Enhanced IBuildSupport usage to support other build tools such as bazel

org.eclipse.jdt.ls.core/src/org/eclipse/jdt/ls/core/internal/ExtensionsExtractor.java

@@ -0,0 +1,54 @@
+/*******************************************************************************
+ * Copyright (c) 2021 Red Hat Inc. and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-2.0
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Red Hat Inc. - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.jdt.ls.core.internal;
+
+import java.util.List;
+import java.util.Map;
+import java.util.TreeMap;
+import java.util.stream.Collectors;
+
+import org.eclipse.core.runtime.IConfigurationElement;
+import org.eclipse.core.runtime.Platform;
+
+/**
+ * The class simplifies extracting extensions from the extension points.
+ *
+ * @author D.Bushenko
+ *
+ */
+public class ExtensionsExtractor {
+	public static <T> List<T> extractOrderedExtensions(final String namespace, final String extensionPointName) {
+
+		final var extensionPoint = Platform.getExtensionRegistry().getExtensionPoint(namespace, extensionPointName);
+		final var configs = extensionPoint.getConfigurationElements();
+
+		Map<Integer, T> extensionMap = new TreeMap<>();
+
+		for (int i = 0; i < configs.length; i++) {
+				Integer order = Integer.valueOf(configs[i].getAttribute("order"));
+				extensionMap.put(order, makeExtension(configs[i]));
+		}
+		return extensionMap.values().stream().collect(Collectors.toUnmodifiableList());
+	}
+
+	@SuppressWarnings("unchecked")
+	private static <T> T makeExtension(IConfigurationElement config) {
+		try {
+			return (T) config.createExecutableExtension("class");
+
+		} catch (Exception ex) {
+			throw new IllegalArgumentException("Could not create the extension", ex);
+		}
+	}
+
+}

org.eclipse.jdt.ls.core/src/org/eclipse/jdt/ls/core/internal/ProjectUtils.java

@@ -23,6 +23,7 @@
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Optional;
 import java.util.Set;
 import java.util.stream.Collectors;
@@ -48,6 +49,9 @@
 import org.eclipse.jdt.core.IJavaProject;
 import org.eclipse.jdt.core.JavaCore;
 import org.eclipse.jdt.core.JavaModelException;
+import org.eclipse.jdt.ls.core.internal.managers.BuildSupportManager;
+import org.eclipse.jdt.ls.core.internal.managers.IBuildSupport;
+import org.eclipse.jdt.ls.core.internal.managers.InternalBuildSupports;
 import org.eclipse.jdt.ls.core.internal.managers.ProjectsManager;
 import org.eclipse.jdt.ls.core.internal.preferences.PreferenceManager;
 import org.eclipse.m2e.core.internal.IMavenConstants;
@@ -91,7 +95,12 @@ public static boolean isGradleProject(IProject project) {
 	}
 
 	public static boolean isGeneralJavaProject(IProject project) {
-		return isJavaProject(project) && !isMavenProject(project) && !isGradleProject(project);
+		return isJavaProject(project) && isInternalBuildSupport(BuildSupportManager.find(project).orElse(null));
+	}
+
+	public static boolean isInternalBuildSupport(IBuildSupport buildSupport) {
+		return buildSupport != null && Arrays.stream(InternalBuildSupports.values())
+				.anyMatch(bsn -> Objects.equals(buildSupport.buildToolName(), bsn.toString()));
 	}
 
 	public static String getJavaSourceLevel(IProject project) {

org.eclipse.jdt.ls.core/src/org/eclipse/jdt/ls/core/internal/commands/BuildPathCommand.java

@@ -34,19 +34,24 @@
 import org.eclipse.jdt.ls.core.internal.Messages;
 import org.eclipse.jdt.ls.core.internal.ProjectUtils;
 import org.eclipse.jdt.ls.core.internal.ResourceUtils;
+import org.eclipse.jdt.ls.core.internal.managers.BuildSupportManager;
+import org.eclipse.jdt.ls.core.internal.managers.IBuildSupport;
 import org.eclipse.jdt.ls.core.internal.managers.ProjectsManager;
 import org.eclipse.jdt.ls.core.internal.preferences.PreferenceManager;
 
 public class BuildPathCommand {
-	public static final String UNSUPPORTED_ON_MAVEN = "Unsupported operation. Please use pom.xml file to manage the source directories of maven project.";
-	public static final String UNSUPPORTED_ON_GRADLE = "Unsupported operation. Please use build.gradle file to manage the source directories of gradle project.";
+	private static final String UNSUPPORTED_OPERATION = "Unsupported operation. Please use your build tool project file to manage the source directories of the project.";
+
+	private static String unsupportedOperationMessage(IProject targetProject) {
+		return BuildSupportManager.obtainBuildSupports().stream().filter(bs -> bs.applies(targetProject)).findFirst().map(IBuildSupport::unsupportedOperationMessage).orElse(UNSUPPORTED_OPERATION);
+	}
 
