName()) + ".jar";
+		}
+		return archiveFile.getName();
 	}
 
 	private static void extractEntry(InputStream stream, JarEntry entry, File file) throws IOException {

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

@@ -22,8 +22,10 @@ import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.NoSuchFileException;
 import java.util.Arrays;
+import java.util.HashMap;
 import java.util.LinkedHashSet;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 import java.util.function.UnaryOperator;
 import java.util.jar.Attributes;
@@ -31,11 +33,13 @@ import java.util.jar.Attributes.Name;
 import java.util.jar.JarFile;
 import java.util.jar.Manifest;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 import java.util.zip.ZipEntry;
 
 import org.jspecify.annotations.Nullable;
 
 import org.springframework.boot.jarmode.tools.JarStructure.Entry.Type;
+import org.springframework.boot.loader.jarmode.JarModeErrorException;
 import org.springframework.util.Assert;
 import org.springframework.util.StreamUtils;
 import org.springframework.util.StringUtils;
@@ -54,6 +58,10 @@ class IndexedJarStructure implements JarStructure {
 	private static final Set<String> ENTRY_IGNORE_LIST = Set.of("META-INF/", "META-INF/MANIFEST.MF",
 			"META-INF/services/java.nio.file.spi.FileSystemProvider");
 
+	private static final String LOADER_LOCATION = "org/springframework/boot/loader/";
+
+	private static final String WEB_RESOURCES_LOCATION = "META-INF/resources/";
+
 	private final Manifest originalManifest;
 
 	private final String libLocation;
@@ -64,12 +72,42 @@ class IndexedJarStructure implements JarStructure {
 
 	private final Set<String> classpathEntries;
 
-	IndexedJarStructure(Manifest originalManifest, String indexFile) {
+	private final Set<String> indexLocations;
+
+	private final ArchiveType archiveType;
+
+	IndexedJarStructure(Manifest originalManifest, String indexFile, ArchiveType archiveType) {
 		this.originalManifest = originalManifest;
 		this.libLocation = getLocation(originalManifest, "Spring-Boot-Lib");
 		this.providedLibLocation = getOptionalLocation(originalManifest, "Spring-Boot-Lib-Provided");
 		this.classesLocation = getLocation(originalManifest, "Spring-Boot-Classes");
 		this.classpathEntries = readIndexFile(indexFile);
+		this.indexLocations = getIndexLocations(originalManifest);
+		this.archiveType = archiveType;
+		checkForDuplicateLibraryNames();
+	}
+
+	private void checkForDuplicateLibraryNames() {
+		Map<String, String> libraries = new HashMap<>();
+		for (String classpathEntry : this.classpathEntries) {
+			String name = stripLibraryLocation(classpathEntry);
+			if (name == null) {
+				continue;
+			}
+			String existing = libraries.putIfAbsent(name, classpathEntry);
+			if (existing != null) {
+				throw new JarModeErrorException(
+						"Library name '%s' is used by both '%s' and '%s'".formatted(name, existing, classpathEntry));
+			}
+		}
+	}
+
+	private static Set<String> getIndexLocations(Manifest manifest) {
+		Attributes attributes = manifest.getMainAttributes();
+		return Stream
+			.of(attributes.getValue("Spring-Boot-Classpath-Index"), attributes.getValue("Spring-Boot-Layers-Index"))
+			.filter(StringUtils::hasLength)
+			.collect(Collectors.toSet());
 	}
 
 	private static String getLocation(Manifest manifest, String attribute) {
@@ -121,7 +159,24 @@ class IndexedJarStructure implements JarStructure {
 		if (name.startsWith("META-INF/")) {
 			return new Entry(name, name, Type.META_INF);
 		}
-		return null;
+		return resolveWebResource(name);
+	}
+
+	private @Nullable Entry resolveWebResource(String name) {
+		if (this.archiveType != ArchiveType.WAR || isWarPackagingEntry(name)) {
+			return null;
+		}
+		return new Entry(name, WEB_RESOURCES_LOCATION + name, Type.WEB_RESOURCE);
+	}
+
+	private boolean isWarPackagingEntry(String name) {
+		if (this.indexLocations.contains(name) || name.startsWith(this.libLocation)) {
+			return true;
+		}
+		if (this.providedLibLocation != null && name.startsWith(this.providedLibLocation)) {
+			return true;
+		}
+		return name.endsWith("/") && LOADER_LOCATION.startsWith(name);
 	}
 
