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mtoffl01datadog-datadog-prod-us1[bot]mcculls
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Provide access to VM arguments via shared CLIHelper (#8538)
* Abstract away getVMArgumentsThroughReflection into a VMArgsCache class * Change underlying data structure of VMArgsCache to HashSet * Update internal-api/src/main/java/datadog/trace/bootstrap/config/provider/VMArgsCache.java Co-authored-by: datadog-datadog-prod-us1[bot] <88084959+datadog-datadog-prod-us1[bot]@users.noreply.github.com> * Update internal-api/src/main/java/datadog/trace/bootstrap/config/provider/VMArgsCache.java Co-authored-by: datadog-datadog-prod-us1[bot] <88084959+datadog-datadog-prod-us1[bot]@users.noreply.github.com> * Update internal-api/src/main/java/datadog/trace/bootstrap/config/provider/VMArgsCache.java Co-authored-by: datadog-datadog-prod-us1[bot] <88084959+datadog-datadog-prod-us1[bot]@users.noreply.github.com> * Clean up for initial review * move VMArgsCache to components/cli * fix datadog.cli import * nits: remove outdated comments * annotate initJvmArgs with @SuppressForbidden to allow Class.forName() usage * Fix package directory * Cleanup code: * store args in static field, make available via static getter * use list of strings as storage type to begin with * prefer NIO methods to read content (defaults to UTF8) * use try-with-resources to ensure reader is closed * check file exists as a quick short-circuit * Remove warning when reflection fails * Expose components:cli from internal-api --------- Co-authored-by: datadog-datadog-prod-us1[bot] <88084959+datadog-datadog-prod-us1[bot]@users.noreply.github.com> Co-authored-by: Stuart McCulloch <[email protected]>
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9 files changed

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‎components/cli/build.gradle.kts‎

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plugins {
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id("me.champeau.jmh")
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}
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apply(from = "$rootDir/gradle/java.gradle")
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jmh {
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version = "1.28"
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}

‎components/cli/src/main/java/datadog/cli/CLIHelper.java‎

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package datadog.cli;
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import de.thetaphi.forbiddenapis.SuppressForbidden;
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import java.io.BufferedReader;
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import java.lang.management.ManagementFactory;
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import java.lang.reflect.Field;
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import java.nio.file.Files;
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import java.nio.file.Path;
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import java.nio.file.Paths;
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import java.util.Arrays;
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import java.util.Collections;
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import java.util.List;
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import java.util.Locale;
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public final class CLIHelper {
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private static final List<String> VM_ARGS = findVmArgs();
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public static List<String> getVmArgs() {
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return VM_ARGS;
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}
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@SuppressForbidden
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private static List<String> findVmArgs() {
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// Try ProcFS on Linux
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try {
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if (isLinux()) {
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Path cmdlinePath = Paths.get("/proc/self/cmdline");
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if (Files.exists(cmdlinePath)) {
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try (BufferedReader in = Files.newBufferedReader(cmdlinePath)) {
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return Arrays.asList(in.readLine().split("\0"));
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}
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}
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}
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} catch (Throwable ignored) {
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// Ignored exception
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}
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// Try Oracle-based
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// IBM Semeru Runtime 1.8.0_345-b01 will throw UnsatisfiedLinkError here.
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try {
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final Class<?> managementFactoryHelperClass =
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Class.forName("sun.management.ManagementFactoryHelper");
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final Class<?> vmManagementClass = Class.forName("sun.management.VMManagement");
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Object vmManagement;
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try {
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vmManagement =
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managementFactoryHelperClass.getDeclaredMethod("getVMManagement").invoke(null);
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} catch (final NoSuchMethodException e) {
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// Older vm before getVMManagement() existed
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final Field field = managementFactoryHelperClass.getDeclaredField("jvm");
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field.setAccessible(true);
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vmManagement = field.get(null);
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field.setAccessible(false);
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}
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//noinspection unchecked
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return (List<String>) vmManagementClass.getMethod("getVmArguments").invoke(vmManagement);
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} catch (final ReflectiveOperationException | UnsatisfiedLinkError ignored) {
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// Ignored exception
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}
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// Try IBM-based.
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try {
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final Class<?> VMClass = Class.forName("com.ibm.oti.vm.VM");
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final String[] argArray = (String[]) VMClass.getMethod("getVMArgs").invoke(null);
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return Arrays.asList(argArray);
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} catch (final ReflectiveOperationException ignored) {
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// Ignored exception
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}
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// Fallback to default
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try {
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return ManagementFactory.getRuntimeMXBean().getInputArguments();
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} catch (final Throwable t) {
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// Throws InvocationTargetException on modularized applications
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// with non-opened java.management module
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System.err.println("WARNING: Unable to get VM args using managed beans");
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}
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return Collections.emptyList();
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}
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private static boolean isLinux() {
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return System.getProperty("os.name").toLowerCase(Locale.ROOT).contains("linux");
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}
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}

‎dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/Constants.java‎

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@@ -17,6 +17,7 @@ public final class Constants {
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"datadog.slf4j",
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"datadog.json",
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"datadog.context",
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"datadog.cli",
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"datadog.appsec.api",
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"datadog.trace.api",
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"datadog.trace.bootstrap",

