Restore Java 8 compatibility for build tools. (#2300) (#2321)

* Restore Java 8 compatibility for build tools.

Signed-off-by: dblock <dblock@dblock.org>

* Make source code compatible with Java 8.

Signed-off-by: dblock <dblock@dblock.org>

buildSrc/build.gradle

@@ -158,8 +158,8 @@ if (project != rootProject) {
   apply plugin: 'opensearch.publish'
 
   allprojects {
-    targetCompatibility = 11
-    sourceCompatibility = 11
+    targetCompatibility = 8
+    sourceCompatibility = 8
   }
 
   // groovydoc succeeds, but has some weird internal exception...

buildSrc/src/main/groovy/org/opensearch/gradle/ResolveAllDependencies.java

@@ -55,7 +55,7 @@ static boolean canBeResolved(Configuration configuration) {
             return false;
         }
         if (configuration instanceof org.gradle.internal.deprecation.DeprecatableConfiguration) {
-            var deprecatableConfiguration = (DeprecatableConfiguration) configuration;
+            DeprecatableConfiguration deprecatableConfiguration = (DeprecatableConfiguration) configuration;
             if (deprecatableConfiguration.canSafelyBeResolved() == false) {
                 return false;
             }

buildSrc/src/main/java/org/opensearch/gradle/LoggedExec.java

@@ -64,7 +64,6 @@
 /**
  * A wrapper around gradle's Exec task to capture output and log on error.
  */
-@SuppressWarnings("unchecked")
 public class LoggedExec extends Exec implements FileSystemOperationsAware {
 
     private static final Logger LOGGER = Logging.getLogger(LoggedExec.class);

buildSrc/src/main/java/org/opensearch/gradle/OpenSearchJavaPlugin.java

@@ -63,8 +63,8 @@
 import org.gradle.language.base.plugins.LifecycleBasePlugin;
 
 import java.io.File;
+import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
 import java.util.function.Consumer;
 
 import static org.opensearch.gradle.util.Util.toStringable;
@@ -212,10 +212,12 @@ static void configureJars(Project project) {
                 public void execute(Task task) {
                     // this doFirst is added before the info plugin, therefore it will run
                     // after the doFirst added by the info plugin, and we can override attributes
-                    jarTask.getManifest()
-                        .attributes(
-                            Map.of("Build-Date", BuildParams.getBuildDate(), "Build-Java-Version", BuildParams.getGradleJavaVersion())
-                        );
+                    jarTask.getManifest().attributes(new HashMap<String, Object>() {
+                        {
+                            put("Build-Date", BuildParams.getBuildDate());
+                            put("Build-Java-Version", BuildParams.getGradleJavaVersion());
+                        }
+                    });
                 }
             });
         });

buildSrc/src/main/java/org/opensearch/gradle/OpenSearchTestBasePlugin.java

@@ -49,6 +49,7 @@
 import org.gradle.api.tasks.testing.Test;
 
 import java.io.File;
+import java.util.HashMap;
 import java.util.Map;
 
 import static org.opensearch.gradle.util.FileUtils.mkdirs;
@@ -95,7 +96,7 @@ public void apply(Project project) {
 
             // We specifically use an anonymous inner class here because lambda task actions break Gradle cacheability
             // See: https://docs.gradle.org/current/userguide/more_about_tasks.html#sec:how_does_it_work
-            test.doFirst(new Action<>() {
+            test.doFirst(new Action<Task>() {
                 @Override
                 public void execute(Task t) {
                     mkdirs(testOutputDir);
@@ -137,20 +138,16 @@ public void execute(Task t) {
                 test.jvmArgs("-ea", "-esa");
             }
 
-            Map<String, String> sysprops = Map.of(
-                "java.awt.headless",
-                "true",
-                "tests.gradle",
-                "true",
-                "tests.artifact",
-                project.getName(),
-                "tests.task",
-                test.getPath(),
-                "tests.security.manager",
-                "true",
-                "jna.nosys",
-                "true"
-            );
+            Map<String, String> sysprops = new HashMap<String, String>() {
+                {
+                    put("java.awt.headless", "true");
+                    put("tests.gradle", "true");
+                    put("tests.artifact", project.getName());
+                    put("tests.task", test.getPath());
+                    put("tests.security.manager", "true");
+                    put("jna.nosys", "true");
+                }
+            };
             test.systemProperties(sysprops);
 
             // ignore changing test seed when build is passed -Dignore.tests.seed for cacheability experimentation

buildSrc/src/main/java/org/opensearch/gradle/ReaperPlugin.java

@@ -36,6 +36,7 @@
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
 
+import java.lang.management.ManagementFactory;
 import java.nio.file.Path;
 