 	public static Result addToSourcePath(String sourceFolderUri) {
 		IPath sourceFolderPath = ResourceUtils.filePathFromURI(sourceFolderUri);
 		IProject targetProject = findBelongedProject(sourceFolderPath);
+
 		if (targetProject != null && !ProjectUtils.isGeneralJavaProject(targetProject)) {
-			String message = ProjectUtils.isGradleProject(targetProject) ? UNSUPPORTED_ON_GRADLE : UNSUPPORTED_ON_MAVEN;
-			return new Result(false, message);
+			return new Result(false, unsupportedOperationMessage(targetProject));
 		}
 
 		IPath projectLocation = null;
@@ -99,8 +104,7 @@ public static Result removeFromSourcePath(String sourceFolderUri) {
 		IPath sourceFolderPath = ResourceUtils.filePathFromURI(sourceFolderUri);
 		IProject targetProject = findBelongedProject(sourceFolderPath);
 		if (targetProject != null && !ProjectUtils.isGeneralJavaProject(targetProject)) {
-			String message = ProjectUtils.isGradleProject(targetProject) ? UNSUPPORTED_ON_GRADLE : UNSUPPORTED_ON_MAVEN;
-			return new Result(false, message);
+			return new Result(false, unsupportedOperationMessage(targetProject));
 		}
 
 		IPath projectLocation = null;
@@ -141,52 +145,58 @@ public static Result removeFromSourcePath(String sourceFolderUri) {
 	}
 
 	public static Result listSourcePaths() {
+		try {
+			List<SourcePath> sourcePathList = new ArrayList<>();
+			IProject[] projects = ProjectUtils.getAllProjects();
+			for (IProject project : projects) {
+				if (!ProjectsManager.DEFAULT_PROJECT_NAME.equals(project.getName()) && ProjectUtils.isJavaProject(project)) {
+					sourcePathList.addAll(tryAddProjectToSourcePath(project));
+				}
+			}
+
+			return new ListCommandResult(true, null, sourcePathList.toArray(new SourcePath[0]));
+
+		} catch (JavaModelException e) {
+			JavaLanguageServerPlugin.logException("Failed to resolve the existing source paths in current workspace.", e);
+			return new ListCommandResult(false, e.getMessage());
+		}
+	}
+
+	private static List<SourcePath> tryAddProjectToSourcePath(IProject project) throws JavaModelException {
 		List<SourcePath> sourcePathList = new ArrayList<>();
-		IProject[] projects = ProjectUtils.getAllProjects();
-		for (IProject project : projects) {
-			if (!ProjectsManager.DEFAULT_PROJECT_NAME.equals(project.getName()) && ProjectUtils.isJavaProject(project)) {
-				try {
-					IPath[] paths = ProjectUtils.listSourcePaths(JavaCore.create(project));
-					for (IPath path : paths) {
-						IPath entryPath = path;
-						String projectName = project.getName();
-						String projectType = "General";
-						if (ProjectUtils.isMavenProject(project)) {
-							projectType = "Maven";
-						}
-
-						if (ProjectUtils.isGradleProject(project)) {
-							projectType = "Gradle";
-						}
-
-						IContainer projectRoot = project;
-						if (!ProjectUtils.isVisibleProject(project)) {
-							projectType = "Workspace";
-							IFolder workspaceLinkFolder = project.getFolder(ProjectUtils.WORKSPACE_LINK);
-							if (!workspaceLinkFolder.isLinked()) {
-								continue;
-							}
-
-							projectRoot = workspaceLinkFolder;
-						}
-
-						IPath relativePath = entryPath.makeRelativeTo(projectRoot.getFullPath());
-						IPath location = projectRoot.getRawLocation().append(relativePath);
-						IPath displayPath = getWorkspacePath(location);
-						sourcePathList.add(new SourcePath(location != null ? location.toOSString() : "",
-							displayPath != null ? displayPath.toOSString() : entryPath.toOSString(),
-							entryPath.toOSString(),
-							projectName,
-							projectType));
-					}
-				} catch (JavaModelException e) {
-					JavaLanguageServerPlugin.logException("Failed to resolve the existing source paths in current workspace.", e);
-					return new ListCommandResult(false, e.getMessage());
+		IPath[] paths = ProjectUtils.listSourcePaths(JavaCore.create(project));
+
+		for (IPath path : paths) {
+			IPath entryPath = path;
+			String projectName = project.getName();
+			String projectType = determineProjectType(project);
+
+			IContainer projectRoot = project;
+			if (!ProjectUtils.isVisibleProject(project)) {
+				projectType = "Workspace";
+				IFolder workspaceLinkFolder = project.getFolder(ProjectUtils.WORKSPACE_LINK);
+				if (!workspaceLinkFolder.isLinked()) {
+					continue;
 				}
+
+				projectRoot = workspaceLinkFolder;
 			}
+
+			IPath relativePath = entryPath.makeRelativeTo(projectRoot.getFullPath());
+			IPath location = projectRoot.getRawLocation().append(relativePath);
+			IPath displayPath = getWorkspacePath(location);
+			sourcePathList.add(new SourcePath(location != null ? location.toOSString() : "",
+				displayPath != null ? displayPath.toOSString() : entryPath.toOSString(),
+				entryPath.toOSString(),
+				projectName,
+				projectType));
 		}
 
