Import Gradle project via Buildship if Gradle Build Server is not available

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

@@ -114,6 +114,19 @@ public class GradleProjectImporter extends AbstractProjectImporter {
 	public static final String GRADLE_MARKER_COLUMN_START = "gradleColumnStart";
 	public static final String GRADLE_MARKER_COLUMN_END = "gradleColumnEnd";
 
+	/**
+	 * Nature id of the gradle build server project.
+	 */
+	public static final String GRADLE_BUILD_SERVER_NATURE = "com.microsoft.gradle.bs.importer.GradleBuildServerProjectNature";
+	/**
+	 * Builder id of the gradle build server.
+	 */
+	public static final String GRADLE_BUILD_SERVER_BUILDER_ID = "com.microsoft.gradle.bs.importer.builder.BuildServerBuilder";
+	/**
+	 * Builder id of the java problem checker, it's used to provide diagnostics during auto build for gradle build server projects.
+	 */
+	public static final String JAVA_PROBLEM_CHECKER_ID = "java.bs.JavaProblemChecker";
+
 	private static final int GRADLE_RELATED = 0x00080000;
 	private static final int INVALID_TYPE_CODE_ID = GRADLE_RELATED + 1;
 
@@ -152,7 +165,11 @@ public boolean applies(IProgressMonitor monitor) throws CoreException {
 					.addExclusions("**/build")//default gradle build dir
 					.addExclusions("**/bin");
 			for (IProject project : ProjectUtils.getAllProjects()) {
-				if (!ProjectUtils.isGradleProject(project)) {
+				// The gradle build server has higher priority than buildship when importing gradle projects.
+				// If code goes here, it means that the project cannot be imported by gradle build server.
+				// The buildship should try to import it if it can. And the buildship importer should clean
+				// up the configurations of the gradle build server in the project description if it has.
+				if (!ProjectUtils.isGradleProject(project) && !ProjectUtils.hasNature(project, GRADLE_BUILD_SERVER_NATURE)) {
 					String path = project.getLocation().toOSString();
 					gradleDetector.addExclusions(path.replace("\\", "\\\\"));
 				}
@@ -301,7 +318,7 @@ public void importToWorkspace(IProgressMonitor monitor) throws CoreException {
 		}
 
 		GradleUtils.synchronizeAnnotationProcessingConfiguration(subMonitor);
-
+		eliminateBuildServerFootprint(monitor);
 		subMonitor.done();
 	}
 
@@ -707,6 +724,27 @@ public static boolean isFailedStatus(IStatus status) {
 		return status != null && !status.isOK() && status.getException() != null;
 	}
 
+	/**
+	 * Eliminate the footprint of the Gradle build server projects. This is necessary
+	 * cleanup in case that user uninstalls/disables the gradle extension.
+	 */
+	private static void eliminateBuildServerFootprint(IProgressMonitor monitor) {
+		for (IProject project : ProjectUtils.getAllProjects()) {
+			try {
+				if (ProjectUtils.hasNature(project, GRADLE_BUILD_SERVER_NATURE)) {
+					GradleUtils.removeConfigurationFromProjectDescription(
+						project,
+						new HashSet<>(Arrays.asList(GRADLE_BUILD_SERVER_NATURE)),
+						new HashSet<>(Arrays.asList(GRADLE_BUILD_SERVER_BUILDER_ID, JAVA_PROBLEM_CHECKER_ID)),
+						monitor
+					);
+				}
+			} catch (CoreException e) {
+				JavaLanguageServerPlugin.logException("Failed to remove Gradle build server configuration from project description", e);
+			}
+		}
+	}
+
 	public class GradleCompatibilityStatus extends Status {
 
 		private String projectUri;

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

@@ -24,8 +24,10 @@
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -38,7 +40,11 @@
 import org.eclipse.buildship.core.GradleBuild;
 import org.eclipse.buildship.core.GradleCore;
 import org.eclipse.buildship.core.internal.util.gradle.GradleVersion;
+import org.eclipse.core.resources.ICommand;
 import org.eclipse.core.resources.IProject;
+import org.eclipse.core.resources.IProjectDescription;
+import org.eclipse.core.resources.IResource;
+import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.FileLocator;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.IStatus;
@@ -381,4 +387,33 @@ public static Map<String, File> getAllVmInstalls() {
 	public static String getMajorJavaVersion(String version) {
 		return CompilerOptions.versionFromJdkLevel(CompilerOptions.versionToJdkLevel(version));
 	}
+
+	/**
+	 * Remove the given nature id and builder name from the project description.
+	 * @param project the project.
+	 * @param natureIdsToRemove the nature ids to remove.
+	 * @param builderNameToRemove the builder names to remove.
+	 */
+	public static void removeConfigurationFromProjectDescription(IProject project, Collection<String> natureIdsToRemove,
+			Collection<String> builderNameToRemove, IProgressMonitor monitor) throws CoreException {
+		IProjectDescription description = project.getDescription();
+		ICommand[] commands = description.getBuildSpec();
+		List<ICommand> newSpecs = new LinkedList<>();
+		for (ICommand command : commands) {
+			if (!builderNameToRemove.contains(command.getBuilderName())) {
+				newSpecs.add(command);
+			}
+		}
+		description.setBuildSpec(newSpecs.toArray(new ICommand[newSpecs.size()]));
+
+		String[] natureIds = description.getNatureIds();
+		List<String> newNatureIds = new LinkedList<>();
+		for (String natureId : natureIds) {
+			if (!natureIdsToRemove.contains(natureId)) {
+				newNatureIds.add(natureId);
+			}
+		}
+		description.setNatureIds(newNatureIds.toArray(new String[newNatureIds.size()]));
+		project.setDescription(description, IResource.AVOID_NATURE_CONFIG ,monitor);
+	}
 }

org.eclipse.jdt.ls.tests/projects/gradle/gradle-build-server/.project

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>gradle-build-server</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>java.bs.JavaProblemChecker</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>com.microsoft.gradle.bs.importer.builder.BuildServerBuilder</name>
+			<triggers>full,incremental,</triggers>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+		<nature>com.microsoft.gradle.bs.importer.GradleBuildServerProjectNature</nature>
+	</natures>
+</projectDescription>

org.eclipse.jdt.ls.tests/projects/gradle/gradle-build-server/build.gradle

@@ -0,0 +1 @@
+apply plugin: 'java'

org.eclipse.jdt.ls.tests/projects/gradle/gradle-build-server/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+#Wed Aug 10 11:28:36 CST 2022
+distributionBase=GRADLE_USER_HOME
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.3.3-bin.zip
+distributionPath=wrapper/dists
+zipStorePath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME

org.eclipse.jdt.ls.tests/projects/gradle/gradle-build-server/gradlew

@@ -0,0 +1,183 @@
+#!/usr/bin/env sh
+
+#
+# Copyright 2015 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.
+#
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=`expr $i + 1`
+    done
+    case $i in
+        0) set -- ;;
+        1) set -- "$args0" ;;
+        2) set -- "$args0" "$args1" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=`save "$@"`
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+exec "$JAVACMD" "$@"