 	@Override
@@ -141,13 +196,19 @@ class IndexedJarStructure implements JarStructure {
 	}
 
 	private String toStructureDependency(String libEntryName) {
+		String name = stripLibraryLocation(libEntryName);
+		Assert.state(name != null, () -> "Invalid library location " + libEntryName);
+		return name;
+	}
+
+	private @Nullable String stripLibraryLocation(String libEntryName) {
 		if (libEntryName.startsWith(this.libLocation)) {
 			return libEntryName.substring(this.libLocation.length());
 		}
 		if (this.providedLibLocation != null && libEntryName.startsWith(this.providedLibLocation)) {
 			return libEntryName.substring(this.providedLibLocation.length());
 		}
-		throw new IllegalStateException("Invalid library location " + libEntryName);
+		return null;
 	}
 
 	private static String getMandatoryAttribute(Manifest manifest, String attribute) {
@@ -164,7 +225,7 @@ class IndexedJarStructure implements JarStructure {
 				ZipEntry entry = jarFile.getEntry(location);
 				if (entry != null) {
 					String indexFile = StreamUtils.copyToString(jarFile.getInputStream(entry), StandardCharsets.UTF_8);
-					return new IndexedJarStructure(manifest, indexFile);
+					return new IndexedJarStructure(manifest, indexFile, ArchiveType.of(file));
 				}
 			}
 			return null;

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

@@ -73,7 +73,7 @@ interface JarStructure {
 
 		enum Type {
 
-			LIBRARY, APPLICATION_CLASS_OR_RESOURCE, LOADER, META_INF
+			LIBRARY, APPLICATION_CLASS_OR_RESOURCE, LOADER, META_INF, WEB_RESOURCE
 
 		}
 

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

@@ -79,8 +79,14 @@ abstract class AbstractJarModeTests {
 
 	File createArchive(Manifest manifest, @Nullable Instant creationTime, @Nullable Instant lastModifiedTime,
 			@Nullable Instant lastAccessTime, String... entries) throws IOException {
+		return createArchive("test.jar", manifest, creationTime, lastModifiedTime, lastAccessTime, entries);
+	}
+
+	File createArchive(String filename, Manifest manifest, @Nullable Instant creationTime,
+			@Nullable Instant lastModifiedTime, @Nullable Instant lastAccessTime, String... entries)
+			throws IOException {
 		Assert.state(entries.length % 2 == 0, "Entries must be key value pairs");
-		File file = new File(this.tempDir, "test.jar");
+		File file = new File(this.tempDir, filename);
 		try (JarOutputStream jar = new JarOutputStream(new FileOutputStream(file))) {
 			ZipEntry manifestEntry = createEntry(JarFile.MANIFEST_NAME, creationTime, lastModifiedTime, lastAccessTime);
 			jar.putNextEntry(manifestEntry);

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

@@ -136,6 +136,12 @@ class ExtractCommandTests extends AbstractJarModeTests {
 						"Spring-Boot-Classpath-Index", "Spring-Boot-Layers-Index");
 		}
 
+		@Test
+		void shouldWriteMetaInfDirectoryBeforeManifest() throws IOException {
+			run(ExtractCommandTests.this.archive);
+			assertThat(getJarEntryNames(file("test/test.jar"))).startsWith("META-INF/", "META-INF/MANIFEST.MF");
+		}
+
 		@Test
 		void applicationContainsApplicationClassesAndResources() throws IOException {
 			run(ExtractCommandTests.this.archive);
@@ -260,7 +266,8 @@ class ExtractCommandTests extends AbstractJarModeTests {
 			run(file);
 			File application = file("test/test.jar");
 			List<String> entryNames = getJarEntryNames(application);
-			assertThat(entryNames).containsExactlyInAnyOrder("META-INF/native-image/", "META-INF/MANIFEST.MF");
+			assertThat(entryNames).containsExactlyInAnyOrder("META-INF/", "META-INF/native-image/",
+					"META-INF/MANIFEST.MF");
 		}
 