-		return new ListCommandResult(true, null, sourcePathList.toArray(new SourcePath[0]));
+		return sourcePathList;
+	}
+
+	private static String determineProjectType(IProject project) {
+		return BuildSupportManager.find(project).map(buildSupport -> buildSupport.buildToolName()).orElseGet(() -> "General");
 	}
 
 	private static String[] getInvisibleProjectRelativeSourcePaths(IJavaProject javaProject) throws JavaModelException {
@@ -199,10 +209,9 @@ private static String[] getInvisibleProjectRelativeSourcePaths(IJavaProject java
 		}
 		IPath[] paths = ProjectUtils.listSourcePaths(javaProject);
 		return Arrays.stream(paths)
-				.map(p -> p.makeRelativeTo(workspaceLinkFolder.getFullPath()).toString())
-				.toArray(String[]::new);
+			.map(p -> p.makeRelativeTo(workspaceLinkFolder.getFullPath()).toString())
+			.toArray(String[]::new);
 	}
-
 	private static IProject findBelongedProject(IPath sourceFolder) {
 		List<IProject> projects = Stream.of(ProjectUtils.getAllProjects()).filter(ProjectUtils::isJavaProject).sorted(new Comparator<IProject>() {
 			@Override

org.eclipse.jdt.ls.core/src/org/eclipse/jdt/ls/core/internal/managers/BuildSupportManager.java

@@ -0,0 +1,55 @@
+/*******************************************************************************
+ * Copyright (c) 2021 Red Hat Inc. and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-2.0
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Red Hat Inc. - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.jdt.ls.core.internal.managers;
+
+import java.util.List;
+import java.util.Optional;
+import java.util.function.Predicate;
+
+import org.eclipse.core.resources.IProject;
+import org.eclipse.jdt.ls.core.internal.ExtensionsExtractor;
+import org.eclipse.jdt.ls.core.internal.IConstants;
+
+/**
+ * This is an orchestrator who is responsible for fetching and searching
+ * IBuildSupport objects.
+ *
+ * @author D.Bushenko
+ *
+ */
+public class BuildSupportManager {
+	private static final BuildSupportManager instance = new BuildSupportManager();
+	private List<IBuildSupport> lazyLoadedBuildSupportList;
+
+	private BuildSupportManager() {}
+
+	public static List<IBuildSupport> obtainBuildSupports() {
+		if (instance.lazyLoadedBuildSupportList == null) {
+			instance.lazyLoadedBuildSupportList = ExtensionsExtractor.extractOrderedExtensions(IConstants.PLUGIN_ID, "buildSupport");
+		}
+
+		return instance.lazyLoadedBuildSupportList;
+	}
+
+	public static Optional<IBuildSupport> find(IProject project) {
+		return instance.find(bs -> bs.applies(project));
+	}
+
+	public static Optional<IBuildSupport> find(String buildToolName) {
+		return instance.find(bs -> bs.buildToolName().equalsIgnoreCase(buildToolName));
+	}
+
+	private Optional<IBuildSupport> find(Predicate<? super IBuildSupport> predicate) {
+		return obtainBuildSupports().stream().filter(predicate).findFirst();
+	}
+}

org.eclipse.jdt.ls.core/src/org/eclipse/jdt/ls/core/internal/managers/DefaultProjectBuildSupport.java

@@ -22,4 +22,9 @@ public boolean applies(IProject project) {
 		return JavaLanguageServerPlugin.getProjectsManager().getDefaultProject().equals(project);
 	}
 
+	@Override
+	public String buildToolName() {
+		return InternalBuildSupports.DEFAULT.toString();
+	}
+
 }

org.eclipse.jdt.ls.core/src/org/eclipse/jdt/ls/core/internal/managers/EclipseBuildSupport.java

@@ -103,5 +103,9 @@ public void discoverSource(IClassFile classFile, IProgressMonitor monitor) throw
 		}
 	}
 
+	@Override
+	public String buildToolName() {
+		return InternalBuildSupports.ECLIPSE.toString();
+	}
 
 }