From 8f80a42c4d08319294b8d376544a1c64730c8b87 Mon Sep 17 00:00:00 2001
From: Nikolay Martynov <mar.kolya@gmail.com>
Date: Thu, 7 Nov 2019 13:45:56 -0500
Subject: [PATCH] Do not delay tracer on OpenJDK8 with JBOSS

---
 .../main/java/datadog/trace/bootstrap/Agent.java   | 14 +++++++++++++-
 .../java/jvmbootstraptest/LogManagerSetter.java    | 12 +++++++++---
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/Agent.java b/dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/Agent.java
index e3d5fa0690..4b71b5c98f 100644
--- a/dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/Agent.java
+++ b/dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/Agent.java
@@ -70,7 +70,7 @@ public class Agent {
      * events which in turn loads LogManager. This is not a problem on newer JDKs because there JFR uses different
      * logging facility.
      */
-    if (isJavaBefore9() && appUsingCustomLogManager) {
+    if (isJavaBefore9WithJFR() && appUsingCustomLogManager) {
       LOGGER.debug("Custom logger detected. Delaying Datadog Tracer initialization.");
       registerLogManagerCallback(new InstallDatadogTracerCallback(inst, bootstrapURL));
     } else {
@@ -341,4 +341,16 @@ public class Agent {
   private static boolean isJavaBefore9() {
     return System.getProperty("java.version").startsWith("1.");
   }
+
+  private static boolean isJavaBefore9WithJFR() {
+    if (!isJavaBefore9()) {
+      return false;
+    }
+    // FIXME: this is quite a hack because there maybe jfr classes on classpath somehow that have
+    // nothing to do with JDK but this should be safe because only thing this does is to delay
+    // tracer install
+    final String jfrClassResourceName = "jdk.jfr.Recording".replace('.', '/') + ".class";
+    return Thread.currentThread().getContextClassLoader().getResourceAsStream(jfrClassResourceName)
+        != null;
+  }
 }
diff --git a/dd-java-agent/src/test/java/jvmbootstraptest/LogManagerSetter.java b/dd-java-agent/src/test/java/jvmbootstraptest/LogManagerSetter.java
index d13dcef84b..efb7816a4c 100644
--- a/dd-java-agent/src/test/java/jvmbootstraptest/LogManagerSetter.java
+++ b/dd-java-agent/src/test/java/jvmbootstraptest/LogManagerSetter.java
@@ -106,7 +106,7 @@ public class LogManagerSetter {
   }
 
   private static void assertTraceInstallationDelayed(final String message) {
-    if (isJavaBefore9()) {
+    if (isJavaBefore9WithJFR()) {
       customAssert(isTracerInstalled(false), false, message);
     } else {
       customAssert(
@@ -154,7 +154,13 @@ public class LogManagerSetter {
     return false;
   }
 
-  private static boolean isJavaBefore9() {
-    return System.getProperty("java.version").startsWith("1.");
+  private static boolean isJavaBefore9WithJFR() {
+    if (!System.getProperty("java.version").startsWith("1.")) {
+      return false;
+    }
+
+    final String jfrClassResourceName = "jdk.jfr.Recording".replace('.', '/') + ".class";
+    return Thread.currentThread().getContextClassLoader().getResourceAsStream(jfrClassResourceName)
+        != null;
   }
 }