 /**
@@ -51,14 +52,31 @@ public void apply(Project project) {
 
         project.getPlugins().apply(GlobalBuildInfoPlugin.class);
 
-        Path inputDir = project.getRootDir()
-            .toPath()
-            .resolve(".gradle")
-            .resolve("reaper")
-            .resolve("build-" + ProcessHandle.current().pid());
+        Path inputDir = project.getRootDir().toPath().resolve(".gradle").resolve("reaper").resolve("build-" + getProcessId("xx"));
         ReaperService service = project.getExtensions()
             .create("reaper", ReaperService.class, project, project.getBuildDir().toPath(), inputDir);
 
         project.getGradle().buildFinished(result -> service.shutdown());
     }
+
+    private static String getProcessId(final String fallback) {
+        // Note: may fail in some JVM implementations
+        // therefore fallback has to be provided
+
+        // something like '<pid>@<hostname>', at least in SUN / Oracle JVMs
+        final String jvmName = ManagementFactory.getRuntimeMXBean().getName();
+        final int index = jvmName.indexOf('@');
+
+        if (index < 1) {
+            // part before '@' empty (index = 0) / '@' not found (index = -1)
+            return fallback;
+        }
+
+        try {
+            return Long.toString(Long.parseLong(jvmName.substring(0, index)));
+        } catch (NumberFormatException e) {
+            // ignore
+        }
+        return fallback;
+    }
 }

buildSrc/src/main/java/org/opensearch/gradle/ReaperService.java

@@ -179,7 +179,11 @@ private Path locateReaperJar() {
                 InputStream jarInput = this.getClass().getResourceAsStream("/META-INF/reaper.jar");
             ) {
                 logger.info("Copying reaper.jar...");
-                jarInput.transferTo(out);
+                byte[] buffer = new byte[4096];
+                int len;
+                while ((len = jarInput.read(buffer)) > 0) {
+                    out.write(buffer, 0, len);
+                }
             } catch (IOException e) {
                 throw new UncheckedIOException(e);
             }

buildSrc/src/main/java/org/opensearch/gradle/docker/DockerSupportService.java

@@ -49,6 +49,7 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
@@ -280,7 +281,7 @@ static Map<String, String> parseOsRelease(final List<String> osReleaseLines) {
      */
     private Optional<String> getDockerPath() {
         // Check if the Docker binary exists
-        return List.of(DOCKER_BINARIES).stream().filter(path -> new File(path).exists()).findFirst();
+        return Arrays.asList(DOCKER_BINARIES).stream().filter(path -> new File(path).exists()).findFirst();
     }
 
     /**
@@ -291,7 +292,7 @@ private Optional<String> getDockerPath() {
      */
     private Optional<String> getDockerComposePath() {
         // Check if the Docker binary exists
-        return List.of(DOCKER_COMPOSE_BINARIES).stream().filter(path -> new File(path).exists()).findFirst();
+        return Arrays.asList(DOCKER_COMPOSE_BINARIES).stream().filter(path -> new File(path).exists()).findFirst();
     }
 
     private void throwDockerRequiredException(final String message) {

buildSrc/src/main/java/org/opensearch/gradle/internal/InternalBwcGitPlugin.java

@@ -109,7 +109,7 @@ public void apply(Project project) {
         });
 
         TaskProvider<LoggedExec> fetchLatestTaskProvider = tasks.register("fetchLatest", LoggedExec.class, fetchLatest -> {
-            var gitFetchLatest = project.getProviders()
+            Provider<Object> gitFetchLatest = project.getProviders()
                 .systemProperty("tests.bwc.git_fetch_latest")
                 .forUseAtConfigurationTime()
                 .orElse("true")
@@ -122,7 +122,7 @@ public void apply(Project project) {
                     }
                     throw new GradleException("tests.bwc.git_fetch_latest must be [true] or [false] but was [" + fetchProp + "]");
                 });
-            fetchLatest.onlyIf(t -> project.getGradle().getStartParameter().isOffline() == false && gitFetchLatest.get());
+            fetchLatest.onlyIf(t -> project.getGradle().getStartParameter().isOffline() == false && gitFetchLatest.get() != null);
             fetchLatest.dependsOn(addRemoteTaskProvider);
             fetchLatest.setWorkingDir(gitExtension.getCheckoutDir().get());
             fetchLatest.setCommandLine(asList("git", "fetch", "--all"));

buildSrc/src/main/java/org/opensearch/gradle/internal/InternalDistributionArchiveSetupPlugin.java

