Improve instrumented test agent creation (#9519)

Author: PerfectSlayer

dd-java-agent/instrumentation-testing/src/main/java/datadog/trace/agent/test/BootstrapClasspathSetupListener.java

@@ -1,10 +1,7 @@
 package datadog.trace.agent.test;
 
-import static com.google.common.base.StandardSystemProperty.JAVA_CLASS_PATH;
-import static com.google.common.base.StandardSystemProperty.PATH_SEPARATOR;
+import static java.io.File.pathSeparator;
 
-import com.google.common.base.Splitter;
-import com.google.common.collect.ImmutableList;
 import com.google.common.reflect.ClassPath;
 import datadog.trace.agent.test.utils.ClasspathUtils;
 import datadog.trace.bootstrap.BootstrapProxy;
@@ -14,9 +11,11 @@
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.net.URLClassLoader;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.TreeSet;
@@ -111,26 +110,28 @@ private static ClassPath computeTestClasspath() {
    */
   @SuppressForbidden
   private static ClassLoader buildJavaClassPathClassLoader() {
-    final ImmutableList.Builder<URL> urls = ImmutableList.builder();
-    for (final String entry : Splitter.on(PATH_SEPARATOR.value()).split(JAVA_CLASS_PATH.value())) {
+    List<URL> urls = new ArrayList<>();
+    String classPath = System.getProperty("java.class.path", "");
+    for (String entry : classPath.split(pathSeparator)) {
       try {
+        File pathEntry = new File(entry);
         try {
-          urls.add(new File(entry).toURI().toURL());
-        } catch (final SecurityException e) { // File.toURI checks to see if the file is a directory
-          urls.add(new URL("file", null, new File(entry).getAbsolutePath()));
+          urls.add(pathEntry.toURI().toURL());
+        } catch (final SecurityException e) {
+          urls.add(new URL("file", null, pathEntry.getAbsolutePath()));
         }
       } catch (final MalformedURLException e) {
         System.err.printf(
             "Error injecting bootstrap jar: Malformed classpath entry: %s. %s%n", entry, e);
       }
     }
-    return new URLClassLoader(urls.build().toArray(new URL[0]), null);
+    return new URLClassLoader(urls.toArray(new URL[0]), null);
   }
 
   private static void setupBootstrapClasspath() {
     // Ensure there weren't any bootstrap classes loaded prematurely.
     Set<String> prematureBootstrapClasses = new TreeSet<>();
-    for (Class clazz : ByteBuddyAgent.getInstrumentation().getAllLoadedClasses()) {
+    for (Class<?> clazz : ByteBuddyAgent.getInstrumentation().getAllLoadedClasses()) {
       if (isBootstrapClass(clazz)
           && clazz.getClassLoader() != null
           && !clazz.getName().equals("datadog.trace.api.DisableTestTrace")

dd-java-agent/instrumentation/play-ws-1/src/test/groovy/PlayWSClientTest.groovy

@@ -54,7 +54,7 @@ class PlayJavaStreamedWSClientTest extends PlayWSClientTestBase {
         runInAdHocThread(callback)
       }).toCompletableFuture().get(5, TimeUnit.SECONDS)
 
-    // The status can be ready before the body so explicity call wait for body to be ready
+    // The status can be ready before the body so explicitly call wait for body to be ready
     wsResponse.getBodyAsSource().runFold("", { acc, out -> "" }, materializer)
     .toCompletableFuture().get(5, TimeUnit.SECONDS)
     return wsResponse.getStatus()
@@ -119,7 +119,7 @@ class PlayScalaStreamedWSClientTest extends PlayWSClientTestBase {
 
     play.api.libs.ws.StandaloneWSResponse wsResponse = Await.result(futureResponse, Duration.apply(5, TimeUnit.SECONDS))
 
-    // The status can be ready before the body so explicity call wait for body to be ready
+    // The status can be ready before the body so explicitly call wait for body to be ready
     Await.result(
       wsResponse.bodyAsSource().runFold("", { acc, out -> "" }, materializer),
       Duration.apply(5, TimeUnit.SECONDS))

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

@@ -47,27 +47,24 @@ public static byte[] convertToByteArray(final Class<?> clazz) throws IOException
    * @param loader classloader used to load bytes
    * @param resourceNames names of resources to copy into the new jar
    * @return the location of the newly created jar.
-   * @throws IOException
+   * @throws IOException if the jar file cannot be created.
    */
   public static URL createJarWithClasses(final ClassLoader loader, final String... resourceNames)
       throws IOException {
-    final File tmpJar = File.createTempFile(UUID.randomUUID().toString() + "", ".jar");
+    final File tmpJar = File.createTempFile(UUID.randomUUID().toString(), ".jar");
     tmpJar.deleteOnExit();
 
     final Manifest manifest = new Manifest();
-    final JarOutputStream target = new JarOutputStream(new FileOutputStream(tmpJar), manifest);
-    for (final String resourceName : resourceNames) {
-      InputStream is = null;
-      try {
-        is = loader.getResourceAsStream(resourceName);
-        addToJar(resourceName, convertToByteArray(is), target);
-      } finally {
-        if (null != is) {
-          is.close();
+    try (final JarOutputStream target =
+        new JarOutputStream(new FileOutputStream(tmpJar), manifest)) {
+      for (final String resourceName : resourceNames) {
+        try (InputStream is = loader.getResourceAsStream(resourceName)) {
+          if (is != null) {
+            addToJar(resourceName, convertToByteArray(is), target);
+          }
         }
       }
     }
-    target.close();
 
     return tmpJar.toURI().toURL();
   }