 		@Test
@@ -269,13 +276,86 @@ class ExtractCommandTests extends AbstractJarModeTests {
 					"/jar-contents/classpath.idx", "META-INF/native-image/native-image.properties",
 					"/jar-contents/empty-file", "BOOT-INF/classes/META-INF/native-image/native-image.properties",
 					"/jar-contents/empty-file");
-			assertThatIllegalStateException().isThrownBy(() -> run(file))
+			assertThatExceptionOfType(JarModeErrorException.class).isThrownBy(() -> run(file))
 				.withMessage(
 						"Duplicate jar entry 'META-INF/native-image/native-image.properties' from original location 'BOOT-INF/classes/META-INF/native-image/native-image.properties'");
 		}
 
 	}
 
+	@Nested
+	class ExtractWar {
+
+		private Manifest manifest;
+
+		private File war;
+
+		@BeforeEach
+		void setUp() throws IOException {
+			this.manifest = createManifest("Spring-Boot-Classpath-Index: WEB-INF/classpath.idx",
+					"Spring-Boot-Lib: WEB-INF/lib/", "Spring-Boot-Lib-Provided: WEB-INF/lib-provided/",
+					"Spring-Boot-Classes: WEB-INF/classes/", "Start-Class: org.example.Main",
+					"Spring-Boot-Layers-Index: WEB-INF/layers.idx");
+			this.war = createArchive("test.war", this.manifest, null, null, null, "WEB-INF/classpath.idx",
+					"/jar-contents/war-classpath.idx", "WEB-INF/layers.idx", "/jar-contents/war-layers.idx",
+					"WEB-INF/lib/dependency-1.jar", "/jar-contents/dependency-1",
+					"WEB-INF/lib-provided/dependency-2.jar", "/jar-contents/dependency-2",
+					"org/springframework/boot/loader/launch/WarLauncher.class", "/jar-contents/JarLauncher",
+					"WEB-INF/classes/application.properties", "/jar-contents/application.properties", "index.html",
+					"/jar-contents/empty-file", "WEB-INF/jsp/", "/jar-contents/empty-file", "WEB-INF/jsp/hello.jsp",
+					"/jar-contents/empty-file");
+		}
+
+		@Test
+		void shouldCreateApplicationJar() throws IOException {
+			run(this.war);
+			assertThat(listFilenames())
+				.contains("test/test.jar", "test/lib/dependency-1.jar", "test/lib/dependency-2.jar")
+				.doesNotContain("test/test.war");
+		}
+
+		@Test
+		void shouldMoveWebResourcesToMetaInfResources() throws IOException {
+			run(this.war);
+			assertThat(getJarEntryNames(file("test/test.jar"))).containsExactlyInAnyOrder("META-INF/MANIFEST.MF",
+					"application.properties", "META-INF/", "META-INF/resources/", "META-INF/resources/index.html",
+					"META-INF/resources/WEB-INF/", "META-INF/resources/WEB-INF/jsp/",
+					"META-INF/resources/WEB-INF/jsp/hello.jsp");
+		}
+
+		@Test
+		void shouldMoveWebResourcesToMetaInfResourcesWhenUsingLayers() throws IOException {
+			run(this.war, "--layers");
+			assertThat(listFilenames()).contains("test/dependencies/lib/dependency-1.jar",
+					"test/dependencies/lib/dependency-2.jar");
+			assertThat(getJarEntryNames(file("test/application/test.jar"))).contains("META-INF/resources/index.html",
+					"META-INF/resources/WEB-INF/jsp/hello.jsp");
+		}
+
+		@Test
+		void shouldFailWhenWebResourceCollidesWithClassesResource() throws IOException {
+			File war = createArchive("test.war", this.manifest, null, null, null, "WEB-INF/classpath.idx",
+					"/jar-contents/war-classpath.idx", "WEB-INF/lib/dependency-1.jar", "/jar-contents/dependency-1",
+					"index.html", "/jar-contents/empty-file", "WEB-INF/classes/META-INF/resources/index.html",
+					"/jar-contents/empty-file");
+			assertThatExceptionOfType(JarModeErrorException.class).isThrownBy(() -> run(war))
+				.withMessage("Duplicate jar entry 'META-INF/resources/index.html' from original location "
+						+ "'WEB-INF/classes/META-INF/resources/index.html'");
+		}
+
+		@Test
+		void shouldFailWhenLibraryAndProvidedLibraryHaveSameName() throws IOException {
+			File war = createArchive("test.war", this.manifest, null, null, null, "WEB-INF/classpath.idx",
+					"/jar-contents/war-duplicate-classpath.idx", "WEB-INF/lib/dependency-1.jar",
+					"/jar-contents/dependency-1", "WEB-INF/lib-provided/dependency-1.jar",
+					"/jar-contents/dependency-1");
+			assertThatExceptionOfType(JarModeErrorException.class).isThrownBy(() -> run(war))
+				.withMessage("Library name 'dependency-1.jar' is used by both 'WEB-INF/lib/dependency-1.jar' and "
+						+ "'WEB-INF/lib-provided/dependency-1.jar'");
+		}
+
+	}
+
 	@Nested
 	class ExtractWithLayers {
 

