diff --git a/protobuf/protoc-gen-cruxclient/api_generator.cc b/protobuf/protoc-gen-cruxclient/api_generator.cc
index 2b01c5d..0d7055f 100644
--- a/protobuf/protoc-gen-cruxclient/api_generator.cc
+++ b/protobuf/protoc-gen-cruxclient/api_generator.cc
@@ -401,6 +401,7 @@ void APIGenerator::PrintDjinniYAML(
   auto messages = GetMessagesFromFile(file);
   for (const auto message : messages) {
     vars["message_name"] = ClassName(message, false);
+    vars["java_message_name"] = UnderscoresToDollar(vars["message_name"]);
     vars["cpp_type_name"] = DotsToColons(message->full_name());
     vars["objc_header"] = DotsToSlashs(message->full_name());
     vars["file_name"] = StripProto(file->name());
@@ -442,8 +443,8 @@ void APIGenerator::PrintDjinniYAML(
 
     printer->Print("java:\n");
     printer->Indent();
-    printer->Print(vars, "typename: '$java_package$.$message_name$'\n");
-    printer->Print(vars, "boxed: '$java_package$.$message_name$'\n");
+    printer->Print(vars, "typename: '$java_package$.$java_message_name$'\n");
+    printer->Print(vars, "boxed: '$java_package$.$java_message_name$'\n");
     printer->Print("reference: true\n");
     printer->Print("generic: false\n");
     printer->Print("hash: '%s.hashCode()'\n");
@@ -454,7 +455,7 @@ void APIGenerator::PrintDjinniYAML(
     printer->Print(vars, "translator: 'djinni::$cpp_type_name$::Translator'\n");
     printer->Print(vars, "header: '\"$main_file_name$.djinni.jni.h\"'\n");
     printer->Print(vars, "typename: jobject\n");
-    printer->Print(vars, "typeSignature: 'L$java_package_slashes$/$message_name$;'\n");
+    printer->Print(vars, "typeSignature: 'L$java_package_slashes$/$java_message_name$;'\n");
     printer->Outdent();
 
     printer->Print("\n");
@@ -554,7 +555,7 @@ void APIGenerator::PrintDjinniJNISupport(
   vars["dir"] = dir;
   auto messages = GetMessagesFromFile(file);
   for (const auto message : messages) {
-    vars["message_name"] = ClassName(message, false);
+    vars["message_name"] = UnderscoresToDollar(ClassName(message, false));
     vars["cpp_type_name"] = DotsToColons(message->full_name());
     vars["file_name"] = StripProto(file->name());
     vars["cpp_header"] = DotsToSlashs(ToLower(message->full_name()));
diff --git a/protobuf/protoc-gen-cruxclient/common.h b/protobuf/protoc-gen-cruxclient/common.h
index 2ccdbe1..fd1f9b2 100644
--- a/protobuf/protoc-gen-cruxclient/common.h
+++ b/protobuf/protoc-gen-cruxclient/common.h
@@ -133,6 +133,10 @@ inline std::string DotsToSlashs(const std::string &name) {
   return StringReplace(name, ".", "/");
 }
 
+inline std::string UnderscoresToDollar(const std::string &name) {
+  return StringReplace(name, "_", "$");
+}
+
 inline std::string ToLower(const std::string &input) {
   std::string output = input;
   std::transform(output.begin(), output.end(), output.begin(),
diff --git a/protobuf/protoc-gen-cruxclient/generated/routeguide/v1/message.djinni.jni.h b/protobuf/protoc-gen-cruxclient/generated/routeguide/v1/message.djinni.jni.h
index b44973c..99d1cd9 100644
--- a/protobuf/protoc-gen-cruxclient/generated/routeguide/v1/message.djinni.jni.h
+++ b/protobuf/protoc-gen-cruxclient/generated/routeguide/v1/message.djinni.jni.h
@@ -209,10 +209,10 @@ struct Translator {
 #include "routeguide/v1/message.pb.h"
 namespace djinni::routeguide::v1::RouteSummary::Details {
 struct JNIInfo {
-  const GlobalRef<jclass> clazz { jniFindClass("io/grpc/examples/routeguide/RouteSummary_Details")  };
+  const GlobalRef<jclass> clazz { jniFindClass("io/grpc/examples/routeguide/RouteSummary$Details")  };
   const jmethodID method_toBytes { jniGetMethodID(clazz.get(), "toByteArray", "()[B") };
   const jmethodID method_byteSize { jniGetMethodID(clazz.get(), "getSerializedSize", "()I") };
-  const jmethodID method_fromBytes { jniGetStaticMethodID(clazz.get(), "parseFrom", "([B)Lio/grpc/examples/routeguide/RouteSummary_Details;") };
+  const jmethodID method_fromBytes { jniGetStaticMethodID(clazz.get(), "parseFrom", "([B)Lio/grpc/examples/routeguide/RouteSummary$Details;") };
 };
 
