Build desktop packages:

[Etoilesforever]

CMake Error at CMakeLists.txt:85 (string_camel_case_to_lower_case_underscore):
Unknown CMake command "string_camel_case_to_lower_case_underscore".

[joshuakimrub]

I experienced the same issue when I used ros2 iron. My solution was to use ros2 humbe instead.

[ChristophSchwanke]

I found this solution:

index adf0512..e55a567 100644
--- a/rcljava/CMakeLists.txt
+++ b/rcljava/CMakeLists.txt
@@ -14,6 +14,7 @@ find_package(rmw REQUIRED)
 find_package(rmw_implementation_cmake REQUIRED)
 
 include(CrossCompilingExtra)
+include(/opt/ros/jazzy/share/rosidl_cmake/cmake/string_camel_case_to_lower_case_underscore.cmake)
 
 if(CMAKE_CROSSCOMPILING)
   find_host_package(Java COMPONENTS Development REQUIRED)