Filter non-jar artifacts when packaging libs in Gradle plugin

Previously, the Gradle plugin would package all of a project's
dependencies in the jar's lib directory, irrespective of each
dependency's type. This led to non-jar artifacts being packaged in
the lib directory where only jar dependencies are expected. See #334
for an example failure.

This commit updates the Gradle plugin such that it only packages
dependencies of type jar, ejb, ejb-client, test-jar, or bundle. This
brings the Gradle plugin into line with the Maven plugin.

Fixes #334.

spring-boot-tools/spring-boot-gradle-plugin/src/main/groovy/org/springframework/boot/gradle/task/ProjectLibraries.java

@@ -16,12 +16,15 @@
 
 package org.springframework.boot.gradle.task;
 
-import java.io.File;
 import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Set;
 
 import org.gradle.api.Project;
 import org.gradle.api.artifacts.Configuration;
-import org.gradle.api.file.FileCollection;
+import org.gradle.api.artifacts.ResolvedArtifact;
 import org.springframework.boot.loader.tools.Libraries;
 import org.springframework.boot.loader.tools.LibraryCallback;
 import org.springframework.boot.loader.tools.LibraryScope;
@@ -30,9 +33,14 @@ import org.springframework.boot.loader.tools.LibraryScope;
  * Expose Gradle {@link Configuration}s as {@link Libraries}.
  * 
  * @author Phillip Webb
+ * @author Andy Wilkinson
  */
 class ProjectLibraries implements Libraries {
 
+	private static final Set<String> SUPPORTED_TYPES = Collections
+			.unmodifiableSet(new HashSet<String>(Arrays.asList("jar", "ejb",
+					"ejb-client", "test-jar", "bundle")));
+
 	private final Project project;
 
 	private String providedConfigurationName = "providedRuntime";
@@ -64,41 +72,48 @@ class ProjectLibraries implements Libraries {
 	@Override
 	public void doWithLibraries(LibraryCallback callback) throws IOException {
 
-		FileCollection custom = this.customConfigurationName != null ? this.project
+		Configuration custom = this.customConfigurationName != null ? this.project
 				.getConfigurations().findByName(this.customConfigurationName) : null;
 
 		if (custom != null) {
-			libraries(LibraryScope.CUSTOM, custom, callback);
+			libraries(LibraryScope.CUSTOM, getResolvedArtifacts(custom), callback);
 		}
 		else {
-			FileCollection compile = this.project.getConfigurations()
-					.getByName("compile");
-
-			FileCollection runtime = this.project.getConfigurations()
-					.getByName("runtime");
-			runtime = runtime.minus(compile);
-
-			FileCollection provided = this.project.getConfigurations().findByName(
-					this.providedConfigurationName);
-			if (provided != null) {
-				compile = compile.minus(provided);
-				runtime = runtime.minus(provided);
-			}
+			Set<ResolvedArtifact> compileArtifacts = getResolvedArtifacts("compile");
+			Set<ResolvedArtifact> runtimeArtifacts = getResolvedArtifacts("runtime");
+			runtimeArtifacts.removeAll(compileArtifacts);
+
+			Set<ResolvedArtifact> providedArtifacts = getResolvedArtifacts(this.providedConfigurationName);
+			compileArtifacts.removeAll(providedArtifacts);
+			runtimeArtifacts.removeAll(providedArtifacts);
+
+			libraries(LibraryScope.COMPILE, compileArtifacts, callback);
+			libraries(LibraryScope.RUNTIME, runtimeArtifacts, callback);
+			libraries(LibraryScope.PROVIDED, providedArtifacts, callback);
+		}
+	}
 
-			libraries(LibraryScope.COMPILE, compile, callback);
-			libraries(LibraryScope.RUNTIME, runtime, callback);
-			libraries(LibraryScope.PROVIDED, provided, callback);
+	private Set<ResolvedArtifact> getResolvedArtifacts(Configuration configuration) {
+		if (configuration != null) {
+			return configuration.getResolvedConfiguration().getResolvedArtifacts();
+		}
+		else {
+			return Collections.emptySet();
 		}
+	}
 
+	private Set<ResolvedArtifact> getResolvedArtifacts(String configurationName) {
+		Configuration configuration = this.project.getConfigurations().findByName(
+				configurationName);
+		return getResolvedArtifacts(configuration);
 	}
 
-	private void libraries(LibraryScope scope, FileCollection files,
+	private void libraries(LibraryScope scope, Set<ResolvedArtifact> artifacts,
 			LibraryCallback callback) throws IOException {
-		if (files != null) {
-			for (File file : files) {
-				callback.library(file, scope);
+		for (ResolvedArtifact artifact : artifacts) {
+			if (SUPPORTED_TYPES.contains(artifact.getType())) {
+				callback.library(artifact.getFile(), scope);
 			}
 		}
 	}
-
 }