‎dd-java-agent/build.gradle‎

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@@ -203,6 +203,7 @@ tasks.withType(GenerateMavenPom).configureEach { task ->
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dependencies {
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implementation project(path: ':components:json')
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implementation project(path: ':components:cli')
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modules {
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module("com.squareup.okio:okio") {
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replacedBy("com.datadoghq.okio:okio") // embed our patched fork

‎dd-java-agent/src/main/java/datadog/trace/bootstrap/AgentBootstrap.java‎

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import static java.nio.charset.StandardCharsets.UTF_8;
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import datadog.cli.CLIHelper;
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import de.thetaphi.forbiddenapis.SuppressForbidden;
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import java.io.BufferedReader;
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import java.io.File;
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import java.io.IOException;
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import java.io.InputStreamReader;
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import java.io.PrintStream;
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import java.lang.instrument.Instrumentation;
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import java.lang.management.ManagementFactory;
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import java.lang.reflect.Field;
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import java.lang.reflect.Method;
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import java.net.URI;
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import java.net.URISyntaxException;
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import java.net.URL;
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import java.security.CodeSource;
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import java.util.ArrayList;
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import java.util.Arrays;
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import java.util.Collections;
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import java.util.IdentityHashMap;
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import java.util.List;
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// - On IBM-based JDKs since at least 1.7
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// This prevents custom log managers from working correctly
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// Use reflection to bypass the loading of the class~
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for (final String argument : getVMArgumentsThroughReflection()) {
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for (final String argument : CLIHelper.getVmArgs()) {
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if (argument.startsWith(JAVA_AGENT_ARGUMENT)) {
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int index = argument.indexOf('=', JAVA_AGENT_ARGUMENT.length());
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String agentPathname =
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return javaagentFile;
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}
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@SuppressForbidden
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private static List<String> getVMArgumentsThroughReflection() {
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// Try Oracle-based
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// IBM Semeru Runtime 1.8.0_345-b01 will throw UnsatisfiedLinkError here.
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try {
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final Class<?> managementFactoryHelperClass =
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Class.forName("sun.management.ManagementFactoryHelper");
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final Class<?> vmManagementClass = Class.forName("sun.management.VMManagement");
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Object vmManagement;
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try {
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vmManagement =
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managementFactoryHelperClass.getDeclaredMethod("getVMManagement").invoke(null);
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} catch (final NoSuchMethodException e) {
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// Older vm before getVMManagement() existed
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final Field field = managementFactoryHelperClass.getDeclaredField("jvm");
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field.setAccessible(true);
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vmManagement = field.get(null);
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field.setAccessible(false);
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}
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//noinspection unchecked
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return (List<String>) vmManagementClass.getMethod("getVmArguments").invoke(vmManagement);
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} catch (final ReflectiveOperationException | UnsatisfiedLinkError ignored) {
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// Ignored exception
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}
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// Try IBM-based.
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try {
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final Class<?> VMClass = Class.forName("com.ibm.oti.vm.VM");
459-
final String[] argArray = (String[]) VMClass.getMethod("getVMArgs").invoke(null);
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return Arrays.asList(argArray);
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} catch (final ReflectiveOperationException ignored) {
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// Ignored exception
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}
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// Fallback to default
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try {
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System.err.println(
468-
"WARNING: Unable to get VM args through reflection. A custom java.util.logging.LogManager may not work correctly");
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return ManagementFactory.getRuntimeMXBean().getInputArguments();
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} catch (final Throwable t) {
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// Throws InvocationTargetException on modularized applications
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// with non-opened java.management module
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System.err.println("WARNING: Unable to get VM args using managed beans");
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}
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return Collections.emptyList();
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}
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private static void checkJarManifestMainClassIsThis(final URL jarUrl) throws IOException {
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final URL manifestUrl = new URL("jar:" + jarUrl + "!/META-INF/MANIFEST.MF");
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final String mainClassLine = "Main-Class: " + thisClass.getCanonicalName();

‎dd-java-agent/testing/src/main/groovy/datadog/trace/agent/test/SpockRunner.java‎

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"datadog.slf4j",
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"datadog.json",
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"datadog.context",
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"datadog.cli",
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"datadog.appsec.api",
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"datadog.trace.api",
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"datadog.trace.bootstrap",

‎gradle/dependencies.gradle‎

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exclude(project(':communication'))
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exclude(project(':components:context'))
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exclude(project(':components:json'))
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exclude(project(':components:cli'))
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exclude(project(':remote-config:remote-config-api'))
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exclude(project(':remote-config:remote-config-core'))
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exclude(project(':telemetry'))

‎internal-api/build.gradle‎

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api project(':dd-trace-api')
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api libs.slf4j
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api project(':components:context')
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api project(':components:cli')
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api project(":utils:time-utils")
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// has to be loaded by system classloader:

‎settings.gradle‎

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include ':dd-java-agent:agent-otel:otel-tooling'
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include ':communication'
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include ':components:cli'
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include ':components:context'
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include ':components:json'
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include ':telemetry'

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