From 86f75b3bb2028e2b14300a2ac84c3996c4bd4f7c Mon Sep 17 00:00:00 2001
From: Tyler Benson <tyler.benson@datadoghq.com>
Date: Wed, 20 May 2020 16:53:02 -0400
Subject: [PATCH] Register WeakMapProvider earlier in AgentInstaller

Specifically it is used statically by `FieldBackedProvider` which was likely called before the `AgentTooling` class was initialized.
---
 .../src/main/java/datadog/trace/bootstrap/WeakMap.java       | 2 +-
 .../java/datadog/trace/agent/tooling/AgentInstaller.java     | 5 +++++
 .../main/java/datadog/trace/agent/tooling/AgentTooling.java  | 2 +-
 3 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/WeakMap.java b/dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/WeakMap.java
index 4486ff4132f..6a16cc4d0ac 100644
--- a/dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/WeakMap.java
+++ b/dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/WeakMap.java
@@ -52,7 +52,7 @@ class Default implements Implementation {
 
       @Override
       public <K, V> WeakMap<K, V> get() {
-        log.warn("WeakMap.Supplier not registered. Returning a synchronized WeakHashMap.");
+        log.debug("WeakMap.Supplier not registered. Returning a synchronized WeakHashMap.");
         return new MapAdapter<>(Collections.synchronizedMap(new WeakHashMap<K, V>()));
       }
     }
diff --git a/dd-java-agent/agent-tooling/src/main/java/datadog/trace/agent/tooling/AgentInstaller.java b/dd-java-agent/agent-tooling/src/main/java/datadog/trace/agent/tooling/AgentInstaller.java
index 03ab1bc6ca3..fdd658a4596 100644
--- a/dd-java-agent/agent-tooling/src/main/java/datadog/trace/agent/tooling/AgentInstaller.java
+++ b/dd-java-agent/agent-tooling/src/main/java/datadog/trace/agent/tooling/AgentInstaller.java
@@ -34,6 +34,11 @@ public static Instrumentation getInstrumentation() {
     return INSTRUMENTATION;
   }
 
+  static {
+    // WeakMap is used by other classes below, so we need to register the provider first.
+    AgentTooling.registerWeakMapProvider();
+  }
+
   public static void installBytebuddyAgent(final Instrumentation inst) {
     if (Config.get().isTraceEnabled()) {
       installBytebuddyAgent(inst, false, new AgentBuilder.Listener[0]);
diff --git a/dd-java-agent/agent-tooling/src/main/java/datadog/trace/agent/tooling/AgentTooling.java b/dd-java-agent/agent-tooling/src/main/java/datadog/trace/agent/tooling/AgentTooling.java
index 1079e2803f2..34a5b420311 100644
--- a/dd-java-agent/agent-tooling/src/main/java/datadog/trace/agent/tooling/AgentTooling.java
+++ b/dd-java-agent/agent-tooling/src/main/java/datadog/trace/agent/tooling/AgentTooling.java
@@ -20,7 +20,7 @@ public class AgentTooling {
     registerWeakMapProvider();
   }
 
-  private static void registerWeakMapProvider() {
+  static void registerWeakMapProvider() {
     if (!WeakMap.Provider.isProviderRegistered()) {
       WeakMap.Provider.registerIfAbsent(new WeakMapSuppliers.WeakConcurrent());
       //    WeakMap.Provider.registerIfAbsent(new WeakMapSuppliers.WeakConcurrent.Inline());