@@ -39,13 +39,15 @@
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
 import org.gradle.api.Task;
+import org.gradle.api.artifacts.Configuration;
 import org.gradle.api.artifacts.type.ArtifactTypeDefinition;
 import org.gradle.api.plugins.BasePlugin;
 import org.gradle.api.logging.Logger;
 import org.gradle.api.logging.Logging;
 import org.gradle.api.tasks.AbstractCopyTask;
 import org.gradle.api.tasks.Sync;
 import org.gradle.api.tasks.TaskContainer;
+import org.gradle.api.tasks.TaskProvider;
 import org.gradle.api.tasks.bundling.AbstractArchiveTask;
 import org.gradle.api.tasks.bundling.Compression;
 import org.gradle.api.tasks.bundling.Zip;
@@ -105,14 +107,18 @@ private Action<Task> configure(String name) {
 
     private void registerAndConfigureDistributionArchivesExtension(Project project) {
         container = project.container(DistributionArchive.class, name -> {
-            var subProjectDir = archiveToSubprojectName(name);
-            var copyDistributionTaskName = "build" + capitalize(name.substring(0, name.length() - 3));
+            String subProjectDir = archiveToSubprojectName(name);
+            String copyDistributionTaskName = "build" + capitalize(name.substring(0, name.length() - 3));
             TaskContainer tasks = project.getTasks();
-            var explodedDist = tasks.register(copyDistributionTaskName, Sync.class, sync -> sync.into(subProjectDir + "/build/install/"));
+            TaskProvider<Sync> explodedDist = tasks.register(
+                copyDistributionTaskName,
+                Sync.class,
+                sync -> sync.into(subProjectDir + "/build/install/")
+            );
             explodedDist.configure(configure(name));
-            var archiveTaskName = "build" + capitalize(name);
+            String archiveTaskName = "build" + capitalize(name);
 
-            var archiveTask = name.endsWith("Tar")
+            TaskProvider<? extends AbstractArchiveTask> archiveTask = name.endsWith("Tar")
                 ? tasks.register(archiveTaskName, SymbolicLinkPreservingTar.class)
                 : tasks.register(archiveTaskName, Zip.class);
             archiveTask.configure(configure(name));
@@ -122,11 +128,11 @@ private void registerAndConfigureDistributionArchivesExtension(Project project)
         // Each defined distribution archive is linked to a subproject.
         // A distribution archive definition not matching a sub project will result in build failure.
         container.whenObjectAdded(distributionArchive -> {
-            var subProjectName = archiveToSubprojectName(distributionArchive.getName());
+            String subProjectName = archiveToSubprojectName(distributionArchive.getName());
             project.project(subProjectName, sub -> {
                 sub.getPlugins().apply(BasePlugin.class);
                 sub.getArtifacts().add(DEFAULT_CONFIGURATION_NAME, distributionArchive.getArchiveTask());
-                var extractedConfiguration = sub.getConfigurations().create("extracted");
+                Configuration extractedConfiguration = sub.getConfigurations().create("extracted");
                 extractedConfiguration.setCanBeResolved(false);
                 extractedConfiguration.getAttributes().attribute(ARTIFACT_FORMAT, ArtifactTypeDefinition.DIRECTORY_TYPE);
                 sub.getArtifacts().add(EXTRACTED_CONFIGURATION_NAME, distributionArchive.getExpandedDistTask());

buildSrc/src/main/java/org/opensearch/gradle/precommit/ForbiddenApisPrecommitPlugin.java

@@ -48,8 +48,9 @@
 
 import java.nio.file.Path;
 import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
 import java.util.List;
-import java.util.Set;
 
 public class ForbiddenApisPrecommitPlugin extends PrecommitPlugin {
     @Override
@@ -90,14 +91,14 @@ public TaskProvider<? extends Task> createTask(Project project) {
                 // TODO: forbidden apis does not yet support java 15, rethink using runtime version
                 t.setTargetCompatibility(JavaVersion.VERSION_14.getMajorVersion());
             }
-            t.setBundledSignatures(Set.of("jdk-unsafe", "jdk-deprecated", "jdk-non-portable", "jdk-system-out"));
+            t.setBundledSignatures(new HashSet<>(Arrays.asList("jdk-unsafe", "jdk-deprecated", "jdk-non-portable", "jdk-system-out")));
             t.setSignaturesFiles(
                 project.files(
                     resourcesDir.resolve("forbidden/jdk-signatures.txt"),
                     resourcesDir.resolve("forbidden/opensearch-all-signatures.txt")
                 )
             );
-            t.setSuppressAnnotations(Set.of("**.SuppressForbidden"));
+            t.setSuppressAnnotations(new HashSet<>(Arrays.asList("**.SuppressForbidden")));
             if (t.getName().endsWith("Test")) {
                 t.setSignaturesFiles(
                     t.getSignaturesFiles()

buildSrc/src/main/java/org/opensearch/gradle/precommit/ValidateJsonNoKeywordsTask.java

