Allow transforming classes with missing field types (#8393)

Author: laurit

javaagent-tooling/src/main/java/io/opentelemetry/javaagent/tooling/AgentInstaller.java

@@ -31,7 +31,6 @@
 import io.opentelemetry.javaagent.tooling.asyncannotationsupport.WeakRefAsyncOperationEndStrategies;
 import io.opentelemetry.javaagent.tooling.bootstrap.BootstrapPackagesBuilderImpl;
 import io.opentelemetry.javaagent.tooling.bootstrap.BootstrapPackagesConfigurer;
-import io.opentelemetry.javaagent.tooling.bytebuddy.SafeTypeStrategy;
 import io.opentelemetry.javaagent.tooling.config.AgentConfig;
 import io.opentelemetry.javaagent.tooling.config.ConfigPropertiesBridge;
 import io.opentelemetry.javaagent.tooling.config.EarlyInitAgentConfig;
@@ -59,6 +58,8 @@
 import net.bytebuddy.description.type.TypeDefinition;
 import net.bytebuddy.description.type.TypeDescription;
 import net.bytebuddy.dynamic.DynamicType;
+import net.bytebuddy.dynamic.VisibilityBridgeStrategy;
+import net.bytebuddy.dynamic.scaffold.InstrumentedType;
 import net.bytebuddy.dynamic.scaffold.MethodGraph;
 import net.bytebuddy.utility.JavaModule;
 
@@ -131,11 +132,12 @@ private static void installBytebuddyAgent(
         new AgentBuilder.Default(
                 // default method graph compiler inspects the class hierarchy, we don't need it, so
                 // we use a simpler and faster strategy instead
-                new ByteBuddy().with(MethodGraph.Compiler.ForDeclaredMethods.INSTANCE))
+                new ByteBuddy()
+                    .with(MethodGraph.Compiler.ForDeclaredMethods.INSTANCE)
+                    .with(VisibilityBridgeStrategy.Default.NEVER)
+                    .with(InstrumentedType.Factory.Default.FROZEN))
+            .with(AgentBuilder.TypeStrategy.Default.DECORATE)
             .disableClassFormatChanges()
-            // disableClassFormatChanges sets type strategy to TypeStrategy.Default.REDEFINE_FROZEN
-            // we'll wrap it with our own strategy
-            .with(new SafeTypeStrategy(AgentBuilder.TypeStrategy.Default.REDEFINE_FROZEN))
             .with(AgentBuilder.RedefinitionStrategy.RETRANSFORMATION)
             .with(new RedefinitionDiscoveryStrategy())
             .with(AgentBuilder.DescriptionStrategy.Default.POOL_ONLY)

javaagent-tooling/src/main/java/io/opentelemetry/javaagent/tooling/bytebuddy/SafeTypeStrategy.java

@@ -36,8 +36,8 @@ static void setUp() {
     AgentBuilder builder =
         new AgentBuilder.Default(
                 new ByteBuddy().with(MethodGraph.Compiler.ForDeclaredMethods.INSTANCE))
+            .with(AgentBuilder.TypeStrategy.Default.DECORATE)
             .disableClassFormatChanges()
-            .with(new SafeTypeStrategy(AgentBuilder.TypeStrategy.Default.REDEFINE_FROZEN))
             .with(AgentBuilder.RedefinitionStrategy.RETRANSFORMATION)
             .with(
                 new AgentBuilder.Listener.Adapter() {
@@ -92,8 +92,10 @@ void hasNoErrors() {
   }
 
   // com.google.common.base.Joiner is missing from runtime class path
-  @SuppressWarnings({"UnusedMethod", "MethodCanBeStatic"})
+  @SuppressWarnings({"UnusedMethod", "UnusedVariable", "MethodCanBeStatic"})
   private static class SomeClass {
+    public Joiner joiner;
+
     public static boolean isInstrumented() {
       return false;
     }