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

@@ -33,9 +33,10 @@ import org.junit.jupiter.api.io.TempDir;
 
 import org.springframework.boot.jarmode.tools.JarStructure.Entry;
 import org.springframework.boot.jarmode.tools.JarStructure.Entry.Type;
+import org.springframework.boot.loader.jarmode.JarModeErrorException;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 /**
  * Tests for {@link IndexedJarStructure}.
@@ -44,6 +45,23 @@ import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
  */
 class IndexedJarStructureTests {
 
+	private static final String WAR_MANIFEST = """
+			Manifest-Version: 1.0
+			Main-Class: org.springframework.boot.loader.launch.WarLauncher
+			Start-Class: org.springframework.boot.jarmode.tools.IndexedJarStructureTests
+			Spring-Boot-Version: 3.3.0-SNAPSHOT
+			Spring-Boot-Classes: WEB-INF/classes/
+			Spring-Boot-Lib: WEB-INF/lib/
+			Spring-Boot-Lib-Provided: WEB-INF/lib-provided/
+			Spring-Boot-Classpath-Index: WEB-INF/classpath.idx
+			Spring-Boot-Layers-Index: WEB-INF/layers.idx
+			""";
+
+	private static final String WAR_INDEX_FILE = """
+			- "WEB-INF/lib/spring-webmvc-6.1.4.jar"
+			- "WEB-INF/lib-provided/tomcat-embed-core-10.1.19.jar"
+			""";
+
 	@Test
 	void shouldResolveLibraryEntry() throws IOException {
 		IndexedJarStructure structure = createStructure();
@@ -68,8 +86,42 @@ class IndexedJarStructureTests {
 	void shouldCreateLauncherManifestForWarWithProvidedLibraries() throws IOException {
 		IndexedJarStructure structure = createWarStructure();
 		Manifest manifest = structure.createLauncherManifest(UnaryOperator.identity());
-		assertThat(getAttributes(manifest)).containsEntry("Class-Path",
-				"spring-webmvc-6.1.4.jar tomcat-embed-core-10.1.19.jar");
+		assertThat(getAttributes(manifest))
+			.containsEntry("Class-Path", "spring-webmvc-6.1.4.jar tomcat-embed-core-10.1.19.jar")
+			.doesNotContainKey("Spring-Boot-Lib-Provided");
+	}
+
+	@Test
+	void shouldResolveWarRootEntryAsWebResource() throws IOException {
+		IndexedJarStructure structure = createWarStructure();
+		Entry entry = structure.resolve("WEB-INF/jsp/hello.jsp");
+		assertThat(entry).isNotNull();
+		assertThat(entry.location()).isEqualTo("META-INF/resources/WEB-INF/jsp/hello.jsp");
+		assertThat(entry.originalLocation()).isEqualTo("WEB-INF/jsp/hello.jsp");
+		assertThat(entry.type()).isEqualTo(Type.WEB_RESOURCE);
+	}
+
+	@Test
+	void shouldNotResolveWarIndexFilesAsWebResources() throws IOException {
+		IndexedJarStructure structure = createWarStructure();
+		assertThat(structure.resolve("WEB-INF/classpath.idx")).isNull();
+		assertThat(structure.resolve("WEB-INF/layers.idx")).isNull();
+	}
+
+	@Test
+	void shouldNotResolveWarLibraryOrLoaderDirectoriesAsWebResources() throws IOException {
+		IndexedJarStructure structure = createWarStructure();
+		assertThat(structure.resolve("WEB-INF/lib/")).isNull();
+		assertThat(structure.resolve("WEB-INF/lib/doesnt-exist.jar")).isNull();
+		assertThat(structure.resolve("WEB-INF/lib-provided/")).isNull();
+		assertThat(structure.resolve("org/")).isNull();
+		assertThat(structure.resolve("org/springframework/boot/")).isNull();
+	}
+
+	@Test
+	void shouldNotResolveJarRootEntry() throws IOException {
+		IndexedJarStructure structure = createStructure();
+		assertThat(structure.resolve("index.html")).isNull();
 	}
 