@@ -51,6 +51,7 @@
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.PrintWriter;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
@@ -126,14 +127,17 @@ public void validate(InputChanges inputChanges) {
                     final JsonNode jsonNode = mapper.readTree(file);
 
                     if (jsonNode.isObject() == false) {
-                        errors.put(file, Set.of("Expected an object, but found: " + jsonNode.getNodeType()));
+                        errors.put(file, new HashSet<>(Arrays.asList("Expected an object, but found: " + jsonNode.getNodeType())));
                         return;
                     }
 
                     final ObjectNode rootNode = (ObjectNode) jsonNode;
 
                     if (rootNode.size() != 1) {
-                        errors.put(file, Set.of("Expected an object with exactly 1 key, but found " + rootNode.size() + " keys"));
+                        errors.put(
+                            file,
+                            new HashSet<>(Arrays.asList("Expected an object with exactly 1 key, but found " + rootNode.size() + " keys"))
+                        );
                         return;
                     }
 
@@ -148,7 +152,7 @@ public void validate(InputChanges inputChanges) {
                         }
                     }
                 } catch (IOException e) {
-                    errors.put(file, Set.of("Failed to load file: " + e.getMessage()));
+                    errors.put(file, new HashSet<>(Arrays.asList("Failed to load file: " + e.getMessage())));
                 }
             });
 

buildSrc/src/main/java/org/opensearch/gradle/test/DistroTestPlugin.java

@@ -70,6 +70,7 @@
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Map.Entry;
 import java.util.function.Supplier;
 import java.util.stream.Stream;
 
@@ -204,7 +205,7 @@ public void apply(Project project) {
                     vmDependencies
                 );
             } else {
-                for (var entry : linuxTestTasks.entrySet()) {
+                for (Entry<OpenSearchDistribution.Type, List<TaskProvider<Test>>> entry : linuxTestTasks.entrySet()) {
                     OpenSearchDistribution.Type type = entry.getKey();
                     TaskProvider<?> vmLifecycleTask = vmLifecyleTasks.get(type);
                     configureVMWrapperTasks(vmProject, entry.getValue(), depsTasks, wrapperTask -> {
@@ -227,7 +228,7 @@ public void apply(Project project) {
                     }, vmDependencies);
                 }
 
-                for (var entry : upgradeTestTasks.entrySet()) {
+                for (Entry<String, List<TaskProvider<Test>>> entry : upgradeTestTasks.entrySet()) {
                     String version = entry.getKey();
                     TaskProvider<?> vmVersionTask = vmVersionTasks.get(version);
                     configureVMWrapperTasks(
@@ -321,7 +322,12 @@ private static Object convertPath(
     private static Configuration configureExamplePlugin(Project project) {
         Configuration examplePlugin = project.getConfigurations().create(EXAMPLE_PLUGIN_CONFIGURATION);
         DependencyHandler deps = project.getDependencies();
-        Map<String, String> examplePluginProject = Map.of("path", ":example-plugins:custom-settings", "configuration", "zip");
+        Map<String, String> examplePluginProject = new HashMap<String, String>() {
+            {
+                put("path", ":example-plugins:custom-settings");
+                put("configuration", "zip");
+            }
+        };
         deps.add(EXAMPLE_PLUGIN_CONFIGURATION, deps.project(examplePluginProject));
         return examplePlugin;
     }

buildSrc/src/main/java/org/opensearch/gradle/test/rest/CopyRestApiTask.java

@@ -164,7 +164,7 @@ void copy() {
             getFileSystemOperations().copy(c -> {
                 c.from(getArchiveOperations().zipTree(coreConfig.getSingleFile()));
                 // this ends up as the same dir as outputDir
-                c.into(Objects.requireNonNull(getSourceSet().orElseThrow().getOutput().getResourcesDir()));
+                c.into(Objects.requireNonNull(getSourceSet().get().getOutput().getResourcesDir()));
                 if (includeCore.get().isEmpty()) {
                     c.include(REST_API_PREFIX + "/**");
                 } else {

buildSrc/src/main/java/org/opensearch/gradle/test/rest/CopyRestTestsTask.java

@@ -155,7 +155,7 @@ void copy() {
                 getFileSystemOperations().copy(c -> {
                     c.from(getArchiveOperations().zipTree(coreConfig.getSingleFile()));
                     // this ends up as the same dir as outputDir
-                    c.into(Objects.requireNonNull(getSourceSet().orElseThrow().getOutput().getResourcesDir()));
+                    c.into(Objects.requireNonNull(getSourceSet().get().getOutput().getResourcesDir()));
                     c.include(
                         includeCore.get().stream().map(prefix -> REST_TEST_PREFIX + "/" + prefix + "*/**").collect(Collectors.toList())
                     );