 struct Translator {
@@ -250,10 +250,10 @@ struct Translator {
 #include "routeguide/v1/message.pb.h"
 namespace djinni::routeguide::v1::RouteSummary::Details::MoreDetails {
 struct JNIInfo {
-  const GlobalRef<jclass> clazz { jniFindClass("io/grpc/examples/routeguide/RouteSummary_Details_MoreDetails")  };
+  const GlobalRef<jclass> clazz { jniFindClass("io/grpc/examples/routeguide/RouteSummary$Details$MoreDetails")  };
   const jmethodID method_toBytes { jniGetMethodID(clazz.get(), "toByteArray", "()[B") };
   const jmethodID method_byteSize { jniGetMethodID(clazz.get(), "getSerializedSize", "()I") };
-  const jmethodID method_fromBytes { jniGetStaticMethodID(clazz.get(), "parseFrom", "([B)Lio/grpc/examples/routeguide/RouteSummary_Details_MoreDetails;") };
+  const jmethodID method_fromBytes { jniGetStaticMethodID(clazz.get(), "parseFrom", "([B)Lio/grpc/examples/routeguide/RouteSummary$Details$MoreDetails;") };
 };
 
 struct Translator {
@@ -287,4 +287,3 @@ struct Translator {
   }
 };
 }  //namespace djinni::routeguide::v1::RouteSummary::Details::MoreDetails
-
diff --git a/protobuf/protoc-gen-cruxclient/generated/routeguide/v1/message.djinni.yaml b/protobuf/protoc-gen-cruxclient/generated/routeguide/v1/message.djinni.yaml
index 59b0b89..cd87a7c 100644
--- a/protobuf/protoc-gen-cruxclient/generated/routeguide/v1/message.djinni.yaml
+++ b/protobuf/protoc-gen-cruxclient/generated/routeguide/v1/message.djinni.yaml
@@ -168,8 +168,8 @@ objcpp:
   translator: 'djinni::routeguide::v1::RouteSummary::Details::Translator'
   header: '"routeguide/v1/message.djinni.objc.h"'
 java:
-  typename: 'io.grpc.examples.routeguide.RouteSummary_Details'
-  boxed: 'io.grpc.examples.routeguide.RouteSummary_Details'
+  typename: 'io.grpc.examples.routeguide.RouteSummary$Details'
+  boxed: 'io.grpc.examples.routeguide.RouteSummary$Details'
   reference: true
   generic: false
   hash: '%s.hashCode()'
@@ -177,7 +177,7 @@ jni:
   translator: 'djinni::routeguide::v1::RouteSummary::Details::Translator'
   header: '"routeguide/v1/message.djinni.jni.h"'
   typename: jobject
-  typeSignature: 'Lio/grpc/examples/routeguide/RouteSummary_Details;'
+  typeSignature: 'Lio/grpc/examples/routeguide/RouteSummary$Details;'
 
 ---
 name: pb_RouteSummary_Details_MoreDetails
@@ -198,8 +198,8 @@ objcpp:
   translator: 'djinni::routeguide::v1::RouteSummary::Details::MoreDetails::Translator'
   header: '"routeguide/v1/message.djinni.objc.h"'
 java:
-  typename: 'io.grpc.examples.routeguide.RouteSummary_Details_MoreDetails'
-  boxed: 'io.grpc.examples.routeguide.RouteSummary_Details_MoreDetails'
+  typename: 'io.grpc.examples.routeguide.RouteSummary$Details$MoreDetails'
+  boxed: 'io.grpc.examples.routeguide.RouteSummary$Details$MoreDetails'
   reference: true
   generic: false
   hash: '%s.hashCode()'
@@ -207,5 +207,5 @@ jni:
   translator: 'djinni::routeguide::v1::RouteSummary::Details::MoreDetails::Translator'
   header: '"routeguide/v1/message.djinni.jni.h"'
   typename: jobject
-  typeSignature: 'Lio/grpc/examples/routeguide/RouteSummary_Details_MoreDetails;'
+  typeSignature: 'Lio/grpc/examples/routeguide/RouteSummary$Details$MoreDetails;'