 	@Test
@@ -132,66 +184,34 @@ class IndexedJarStructureTests {
 			.isEqualTo(Type.APPLICATION_CLASS_OR_RESOURCE);
 	}
 
+	@Test
+	void shouldFailWhenLibraryAndProvidedLibraryHaveSameName() {
+		String indexFile = """
+				- "WEB-INF/lib/utils-1.0.jar"
+				- "WEB-INF/lib-provided/utils-1.0.jar"
+				""";
+		assertThatExceptionOfType(JarModeErrorException.class).isThrownBy(() -> createWarStructure(indexFile))
+			.withMessage("Library name 'utils-1.0.jar' is used by both 'WEB-INF/lib/utils-1.0.jar' and "
+					+ "'WEB-INF/lib-provided/utils-1.0.jar'");
+	}
+
 	private Map<String, String> getAttributes(Manifest manifest) {
 		Map<String, String> result = new HashMap<>();
 		manifest.getMainAttributes().forEach((key, value) -> result.put(key.toString(), value.toString()));
 		return result;
 	}
 
-	@Test
-	void shouldFailToResolveProvidedLibraryWhenAttributeIsMissing() throws IOException {
-		// an archive whose index references lib-provided but whose manifest does not
-		// record the location has nothing to flatten the entry against
-		IndexedJarStructure structure = createWarStructureWithoutProvidedLibAttribute();
-		assertThatIllegalStateException()
-			.isThrownBy(() -> structure.resolve("WEB-INF/lib-provided/tomcat-embed-core-10.1.19.jar"))
-			.withMessageContaining("Invalid library location");
-	}
-
-	@Test
-	void launcherManifestShouldNotContainProvidedLibAttribute() throws IOException {
-		IndexedJarStructure structure = createWarStructure();
-		Manifest manifest = structure.createLauncherManifest(UnaryOperator.identity());
-		assertThat(getAttributes(manifest)).doesNotContainKey("Spring-Boot-Lib-Provided");
-	}
-
 	private IndexedJarStructure createStructure() throws IOException {
-		return new IndexedJarStructure(createManifest(), createIndexFile());
+		return new IndexedJarStructure(createManifest(), createIndexFile(), ArchiveType.JAR);
 	}
 
 	private IndexedJarStructure createWarStructure() throws IOException {
-		Manifest manifest = new Manifest(new ByteArrayInputStream("""
-				Manifest-Version: 1.0
-				Main-Class: org.springframework.boot.loader.launch.WarLauncher
-				Start-Class: org.springframework.boot.jarmode.tools.IndexedJarStructureTests
-				Spring-Boot-Version: 3.3.0-SNAPSHOT
-				Spring-Boot-Classes: WEB-INF/classes/
-				Spring-Boot-Lib: WEB-INF/lib/
-				Spring-Boot-Lib-Provided: WEB-INF/lib-provided/
-				Spring-Boot-Classpath-Index: WEB-INF/classpath.idx
-				""".getBytes(StandardCharsets.UTF_8)));
-		String indexFile = """
-				- "WEB-INF/lib/spring-webmvc-6.1.4.jar"
-				- "WEB-INF/lib-provided/tomcat-embed-core-10.1.19.jar"
-				""";
-		return new IndexedJarStructure(manifest, indexFile);
+		return createWarStructure(WAR_INDEX_FILE);
 	}
 
-	private IndexedJarStructure createWarStructureWithoutProvidedLibAttribute() throws IOException {
-		Manifest manifest = new Manifest(new ByteArrayInputStream("""
-				Manifest-Version: 1.0
-				Main-Class: org.springframework.boot.loader.launch.WarLauncher
-				Start-Class: org.springframework.boot.jarmode.tools.IndexedJarStructureTests
-				Spring-Boot-Version: 3.3.0-SNAPSHOT
-				Spring-Boot-Classes: WEB-INF/classes/
-				Spring-Boot-Lib: WEB-INF/lib/
-				Spring-Boot-Classpath-Index: WEB-INF/classpath.idx
-				""".getBytes(StandardCharsets.UTF_8)));
-		String indexFile = """
-				- "WEB-INF/lib/spring-webmvc-6.1.4.jar"
-				- "WEB-INF/lib-provided/tomcat-embed-core-10.1.19.jar"
-				""";
-		return new IndexedJarStructure(manifest, indexFile);
+	private IndexedJarStructure createWarStructure(String indexFile) throws IOException {
+		Manifest manifest = new Manifest(new ByteArrayInputStream(WAR_MANIFEST.getBytes(StandardCharsets.UTF_8)));
+		return new IndexedJarStructure(manifest, indexFile, ArchiveType.WAR);
 	}
 
 	private String createIndexFile() {

loader/spring-boot-jarmode-tools/src/test/resources/jar-contents/war-classpath.idx

@@ -0,0 +1,2 @@
+- "WEB-INF/lib/dependency-1.jar"
+- "WEB-INF/lib-provided/dependency-2.jar"

loader/spring-boot-jarmode-tools/src/test/resources/jar-contents/war-duplicate-classpath.idx

@@ -0,0 +1,2 @@
+- "WEB-INF/lib/dependency-1.jar"
+- "WEB-INF/lib-provided/dependency-1.jar"

loader/spring-boot-jarmode-tools/src/test/resources/jar-contents/war-layers.idx

@@ -0,0 +1,12 @@
+- "dependencies":
+  - "WEB-INF/lib/dependency-1.jar"
+  - "WEB-INF/lib-provided/"
+- "spring-boot-loader":
+  - "org/"
+- "application":
+  - "META-INF/"
+  - "WEB-INF/classes/"
+  - "WEB-INF/classpath.idx"
+  - "WEB-INF/jsp/"
+  - "WEB-INF/layers.idx"
+  - "index.html"

loader/spring-boot-jarmode-tools/src/test/resources/org/springframework/boot/jarmode/tools/tools-error-option-missing-value-output.txt

@@ -10,5 +10,5 @@ Options:
   --layers string list           Layers to extract
   --destination string           Directory to extract files to. Defaults to a directory named after the uber JAR (without the file extension)
   --libraries string             Name of the libraries directory. Only applicable when not using --launcher. Defaults to lib/
-  --application-filename string  Name of the application JAR file. Only applicable when not using --launcher. Defaults to the uber JAR filename
+  --application-filename string  Name of the application JAR file. Only applicable when not using --launcher. Defaults to the uber JAR filename, with the extension replaced by .jar
   --force                        Whether to ignore non-empty directories, extract anyway

loader/spring-boot-jarmode-tools/src/test/resources/org/springframework/boot/jarmode/tools/tools-error-option-unknown-output.txt

@@ -10,5 +10,5 @@ Options:
   --layers string list           Layers to extract
   --destination string           Directory to extract files to. Defaults to a directory named after the uber JAR (without the file extension)
   --libraries string             Name of the libraries directory. Only applicable when not using --launcher. Defaults to lib/
-  --application-filename string  Name of the application JAR file. Only applicable when not using --launcher. Defaults to the uber JAR filename
+  --application-filename string  Name of the application JAR file. Only applicable when not using --launcher. Defaults to the uber JAR filename, with the extension replaced by .jar
   --force                        Whether to ignore non-empty directories, extract anyway

loader/spring-boot-jarmode-tools/src/test/resources/org/springframework/boot/jarmode/tools/tools-help-extract-output.txt

@@ -8,5 +8,5 @@ Options:
   --layers string list           Layers to extract
   --destination string           Directory to extract files to. Defaults to a directory named after the uber JAR (without the file extension)
   --libraries string             Name of the libraries directory. Only applicable when not using --launcher. Defaults to lib/
-  --application-filename string  Name of the application JAR file. Only applicable when not using --launcher. Defaults to the uber JAR filename
+  --application-filename string  Name of the application JAR file. Only applicable when not using --launcher. Defaults to the uber JAR filename, with the extension replaced by .jar
   --force                        Whether to ignore non-empty directories, extract anyway

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

@@ -416,9 +416,9 @@ public abstract class Packager {
 		else {
 			attributes.putValue(BOOT_CLASSES_ATTRIBUTE, layout.getClassesLocation());
 		}
-		String libraryLocation = getLayout().getLibraryLocation("", LibraryScope.COMPILE);
+		String libraryLocation = layout.getLibraryLocation("", LibraryScope.COMPILE);
 		putIfHasLength(attributes, BOOT_LIB_ATTRIBUTE, libraryLocation);
-		String providedLibraryLocation = getLayout().getLibraryLocation("", LibraryScope.PROVIDED);
+		String providedLibraryLocation = layout.getLibraryLocation("", LibraryScope.PROVIDED);
 		if (!ObjectUtils.nullSafeEquals(providedLibraryLocation, libraryLocation)) {
 			putIfHasLength(attributes, BOOT_LIB_PROVIDED_ATTRIBUTE, providedLibraryLocation);
 		}

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

@@ -396,6 +396,8 @@ abstract class AbstractPackagerTests<P extends Packager> {
 		assertThat(actualManifest).isNotNull();
 		assertThat(actualManifest.getMainAttributes()).containsEntry(new Attributes.Name("Spring-Boot-Lib"),
 				"BOOT-INF/lib/");
+		assertThat(actualManifest.getMainAttributes())
+			.doesNotContainKey(new Attributes.Name("Spring-Boot-Lib-Provided"));
 		assertThat(actualManifest.getMainAttributes()).containsEntry(new Attributes.Name("Spring-Boot-Classes"),
 				"BOOT-INF/classes/");
 	}
@@ -409,6 +411,8 @@ abstract class AbstractPackagerTests<P extends Packager> {
 		assertThat(actualManifest).isNotNull();
 		assertThat(actualManifest.getMainAttributes()).containsEntry(new Attributes.Name("Spring-Boot-Lib"),
 				"WEB-INF/lib/");
+		assertThat(actualManifest.getMainAttributes()).containsEntry(new Attributes.Name("Spring-Boot-Lib-Provided"),
+				"WEB-INF/lib-provided/");
 		assertThat(actualManifest.getMainAttributes()).containsEntry(new Attributes.Name("Spring-Boot-Classes"),
 				"WEB-INF/classes/");
 	}